gcc/c-common.c

   1 /* Subroutines shared by all languages that are variants of C.
   2    Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
   3    2001, 2002 Free Software Foundation, Inc.
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify it under
   8 the terms of the GNU General Public License as published by the Free
   9 Software Foundation; either version 2, or (at your option) any later
  10 version.
  11
  12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15 for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING.  If not, write to the Free
  19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
  20 02111-1307, USA.  */
  21
  22 #include "config.h"
  23 #include "system.h"
  24 #include "tree.h"
  25 #include "real.h"
  26 #include "flags.h"
  27 #include "toplev.h"
  28 #include "output.h"
  29 #include "c-pragma.h"
  30 #include "rtl.h"
  31 #include "ggc.h"
  32 #include "expr.h"
  33 #include "c-common.h"
  34 #include "tree-inline.h"
  35 #include "diagnostic.h"
  36 #include "tm_p.h"
  37 #include "obstack.h"
  38 #include "cpplib.h"
  39 #include "target.h"
  40 #include "langhooks.h"
  41 #include "except.h"             /* For USING_SJLJ_EXCEPTIONS.  */
  42
  43 cpp_reader *parse_in;           /* Declared in c-pragma.h.  */
  44
  45 /* We let tm.h override the types used here, to handle trivial differences
  46    such as the choice of unsigned int or long unsigned int for size_t.
  47    When machines start needing nontrivial differences in the size type,
  48    it would be best to do something here to figure out automatically
  49    from other information what type to use.  */
  50
  51 #ifndef SIZE_TYPE
  52 #define SIZE_TYPE "long unsigned int"
  53 #endif
  54
  55 #ifndef WCHAR_TYPE
  56 #define WCHAR_TYPE "int"
  57 #endif
  58
  59 /* WCHAR_TYPE gets overridden by -fshort-wchar.  */
  60 #define MODIFIED_WCHAR_TYPE \
  61         (flag_short_wchar ? "short unsigned int" : WCHAR_TYPE)
  62
  63 #ifndef PTRDIFF_TYPE
  64 #define PTRDIFF_TYPE "long int"
  65 #endif
  66
  67 #ifndef WINT_TYPE
  68 #define WINT_TYPE "unsigned int"
  69 #endif
  70
  71 #ifndef INTMAX_TYPE
  72 #define INTMAX_TYPE ((INT_TYPE_SIZE == LONG_LONG_TYPE_SIZE)     \
  73                      ? "int"                                    \
  74                      : ((LONG_TYPE_SIZE == LONG_LONG_TYPE_SIZE) \
  75                         ? "long int"                            \
  76                         : "long long int"))
  77 #endif
  78
  79 #ifndef UINTMAX_TYPE
  80 #define UINTMAX_TYPE ((INT_TYPE_SIZE == LONG_LONG_TYPE_SIZE)    \
  81                      ? "unsigned int"                           \
  82                      : ((LONG_TYPE_SIZE == LONG_LONG_TYPE_SIZE) \
  83                         ? "long unsigned int"                   \
  84                         : "long long unsigned int"))
  85 #endif
  86
  87 #ifndef STDC_0_IN_SYSTEM_HEADERS
  88 #define STDC_0_IN_SYSTEM_HEADERS 0
  89 #endif
  90
  91 #ifndef REGISTER_PREFIX
  92 #define REGISTER_PREFIX ""
  93 #endif
  94
  95 /* The variant of the C language being processed.  */
  96
  97 enum c_language_kind c_language;
  98
  99 /* The following symbols are subsumed in the c_global_trees array, and
 100    listed here individually for documentation purposes.
 101
 102    INTEGER_TYPE and REAL_TYPE nodes for the standard data types.
 103
 104         tree short_integer_type_node;
 105         tree long_integer_type_node;
 106         tree long_long_integer_type_node;
 107
 108         tree short_unsigned_type_node;
 109         tree long_unsigned_type_node;
 110         tree long_long_unsigned_type_node;
 111
 112         tree boolean_type_node;
 113         tree boolean_false_node;
 114         tree boolean_true_node;
 115
 116         tree ptrdiff_type_node;
 117
 118         tree unsigned_char_type_node;
 119         tree signed_char_type_node;
 120         tree wchar_type_node;
 121         tree signed_wchar_type_node;
 122         tree unsigned_wchar_type_node;
 123
 124         tree float_type_node;
 125         tree double_type_node;
 126         tree long_double_type_node;
 127
 128         tree complex_integer_type_node;
 129         tree complex_float_type_node;
 130         tree complex_double_type_node;
 131         tree complex_long_double_type_node;
 132
 133         tree intQI_type_node;
 134         tree intHI_type_node;
 135         tree intSI_type_node;
 136         tree intDI_type_node;
 137         tree intTI_type_node;
 138
 139         tree unsigned_intQI_type_node;
 140         tree unsigned_intHI_type_node;
 141         tree unsigned_intSI_type_node;
 142         tree unsigned_intDI_type_node;
 143         tree unsigned_intTI_type_node;
 144
 145         tree widest_integer_literal_type_node;
 146         tree widest_unsigned_literal_type_node;
 147
 148    Nodes for types `void *' and `const void *'.
 149
 150         tree ptr_type_node, const_ptr_type_node;
 151
 152    Nodes for types `char *' and `const char *'.
 153
 154         tree string_type_node, const_string_type_node;
 155
 156    Type `char[SOMENUMBER]'.
 157    Used when an array of char is needed and the size is irrelevant.
 158
 159         tree char_array_type_node;
 160
 161    Type `int[SOMENUMBER]' or something like it.
 162    Used when an array of int needed and the size is irrelevant.
 163
 164         tree int_array_type_node;
 165
 166    Type `wchar_t[SOMENUMBER]' or something like it.
 167    Used when a wide string literal is created.
 168
 169         tree wchar_array_type_node;
 170
 171    Type `int ()' -- used for implicit declaration of functions.
 172
 173         tree default_function_type;
 174
 175    A VOID_TYPE node, packaged in a TREE_LIST.
 176
 177         tree void_list_node;
 178
 179   The lazily created VAR_DECLs for __FUNCTION__, __PRETTY_FUNCTION__,
 180   and __func__. (C doesn't generate __FUNCTION__ and__PRETTY_FUNCTION__
 181   VAR_DECLS, but C++ does.)
 182
 183         tree function_name_decl_node;
 184         tree pretty_function_name_decl_node;
 185         tree c99_function_name_decl_node;
 186
 187   Stack of nested function name VAR_DECLs.
 188
 189         tree saved_function_name_decls;
 190
 191 */
 192
 193 tree c_global_trees[CTI_MAX];
 194
 195 /* Nonzero if prepreprocessing only.  */
 196 int flag_preprocess_only;
 197
 198 /* Nonzero if an ISO standard was selected.  It rejects macros in the
 199    user's namespace.  */
 200 int flag_iso;
 201
 202 /* Nonzero if -undef was given.  It suppresses target built-in macros
 203    and assertions.  */
 204 int flag_undef;
 205
 206 /* Nonzero means don't recognize the non-ANSI builtin functions.  */
 207
 208 int flag_no_builtin;
 209
 210 /* Nonzero means don't recognize the non-ANSI builtin functions.
 211    -ansi sets this.  */
 212
 213 int flag_no_nonansi_builtin;
 214
 215 /* Nonzero means give `double' the same size as `float'.  */
 216
 217 int flag_short_double;
 218
 219 /* Nonzero means give `wchar_t' the same size as `short'.  */
 220
 221 int flag_short_wchar;
 222
 223 /* Nonzero means allow Microsoft extensions without warnings or errors.  */
 224 int flag_ms_extensions;
 225
 226 /* Nonzero means warn about use of multicharacter literals.  */
 227
 228 int warn_multichar = 1;
 229
 230 /* Nonzero means warn about possible violations of sequence point rules.  */
 231
 232 int warn_sequence_point;
 233
 234 /* Nonzero means to warn about compile-time division by zero.  */
 235 int warn_div_by_zero = 1;
 236
 237 /* Warn about NULL being passed to argument slots marked as requiring
 238    non-NULL.  */
 239
 240 int warn_nonnull;
 241
 242 /* The elements of `ridpointers' are identifier nodes for the reserved
 243    type names and storage classes.  It is indexed by a RID_... value.  */
 244 tree *ridpointers;
 245
 246 tree (*make_fname_decl)                PARAMS ((tree, int));
 247
 248 /* If non-NULL, the address of a language-specific function that
 249    returns 1 for language-specific statement codes.  */
 250 int (*lang_statement_code_p)           PARAMS ((enum tree_code));
 251
 252 /* If non-NULL, the address of a language-specific function that takes
 253    any action required right before expand_function_end is called.  */
 254 void (*lang_expand_function_end)       PARAMS ((void));
 255
 256 /* Nonzero means the expression being parsed will never be evaluated.
 257    This is a count, since unevaluated expressions can nest.  */
 258 int skip_evaluation;
 259
 260 /* Information about how a function name is generated.  */
 261 struct fname_var_t
 262 {
 263   tree *const decl;     /* pointer to the VAR_DECL.  */
 264   const unsigned rid;   /* RID number for the identifier.  */
 265   const int pretty;     /* How pretty is it? */
 266 };
 267
 268 /* The three ways of getting then name of the current function.  */
 269
 270 const struct fname_var_t fname_vars[] =
 271 {
 272   /* C99 compliant __func__, must be first.  */
 273   {&c99_function_name_decl_node, RID_C99_FUNCTION_NAME, 0},
 274   /* GCC __FUNCTION__ compliant.  */
 275   {&function_name_decl_node, RID_FUNCTION_NAME, 0},
 276   /* GCC __PRETTY_FUNCTION__ compliant.  */
 277   {&pretty_function_name_decl_node, RID_PRETTY_FUNCTION_NAME, 1},
 278   {NULL, 0, 0},
 279 };
 280
 281 static int constant_fits_type_p         PARAMS ((tree, tree));
 282
 283 /* Keep a stack of if statements.  We record the number of compound
 284    statements seen up to the if keyword, as well as the line number
 285    and file of the if.  If a potentially ambiguous else is seen, that
 286    fact is recorded; the warning is issued when we can be sure that
 287    the enclosing if statement does not have an else branch.  */
 288 typedef struct
 289 {
 290   int compstmt_count;
 291   int line;
 292   const char *file;
 293   int needs_warning;
 294   tree if_stmt;
 295 } if_elt;
 296
 297 static if_elt *if_stack;
 298
 299 /* Amount of space in the if statement stack.  */
 300 static int if_stack_space = 0;
 301
 302 /* Stack pointer.  */
 303 static int if_stack_pointer = 0;
 304
 305 static void cb_register_builtins PARAMS ((cpp_reader *));
 306
 307 static tree handle_packed_attribute     PARAMS ((tree *, tree, tree, int,
 308                                                  bool *));
 309 static tree handle_nocommon_attribute   PARAMS ((tree *, tree, tree, int,
 310                                                  bool *));
 311 static tree handle_common_attribute     PARAMS ((tree *, tree, tree, int,
 312                                                  bool *));
 313 static tree handle_noreturn_attribute   PARAMS ((tree *, tree, tree, int,
 314                                                  bool *));
 315 static tree handle_noinline_attribute   PARAMS ((tree *, tree, tree, int,
 316                                                  bool *));
 317 static tree handle_always_inline_attribute PARAMS ((tree *, tree, tree, int,
 318                                                     bool *));
 319 static tree handle_used_attribute       PARAMS ((tree *, tree, tree, int,
 320                                                  bool *));
 321 static tree handle_unused_attribute     PARAMS ((tree *, tree, tree, int,
 322                                                  bool *));
 323 static tree handle_const_attribute      PARAMS ((tree *, tree, tree, int,
 324                                                  bool *));
 325 static tree handle_transparent_union_attribute PARAMS ((tree *, tree, tree,
 326                                                         int, bool *));
 327 static tree handle_constructor_attribute PARAMS ((tree *, tree, tree, int,
 328                                                   bool *));
 329 static tree handle_destructor_attribute PARAMS ((tree *, tree, tree, int,
 330                                                  bool *));
 331 static tree handle_mode_attribute       PARAMS ((tree *, tree, tree, int,
 332                                                  bool *));
 333 static tree handle_section_attribute    PARAMS ((tree *, tree, tree, int,
 334                                                  bool *));
 335 static tree handle_aligned_attribute    PARAMS ((tree *, tree, tree, int,
 336                                                  bool *));
 337 static tree handle_weak_attribute       PARAMS ((tree *, tree, tree, int,
 338                                                  bool *));
 339 static tree handle_alias_attribute      PARAMS ((tree *, tree, tree, int,
 340                                                  bool *));
 341 static tree handle_visibility_attribute PARAMS ((tree *, tree, tree, int,
 342                                                  bool *));
 343 static tree handle_no_instrument_function_attribute PARAMS ((tree *, tree,
 344                                                              tree, int,
 345                                                              bool *));
 346 static tree handle_malloc_attribute     PARAMS ((tree *, tree, tree, int,
 347                                                  bool *));
 348 static tree handle_no_limit_stack_attribute PARAMS ((tree *, tree, tree, int,
 349                                                      bool *));
 350 static tree handle_pure_attribute       PARAMS ((tree *, tree, tree, int,
 351                                                  bool *));
 352 static tree handle_deprecated_attribute PARAMS ((tree *, tree, tree, int,
 353                                                  bool *));
 354 static tree handle_vector_size_attribute PARAMS ((tree *, tree, tree, int,
 355                                                   bool *));
 356 static tree handle_nonnull_attribute    PARAMS ((tree *, tree, tree, int,
 357                                                  bool *));
 358 static tree handle_nothrow_attribute    PARAMS ((tree *, tree, tree, int,
 359                                                  bool *));
 360 static tree vector_size_helper PARAMS ((tree, tree));
 361
 362 static void check_function_nonnull      PARAMS ((tree, tree));
 363 static void check_nonnull_arg           PARAMS ((void *, tree,
 364                                                  unsigned HOST_WIDE_INT));
 365 static bool nonnull_check_p             PARAMS ((tree, unsigned HOST_WIDE_INT));
 366 static bool get_nonnull_operand         PARAMS ((tree,
 367                                                  unsigned HOST_WIDE_INT *));
 368 void builtin_define_std PARAMS ((const char *));
 369 static void builtin_define_with_value PARAMS ((const char *, const char *,
 370                                                int));
 371 static void builtin_define_type_max PARAMS ((const char *, tree, int));
 372
 373 /* Table of machine-independent attributes common to all C-like languages.  */
 374 const struct attribute_spec c_common_attribute_table[] =
 375 {
 376   /* { name, min_len, max_len, decl_req, type_req, fn_type_req, handler } */
 377   { "packed",                 0, 0, false, false, false,
 378                               handle_packed_attribute },
 379   { "nocommon",               0, 0, true,  false, false,
 380                               handle_nocommon_attribute },
 381   { "common",                 0, 0, true,  false, false,
 382                               handle_common_attribute },
 383   /* FIXME: logically, noreturn attributes should be listed as
 384      "false, true, true" and apply to function types.  But implementing this
 385      would require all the places in the compiler that use TREE_THIS_VOLATILE
 386      on a decl to identify non-returning functions to be located and fixed
 387      to check the function type instead.  */
 388   { "noreturn",               0, 0, true,  false, false,
 389                               handle_noreturn_attribute },
 390   { "volatile",               0, 0, true,  false, false,
 391                               handle_noreturn_attribute },
 392   { "noinline",               0, 0, true,  false, false,
 393                               handle_noinline_attribute },
 394   { "always_inline",          0, 0, true,  false, false,
 395                               handle_always_inline_attribute },
 396   { "used",                   0, 0, true,  false, false,
 397                               handle_used_attribute },
 398   { "unused",                 0, 0, false, false, false,
 399                               handle_unused_attribute },
 400   /* The same comments as for noreturn attributes apply to const ones.  */
 401   { "const",                  0, 0, true,  false, false,
 402                               handle_const_attribute },
 403   { "transparent_union",      0, 0, false, false, false,
 404                               handle_transparent_union_attribute },
 405   { "constructor",            0, 0, true,  false, false,
 406                               handle_constructor_attribute },
 407   { "destructor",             0, 0, true,  false, false,
 408                               handle_destructor_attribute },
 409   { "mode",                   1, 1, false,  true, false,
 410                               handle_mode_attribute },
 411   { "section",                1, 1, true,  false, false,
 412                               handle_section_attribute },
 413   { "aligned",                0, 1, false, false, false,
 414                               handle_aligned_attribute },
 415   { "weak",                   0, 0, true,  false, false,
 416                               handle_weak_attribute },
 417   { "alias",                  1, 1, true,  false, false,
 418                               handle_alias_attribute },
 419   { "no_instrument_function", 0, 0, true,  false, false,
 420                               handle_no_instrument_function_attribute },
 421   { "malloc",                 0, 0, true,  false, false,
 422                               handle_malloc_attribute },
 423   { "no_stack_limit",         0, 0, true,  false, false,
 424                               handle_no_limit_stack_attribute },
 425   { "pure",                   0, 0, true,  false, false,
 426                               handle_pure_attribute },
 427   { "deprecated",             0, 0, false, false, false,
 428                               handle_deprecated_attribute },
 429   { "vector_size",            1, 1, false, true, false,
 430                               handle_vector_size_attribute },
 431   { "visibility",             1, 1, true,  false, false,
 432                               handle_visibility_attribute },
 433   { "nonnull",                0, -1, false, true, true,
 434                               handle_nonnull_attribute },
 435   { "nothrow",                0, 0, true,  false, false,
 436                               handle_nothrow_attribute },
 437   { "may_alias",              0, 0, false, true, false, NULL },
 438   { NULL,                     0, 0, false, false, false, NULL }
 439 };
 440
 441 /* Give the specifications for the format attributes, used by C and all
 442    descendents.  */
 443
 444 const struct attribute_spec c_common_format_attribute_table[] =
 445 {
 446   /* { name, min_len, max_len, decl_req, type_req, fn_type_req, handler } */
 447   { "format",                 3, 3, false, true,  true,
 448                               handle_format_attribute },
 449   { "format_arg",             1, 1, false, true,  true,
 450                               handle_format_arg_attribute },
 451   { NULL,                     0, 0, false, false, false, NULL }
 452 };
 453
 454 /* Record the start of an if-then, and record the start of it
 455    for ambiguous else detection.
 456
 457    COND is the condition for the if-then statement.
 458
 459    IF_STMT is the statement node that has already been created for
 460    this if-then statement.  It is created before parsing the
 461    condition to keep line number information accurate.  */
 462
 463 void
 464 c_expand_start_cond (cond, compstmt_count, if_stmt)
 465      tree cond;
 466      int compstmt_count;
 467      tree if_stmt;
 468 {
 469   /* Make sure there is enough space on the stack.  */
 470   if (if_stack_space == 0)
 471     {
 472       if_stack_space = 10;
 473       if_stack = (if_elt *) xmalloc (10 * sizeof (if_elt));
 474     }
 475   else if (if_stack_space == if_stack_pointer)
 476     {
 477       if_stack_space += 10;
 478       if_stack = (if_elt *) xrealloc (if_stack, if_stack_space * sizeof (if_elt));
 479     }
 480
 481   IF_COND (if_stmt) = cond;
 482   add_stmt (if_stmt);
 483
 484   /* Record this if statement.  */
 485   if_stack[if_stack_pointer].compstmt_count = compstmt_count;
 486   if_stack[if_stack_pointer].file = input_filename;
 487   if_stack[if_stack_pointer].line = lineno;
 488   if_stack[if_stack_pointer].needs_warning = 0;
 489   if_stack[if_stack_pointer].if_stmt = if_stmt;
 490   if_stack_pointer++;
 491 }
 492
 493 /* Called after the then-clause for an if-statement is processed.  */
 494
 495 void
 496 c_finish_then ()
 497 {
 498   tree if_stmt = if_stack[if_stack_pointer - 1].if_stmt;
 499   RECHAIN_STMTS (if_stmt, THEN_CLAUSE (if_stmt));
 500 }
 501
 502 /* Record the end of an if-then.  Optionally warn if a nested
 503    if statement had an ambiguous else clause.  */
 504
 505 void
 506 c_expand_end_cond ()
 507 {
 508   if_stack_pointer--;
 509   if (if_stack[if_stack_pointer].needs_warning)
 510     warning_with_file_and_line (if_stack[if_stack_pointer].file,
 511                                 if_stack[if_stack_pointer].line,
 512                                 "suggest explicit braces to avoid ambiguous `else'");
 513   last_expr_type = NULL_TREE;
 514 }
 515
 516 /* Called between the then-clause and the else-clause
 517    of an if-then-else.  */
 518
 519 void
 520 c_expand_start_else ()
 521 {
 522   /* An ambiguous else warning must be generated for the enclosing if
 523      statement, unless we see an else branch for that one, too.  */
 524   if (warn_parentheses
 525       && if_stack_pointer > 1
 526       && (if_stack[if_stack_pointer - 1].compstmt_count
 527           == if_stack[if_stack_pointer - 2].compstmt_count))
 528     if_stack[if_stack_pointer - 2].needs_warning = 1;
 529
 530   /* Even if a nested if statement had an else branch, it can't be
 531      ambiguous if this one also has an else.  So don't warn in that
 532      case.  Also don't warn for any if statements nested in this else.  */
 533   if_stack[if_stack_pointer - 1].needs_warning = 0;
 534   if_stack[if_stack_pointer - 1].compstmt_count--;
 535 }
 536
 537 /* Called after the else-clause for an if-statement is processed.  */
 538
 539 void
 540 c_finish_else ()
 541 {
 542   tree if_stmt = if_stack[if_stack_pointer - 1].if_stmt;
 543   RECHAIN_STMTS (if_stmt, ELSE_CLAUSE (if_stmt));
 544 }
 545
 546 /* Begin an if-statement.  Returns a newly created IF_STMT if
 547    appropriate.
 548
 549    Unlike the C++ front-end, we do not call add_stmt here; it is
 550    probably safe to do so, but I am not very familiar with this
 551    code so I am being extra careful not to change its behavior
 552    beyond what is strictly necessary for correctness.  */
 553
 554 tree
 555 c_begin_if_stmt ()
 556 {
 557   tree r;
 558   r = build_stmt (IF_STMT, NULL_TREE, NULL_TREE, NULL_TREE);
 559   return r;
 560 }
 561
 562 /* Begin a while statement.  Returns a newly created WHILE_STMT if
 563    appropriate.
 564
 565    Unlike the C++ front-end, we do not call add_stmt here; it is
 566    probably safe to do so, but I am not very familiar with this
 567    code so I am being extra careful not to change its behavior
 568    beyond what is strictly necessary for correctness.  */
 569
 570 tree
 571 c_begin_while_stmt ()
 572 {
 573   tree r;
 574   r = build_stmt (WHILE_STMT, NULL_TREE, NULL_TREE);
 575   return r;
 576 }
 577
 578 void
 579 c_finish_while_stmt_cond (cond, while_stmt)
 580      tree while_stmt;
 581      tree cond;
 582 {
 583   WHILE_COND (while_stmt) = cond;
 584 }
 585
 586 /* Push current bindings for the function name VAR_DECLS.  */
 587
 588 void
 589 start_fname_decls ()
 590 {
 591   unsigned ix;
 592   tree saved = NULL_TREE;
 593
 594   for (ix = 0; fname_vars[ix].decl; ix++)
 595     {
 596       tree decl = *fname_vars[ix].decl;
 597
 598       if (decl)
 599         {
 600           saved = tree_cons (decl, build_int_2 (ix, 0), saved);
 601           *fname_vars[ix].decl = NULL_TREE;
 602         }
 603     }
 604   if (saved || saved_function_name_decls)
 605     /* Normally they'll have been NULL, so only push if we've got a
 606        stack, or they are non-NULL.  */
 607     saved_function_name_decls = tree_cons (saved, NULL_TREE,
 608                                            saved_function_name_decls);
 609 }
 610
 611 /* Finish up the current bindings, adding them into the
 612    current function's statement tree. This is done by wrapping the
 613    function's body in a COMPOUND_STMT containing these decls too. This
 614    must be done _before_ finish_stmt_tree is called. If there is no
 615    current function, we must be at file scope and no statements are
 616    involved. Pop the previous bindings.  */
 617
 618 void
 619 finish_fname_decls ()
 620 {
 621   unsigned ix;
 622   tree body = NULL_TREE;
 623   tree stack = saved_function_name_decls;
 624
 625   for (; stack && TREE_VALUE (stack); stack = TREE_CHAIN (stack))
 626     body = chainon (TREE_VALUE (stack), body);
 627
 628   if (body)
 629     {
 630       /* They were called into existence, so add to statement tree.  */
 631       body = chainon (body,
 632                       TREE_CHAIN (DECL_SAVED_TREE (current_function_decl)));
 633       body = build_stmt (COMPOUND_STMT, body);
 634
 635       COMPOUND_STMT_NO_SCOPE (body) = 1;
 636       TREE_CHAIN (DECL_SAVED_TREE (current_function_decl)) = body;
 637     }
 638
 639   for (ix = 0; fname_vars[ix].decl; ix++)
 640     *fname_vars[ix].decl = NULL_TREE;
 641
 642   if (stack)
 643     {
 644       /* We had saved values, restore them.  */
 645       tree saved;
 646
 647       for (saved = TREE_PURPOSE (stack); saved; saved = TREE_CHAIN (saved))
 648         {
 649           tree decl = TREE_PURPOSE (saved);
 650           unsigned ix = TREE_INT_CST_LOW (TREE_VALUE (saved));
 651
 652           *fname_vars[ix].decl = decl;
 653         }
 654       stack = TREE_CHAIN (stack);
 655     }
 656   saved_function_name_decls = stack;
 657 }
 658
 659 /* Return the text name of the current function, suitable prettified
 660    by PRETTY_P.  */
 661
 662 const char *
 663 fname_as_string (pretty_p)
 664      int pretty_p;
 665 {
 666   const char *name = NULL;
 667
 668   if (pretty_p)
 669     name = (current_function_decl
 670             ? (*lang_hooks.decl_printable_name) (current_function_decl, 2)
 671             : "top level");
 672   else if (current_function_decl && DECL_NAME (current_function_decl))
 673     name = IDENTIFIER_POINTER (DECL_NAME (current_function_decl));
 674   else
 675     name = "";
 676   return name;
 677 }
 678
 679 /* Return the text name of the current function, formatted as
 680    required by the supplied RID value.  */
 681
 682 const char *
 683 fname_string (rid)
 684      unsigned rid;
 685 {
 686   unsigned ix;
 687
 688   for (ix = 0; fname_vars[ix].decl; ix++)
 689     if (fname_vars[ix].rid == rid)
 690       break;
 691   return fname_as_string (fname_vars[ix].pretty);
 692 }
 693
 694 /* Return the VAR_DECL for a const char array naming the current
 695    function. If the VAR_DECL has not yet been created, create it
 696    now. RID indicates how it should be formatted and IDENTIFIER_NODE
 697    ID is its name (unfortunately C and C++ hold the RID values of
 698    keywords in different places, so we can't derive RID from ID in
 699    this language independent code.  */
 700
 701 tree
 702 fname_decl (rid, id)
 703      unsigned rid;
 704      tree id;
 705 {
 706   unsigned ix;
 707   tree decl = NULL_TREE;
 708
 709   for (ix = 0; fname_vars[ix].decl; ix++)
 710     if (fname_vars[ix].rid == rid)
 711       break;
 712
 713   decl = *fname_vars[ix].decl;
 714   if (!decl)
 715     {
 716       tree saved_last_tree = last_tree;
 717
 718       decl = (*make_fname_decl) (id, fname_vars[ix].pretty);
 719       if (last_tree != saved_last_tree)
 720         {
 721           /* We created some statement tree for the decl. This belongs
 722              at the start of the function, so remove it now and reinsert
 723              it after the function is complete.  */
 724           tree stmts = TREE_CHAIN (saved_last_tree);
 725
 726           TREE_CHAIN (saved_last_tree) = NULL_TREE;
 727           last_tree = saved_last_tree;
 728           saved_function_name_decls = tree_cons (decl, stmts,
 729                                                  saved_function_name_decls);
 730         }
 731       *fname_vars[ix].decl = decl;
 732     }
 733   if (!ix && !current_function_decl)
 734     pedwarn_with_decl (decl, "`%s' is not defined outside of function scope");
 735
 736   return decl;
 737 }
 738
 739 /* Given a STRING_CST, give it a suitable array-of-chars data type.  */
 740
 741 tree
 742 fix_string_type (value)
 743       tree value;
 744 {
 745   const int wchar_bytes = TYPE_PRECISION (wchar_type_node) / BITS_PER_UNIT;
 746   const int wide_flag = TREE_TYPE (value) == wchar_array_type_node;
 747   const int nchars_max = flag_isoc99 ? 4095 : 509;
 748   int length = TREE_STRING_LENGTH (value);
 749   int nchars;
 750
 751   /* Compute the number of elements, for the array type.  */
 752   nchars = wide_flag ? length / wchar_bytes : length;
 753
 754   if (pedantic && nchars - 1 > nchars_max && c_language == clk_c)
 755     pedwarn ("string length `%d' is greater than the length `%d' ISO C%d compilers are required to support",
 756              nchars - 1, nchars_max, flag_isoc99 ? 99 : 89);
 757
 758   /* Create the array type for the string constant.
 759      -Wwrite-strings says make the string constant an array of const char
 760      so that copying it to a non-const pointer will get a warning.
 761      For C++, this is the standard behavior.  */
 762   if (flag_const_strings && ! flag_writable_strings)
 763     {
 764       tree elements
 765         = build_type_variant (wide_flag ? wchar_type_node : char_type_node,
 766                               1, 0);
 767       TREE_TYPE (value)
 768         = build_array_type (elements,
 769                             build_index_type (build_int_2 (nchars - 1, 0)));
 770     }
 771   else
 772     TREE_TYPE (value)
 773       = build_array_type (wide_flag ? wchar_type_node : char_type_node,
 774                           build_index_type (build_int_2 (nchars - 1, 0)));
 775
 776   TREE_CONSTANT (value) = 1;
 777   TREE_READONLY (value) = ! flag_writable_strings;
 778   TREE_STATIC (value) = 1;
 779   return value;
 780 }
 781
 782 /* Given a VARRAY of STRING_CST nodes, concatenate them into one
 783    STRING_CST.  */
 784
 785 tree
 786 combine_strings (strings)
 787      varray_type strings;
 788 {
 789   const int wchar_bytes = TYPE_PRECISION (wchar_type_node) / BITS_PER_UNIT;
 790   const int nstrings = VARRAY_ACTIVE_SIZE (strings);
 791   tree value, t;
 792   int length = 1;
 793   int wide_length = 0;
 794   int wide_flag = 0;
 795   int i;
 796   char *p, *q;
 797
 798   /* Don't include the \0 at the end of each substring.  Count wide
 799      strings and ordinary strings separately.  */
 800   for (i = 0; i < nstrings; ++i)
 801     {
 802       t = VARRAY_TREE (strings, i);
 803
 804       if (TREE_TYPE (t) == wchar_array_type_node)
 805         {
 806           wide_length += TREE_STRING_LENGTH (t) - wchar_bytes;
 807           wide_flag = 1;
 808         }
 809       else
 810         {
 811           length += (TREE_STRING_LENGTH (t) - 1);
 812           if (C_ARTIFICIAL_STRING_P (t) && !in_system_header)
 813             warning ("concatenation of string literals with __FUNCTION__ is deprecated");
 814         }
 815     }
 816
 817   /* If anything is wide, the non-wides will be converted,
 818      which makes them take more space.  */
 819   if (wide_flag)
 820     length = length * wchar_bytes + wide_length;
 821
 822   p = xmalloc (length);
 823
 824   /* Copy the individual strings into the new combined string.
 825      If the combined string is wide, convert the chars to ints
 826      for any individual strings that are not wide.  */
 827
 828   q = p;
 829   for (i = 0; i < nstrings; ++i)
 830     {
 831       int len, this_wide;
 832
 833       t = VARRAY_TREE (strings, i);
 834       this_wide = TREE_TYPE (t) == wchar_array_type_node;
 835       len = TREE_STRING_LENGTH (t) - (this_wide ? wchar_bytes : 1);
 836       if (this_wide == wide_flag)
 837         {
 838           memcpy (q, TREE_STRING_POINTER (t), len);
 839           q += len;
 840         }
 841       else
 842         {
 843           const int nzeros = (TYPE_PRECISION (wchar_type_node)
 844                               / BITS_PER_UNIT) - 1;
 845           int j, k;
 846
 847           if (BYTES_BIG_ENDIAN)
 848             {
 849               for (k = 0; k < len; k++)
 850                 {
 851                   for (j = 0; j < nzeros; j++)
 852                     *q++ = 0;
 853                   *q++ = TREE_STRING_POINTER (t)[k];
 854                 }
 855             }
 856           else
 857             {
 858               for (k = 0; k < len; k++)
 859                 {
 860                   *q++ = TREE_STRING_POINTER (t)[k];
 861                   for (j = 0; j < nzeros; j++)
 862                     *q++ = 0;
 863                 }
 864             }
 865         }
 866     }
 867
 868   /* Nul terminate the string.  */
 869   if (wide_flag)
 870     {
 871       for (i = 0; i < wchar_bytes; i++)
 872         *q++ = 0;
 873     }
 874   else
 875     *q = 0;
 876
 877   value = build_string (length, p);
 878   free (p);
 879
 880   if (wide_flag)
 881     TREE_TYPE (value) = wchar_array_type_node;
 882   else
 883     TREE_TYPE (value) = char_array_type_node;
 884
 885   return value;
 886 }
 887 \f
 888 static int is_valid_printf_arglist PARAMS ((tree));
 889 static rtx c_expand_builtin PARAMS ((tree, rtx, enum machine_mode, enum expand_modifier));
 890 static rtx c_expand_builtin_printf PARAMS ((tree, rtx, enum machine_mode,
 891                                             enum expand_modifier, int, int));
 892 static rtx c_expand_builtin_fprintf PARAMS ((tree, rtx, enum machine_mode,
 893                                              enum expand_modifier, int, int));
 894 \f
 895 /* Print a warning if a constant expression had overflow in folding.
 896    Invoke this function on every expression that the language
 897    requires to be a constant expression.
 898    Note the ANSI C standard says it is erroneous for a
 899    constant expression to overflow.  */
 900
 901 void
 902 constant_expression_warning (value)
 903      tree value;
 904 {
 905   if ((TREE_CODE (value) == INTEGER_CST || TREE_CODE (value) == REAL_CST
 906        || TREE_CODE (value) == VECTOR_CST
 907        || TREE_CODE (value) == COMPLEX_CST)
 908       && TREE_CONSTANT_OVERFLOW (value) && pedantic)
 909     pedwarn ("overflow in constant expression");
 910 }
 911
 912 /* Print a warning if an expression had overflow in folding.
 913    Invoke this function on every expression that
 914    (1) appears in the source code, and
 915    (2) might be a constant expression that overflowed, and
 916    (3) is not already checked by convert_and_check;
 917    however, do not invoke this function on operands of explicit casts.  */
 918
 919 void
 920 overflow_warning (value)
 921      tree value;
 922 {
 923   if ((TREE_CODE (value) == INTEGER_CST
 924        || (TREE_CODE (value) == COMPLEX_CST
 925            && TREE_CODE (TREE_REALPART (value)) == INTEGER_CST))
 926       && TREE_OVERFLOW (value))
 927     {
 928       TREE_OVERFLOW (value) = 0;
 929       if (skip_evaluation == 0)
 930         warning ("integer overflow in expression");
 931     }
 932   else if ((TREE_CODE (value) == REAL_CST
 933             || (TREE_CODE (value) == COMPLEX_CST
 934                 && TREE_CODE (TREE_REALPART (value)) == REAL_CST))
 935            && TREE_OVERFLOW (value))
 936     {
 937       TREE_OVERFLOW (value) = 0;
 938       if (skip_evaluation == 0)
 939         warning ("floating point overflow in expression");
 940     }
 941   else if (TREE_CODE (value) == VECTOR_CST && TREE_OVERFLOW (value))
 942     {
 943       TREE_OVERFLOW (value) = 0;
 944       if (skip_evaluation == 0)
 945         warning ("vector overflow in expression");
 946     }
 947 }
 948
 949 /* Print a warning if a large constant is truncated to unsigned,
 950    or if -Wconversion is used and a constant < 0 is converted to unsigned.
 951    Invoke this function on every expression that might be implicitly
 952    converted to an unsigned type.  */
 953
 954 void
 955 unsigned_conversion_warning (result, operand)
 956      tree result, operand;
 957 {
 958   tree type = TREE_TYPE (result);
 959
 960   if (TREE_CODE (operand) == INTEGER_CST
 961       && TREE_CODE (type) == INTEGER_TYPE
 962       && TREE_UNSIGNED (type)
 963       && skip_evaluation == 0
 964       && !int_fits_type_p (operand, type))
 965     {
 966       if (!int_fits_type_p (operand, c_common_signed_type (type)))
 967         /* This detects cases like converting -129 or 256 to unsigned char.  */
 968         warning ("large integer implicitly truncated to unsigned type");
 969       else if (warn_conversion)
 970         warning ("negative integer implicitly converted to unsigned type");
 971     }
 972 }
 973
 974 /* Nonzero if constant C has a value that is permissible
 975    for type TYPE (an INTEGER_TYPE).  */
 976
 977 static int
 978 constant_fits_type_p (c, type)
 979      tree c, type;
 980 {
 981   if (TREE_CODE (c) == INTEGER_CST)
 982     return int_fits_type_p (c, type);
 983
 984   c = convert (type, c);
 985   return !TREE_OVERFLOW (c);
 986 }
 987
 988 /* Convert EXPR to TYPE, warning about conversion problems with constants.
 989    Invoke this function on every expression that is converted implicitly,
 990    i.e. because of language rules and not because of an explicit cast.  */
 991
 992 tree
 993 convert_and_check (type, expr)
 994      tree type, expr;
 995 {
 996   tree t = convert (type, expr);
 997   if (TREE_CODE (t) == INTEGER_CST)
 998     {
 999       if (TREE_OVERFLOW (t))
1000         {
1001           TREE_OVERFLOW (t) = 0;
1002
1003           /* Do not diagnose overflow in a constant expression merely
1004              because a conversion overflowed.  */
1005           TREE_CONSTANT_OVERFLOW (t) = TREE_CONSTANT_OVERFLOW (expr);
1006
1007           /* No warning for converting 0x80000000 to int.  */
1008           if (!(TREE_UNSIGNED (type) < TREE_UNSIGNED (TREE_TYPE (expr))
1009                 && TREE_CODE (TREE_TYPE (expr)) == INTEGER_TYPE
1010                 && TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (expr))))
1011             /* If EXPR fits in the unsigned version of TYPE,
1012                don't warn unless pedantic.  */
1013             if ((pedantic
1014                  || TREE_UNSIGNED (type)
1015                  || ! constant_fits_type_p (expr,
1016                                             c_common_unsigned_type (type)))
1017                 && skip_evaluation == 0)
1018               warning ("overflow in implicit constant conversion");
1019         }
1020       else
1021         unsigned_conversion_warning (t, expr);
1022     }
1023   return t;
1024 }
1025 \f
1026 /* A node in a list that describes references to variables (EXPR), which are
1027    either read accesses if WRITER is zero, or write accesses, in which case
1028    WRITER is the parent of EXPR.  */
1029 struct tlist
1030 {
1031   struct tlist *next;
1032   tree expr, writer;
1033 };
1034
1035 /* Used to implement a cache the results of a call to verify_tree.  We only
1036    use this for SAVE_EXPRs.  */
1037 struct tlist_cache
1038 {
1039   struct tlist_cache *next;
1040   struct tlist *cache_before_sp;
1041   struct tlist *cache_after_sp;
1042   tree expr;
1043 };
1044
1045 /* Obstack to use when allocating tlist structures, and corresponding
1046    firstobj.  */
1047 static struct obstack tlist_obstack;
1048 static char *tlist_firstobj = 0;
1049
1050 /* Keep track of the identifiers we've warned about, so we can avoid duplicate
1051    warnings.  */
1052 static struct tlist *warned_ids;
1053 /* SAVE_EXPRs need special treatment.  We process them only once and then
1054    cache the results.  */
1055 static struct tlist_cache *save_expr_cache;
1056
1057 static void add_tlist PARAMS ((struct tlist **, struct tlist *, tree, int));
1058 static void merge_tlist PARAMS ((struct tlist **, struct tlist *, int));
1059 static void verify_tree PARAMS ((tree, struct tlist **, struct tlist **, tree));
1060 static int warning_candidate_p PARAMS ((tree));
1061 static void warn_for_collisions PARAMS ((struct tlist *));
1062 static void warn_for_collisions_1 PARAMS ((tree, tree, struct tlist *, int));
1063 static struct tlist *new_tlist PARAMS ((struct tlist *, tree, tree));
1064 static void verify_sequence_points PARAMS ((tree));
1065
1066 /* Create a new struct tlist and fill in its fields.  */
1067 static struct tlist *
1068 new_tlist (next, t, writer)
1069      struct tlist *next;
1070      tree t;
1071      tree writer;
1072 {
1073   struct tlist *l;
1074   l = (struct tlist *) obstack_alloc (&tlist_obstack, sizeof *l);
1075   l->next = next;
1076   l->expr = t;
1077   l->writer = writer;
1078   return l;
1079 }
1080
1081 /* Add duplicates of the nodes found in ADD to the list *TO.  If EXCLUDE_WRITER
1082    is nonnull, we ignore any node we find which has a writer equal to it.  */
1083
1084 static void
1085 add_tlist (to, add, exclude_writer, copy)
1086      struct tlist **to;
1087      struct tlist *add;
1088      tree exclude_writer;
1089      int copy;
1090 {
1091   while (add)
1092     {
1093       struct tlist *next = add->next;
1094       if (! copy)
1095         add->next = *to;
1096       if (! exclude_writer || add->writer != exclude_writer)
1097         *to = copy ? new_tlist (*to, add->expr, add->writer) : add;
1098       add = next;
1099     }
1100 }
1101
1102 /* Merge the nodes of ADD into TO.  This merging process is done so that for
1103    each variable that already exists in TO, no new node is added; however if
1104    there is a write access recorded in ADD, and an occurrence on TO is only
1105    a read access, then the occurrence in TO will be modified to record the
1106    write.  */
1107
1108 static void
1109 merge_tlist (to, add, copy)
1110      struct tlist **to;
1111      struct tlist *add;
1112      int copy;
1113 {
1114   struct tlist **end = to;
1115
1116   while (*end)
1117     end = &(*end)->next;
1118
1119   while (add)
1120     {
1121       int found = 0;
1122       struct tlist *tmp2;
1123       struct tlist *next = add->next;
1124
1125       for (tmp2 = *to; tmp2; tmp2 = tmp2->next)
1126         if (tmp2->expr == add->expr)
1127           {
1128             found = 1;
1129             if (! tmp2->writer)
1130               tmp2->writer = add->writer;
1131           }
1132       if (! found)
1133         {
1134           *end = copy ? add : new_tlist (NULL, add->expr, add->writer);
1135           end = &(*end)->next;
1136           *end = 0;
1137         }
1138       add = next;
1139     }
1140 }
1141
1142 /* WRITTEN is a variable, WRITER is its parent.  Warn if any of the variable
1143    references in list LIST conflict with it, excluding reads if ONLY writers
1144    is nonzero.  */
1145
1146 static void
1147 warn_for_collisions_1 (written, writer, list, only_writes)
1148      tree written, writer;
1149      struct tlist *list;
1150      int only_writes;
1151 {
1152   struct tlist *tmp;
1153
1154   /* Avoid duplicate warnings.  */
1155   for (tmp = warned_ids; tmp; tmp = tmp->next)
1156     if (tmp->expr == written)
1157       return;
1158
1159   while (list)
1160     {
1161       if (list->expr == written
1162           && list->writer != writer
1163           && (! only_writes || list->writer))
1164         {
1165           warned_ids = new_tlist (warned_ids, written, NULL_TREE);
1166           warning ("operation on `%s' may be undefined",
1167                    IDENTIFIER_POINTER (DECL_NAME (list->expr)));
1168         }
1169       list = list->next;
1170     }
1171 }
1172
1173 /* Given a list LIST of references to variables, find whether any of these
1174    can cause conflicts due to missing sequence points.  */
1175
1176 static void
1177 warn_for_collisions (list)
1178      struct tlist *list;
1179 {
1180   struct tlist *tmp;
1181
1182   for (tmp = list; tmp; tmp = tmp->next)
1183     {
1184       if (tmp->writer)
1185         warn_for_collisions_1 (tmp->expr, tmp->writer, list, 0);
1186     }
1187 }
1188
1189 /* Return nonzero if X is a tree that can be verified by the sequence point
1190    warnings.  */
1191 static int
1192 warning_candidate_p (x)
1193      tree x;
1194 {
1195   return TREE_CODE (x) == VAR_DECL || TREE_CODE (x) == PARM_DECL;
1196 }
1197
1198 /* Walk the tree X, and record accesses to variables.  If X is written by the
1199    parent tree, WRITER is the parent.
1200    We store accesses in one of the two lists: PBEFORE_SP, and PNO_SP.  If this
1201    expression or its only operand forces a sequence point, then everything up
1202    to the sequence point is stored in PBEFORE_SP.  Everything else gets stored
1203    in PNO_SP.
1204    Once we return, we will have emitted warnings if any subexpression before
1205    such a sequence point could be undefined.  On a higher level, however, the
1206    sequence point may not be relevant, and we'll merge the two lists.
1207
1208    Example: (b++, a) + b;
1209    The call that processes the COMPOUND_EXPR will store the increment of B
1210    in PBEFORE_SP, and the use of A in PNO_SP.  The higher-level call that
1211    processes the PLUS_EXPR will need to merge the two lists so that
1212    eventually, all accesses end up on the same list (and we'll warn about the
1213    unordered subexpressions b++ and b.
1214
1215    A note on merging.  If we modify the former example so that our expression
1216    becomes
1217      (b++, b) + a
1218    care must be taken not simply to add all three expressions into the final
1219    PNO_SP list.  The function merge_tlist takes care of that by merging the
1220    before-SP list of the COMPOUND_EXPR into its after-SP list in a special
1221    way, so that no more than one access to B is recorded.  */
1222
1223 static void
1224 verify_tree (x, pbefore_sp, pno_sp, writer)
1225      tree x;
1226      struct tlist **pbefore_sp, **pno_sp;
1227      tree writer;
1228 {
1229   struct tlist *tmp_before, *tmp_nosp, *tmp_list2, *tmp_list3;
1230   enum tree_code code;
1231   char class;
1232
1233   /* X may be NULL if it is the operand of an empty statement expression
1234      ({ }).  */
1235   if (x == NULL)
1236     return;
1237
1238  restart:
1239   code = TREE_CODE (x);
1240   class = TREE_CODE_CLASS (code);
1241
1242   if (warning_candidate_p (x))
1243     {
1244       *pno_sp = new_tlist (*pno_sp, x, writer);
1245       return;
1246     }
1247
1248   switch (code)
1249     {
1250     case CONSTRUCTOR:
1251       return;
1252
1253     case COMPOUND_EXPR:
1254     case TRUTH_ANDIF_EXPR:
1255     case TRUTH_ORIF_EXPR:
1256       tmp_before = tmp_nosp = tmp_list3 = 0;
1257       verify_tree (TREE_OPERAND (x, 0), &tmp_before, &tmp_nosp, NULL_TREE);
1258       warn_for_collisions (tmp_nosp);
1259       merge_tlist (pbefore_sp, tmp_before, 0);
1260       merge_tlist (pbefore_sp, tmp_nosp, 0);
1261       verify_tree (TREE_OPERAND (x, 1), &tmp_list3, pno_sp, NULL_TREE);
1262       merge_tlist (pbefore_sp, tmp_list3, 0);
1263       return;
1264
1265     case COND_EXPR:
1266       tmp_before = tmp_list2 = 0;
1267       verify_tree (TREE_OPERAND (x, 0), &tmp_before, &tmp_list2, NULL_TREE);
1268       warn_for_collisions (tmp_list2);
1269       merge_tlist (pbefore_sp, tmp_before, 0);
1270       merge_tlist (pbefore_sp, tmp_list2, 1);
1271
1272       tmp_list3 = tmp_nosp = 0;
1273       verify_tree (TREE_OPERAND (x, 1), &tmp_list3, &tmp_nosp, NULL_TREE);
1274       warn_for_collisions (tmp_nosp);
1275       merge_tlist (pbefore_sp, tmp_list3, 0);
1276
1277       tmp_list3 = tmp_list2 = 0;
1278       verify_tree (TREE_OPERAND (x, 2), &tmp_list3, &tmp_list2, NULL_TREE);
1279       warn_for_collisions (tmp_list2);
1280       merge_tlist (pbefore_sp, tmp_list3, 0);
1281       /* Rather than add both tmp_nosp and tmp_list2, we have to merge the
1282          two first, to avoid warning for (a ? b++ : b++).  */
1283       merge_tlist (&tmp_nosp, tmp_list2, 0);
1284       add_tlist (pno_sp, tmp_nosp, NULL_TREE, 0);
1285       return;
1286
1287     case PREDECREMENT_EXPR:
1288     case PREINCREMENT_EXPR:
1289     case POSTDECREMENT_EXPR:
1290     case POSTINCREMENT_EXPR:
1291       verify_tree (TREE_OPERAND (x, 0), pno_sp, pno_sp, x);
1292       return;
1293
1294     case MODIFY_EXPR:
1295       tmp_before = tmp_nosp = tmp_list3 = 0;
1296       verify_tree (TREE_OPERAND (x, 1), &tmp_before, &tmp_nosp, NULL_TREE);
1297       verify_tree (TREE_OPERAND (x, 0), &tmp_list3, &tmp_list3, x);
1298       /* Expressions inside the LHS are not ordered wrt. the sequence points
1299          in the RHS.  Example:
1300            *a = (a++, 2)
1301          Despite the fact that the modification of "a" is in the before_sp
1302          list (tmp_before), it conflicts with the use of "a" in the LHS.
1303          We can handle this by adding the contents of tmp_list3
1304          to those of tmp_before, and redoing the collision warnings for that
1305          list.  */
1306       add_tlist (&tmp_before, tmp_list3, x, 1);
1307       warn_for_collisions (tmp_before);
1308       /* Exclude the LHS itself here; we first have to merge it into the
1309          tmp_nosp list.  This is done to avoid warning for "a = a"; if we
1310          didn't exclude the LHS, we'd get it twice, once as a read and once
1311          as a write.  */
1312       add_tlist (pno_sp, tmp_list3, x, 0);
1313       warn_for_collisions_1 (TREE_OPERAND (x, 0), x, tmp_nosp, 1);
1314
1315       merge_tlist (pbefore_sp, tmp_before, 0);
1316       if (warning_candidate_p (TREE_OPERAND (x, 0)))
1317         merge_tlist (&tmp_nosp, new_tlist (NULL, TREE_OPERAND (x, 0), x), 0);
1318       add_tlist (pno_sp, tmp_nosp, NULL_TREE, 1);
1319       return;
1320
1321     case CALL_EXPR:
1322       /* We need to warn about conflicts among arguments and conflicts between
1323          args and the function address.  Side effects of the function address,
1324          however, are not ordered by the sequence point of the call.  */
1325       tmp_before = tmp_nosp = tmp_list2 = tmp_list3 = 0;
1326       verify_tree (TREE_OPERAND (x, 0), &tmp_before, &tmp_nosp, NULL_TREE);
1327       if (TREE_OPERAND (x, 1))
1328         verify_tree (TREE_OPERAND (x, 1), &tmp_list2, &tmp_list3, NULL_TREE);
1329       merge_tlist (&tmp_list3, tmp_list2, 0);
1330       add_tlist (&tmp_before, tmp_list3, NULL_TREE, 0);
1331       add_tlist (&tmp_before, tmp_nosp, NULL_TREE, 0);
1332       warn_for_collisions (tmp_before);
1333       add_tlist (pbefore_sp, tmp_before, NULL_TREE, 0);
1334       return;
1335
1336     case TREE_LIST:
1337       /* Scan all the list, e.g. indices of multi dimensional array.  */
1338       while (x)
1339         {
1340           tmp_before = tmp_nosp = 0;
1341           verify_tree (TREE_VALUE (x), &tmp_before, &tmp_nosp, NULL_TREE);
1342           merge_tlist (&tmp_nosp, tmp_before, 0);
1343           add_tlist (pno_sp, tmp_nosp, NULL_TREE, 0);
1344           x = TREE_CHAIN (x);
1345         }
1346       return;
1347
1348     case SAVE_EXPR:
1349       {
1350         struct tlist_cache *t;
1351         for (t = save_expr_cache; t; t = t->next)
1352           if (t->expr == x)
1353             break;
1354
1355         if (! t)
1356           {
1357             t = (struct tlist_cache *) obstack_alloc (&tlist_obstack,
1358                                                       sizeof *t);
1359             t->next = save_expr_cache;
1360             t->expr = x;
1361             save_expr_cache = t;
1362
1363             tmp_before = tmp_nosp = 0;
1364             verify_tree (TREE_OPERAND (x, 0), &tmp_before, &tmp_nosp, NULL_TREE);
1365             warn_for_collisions (tmp_nosp);
1366
1367             tmp_list3 = 0;
1368             while (tmp_nosp)
1369               {
1370                 struct tlist *t = tmp_nosp;
1371                 tmp_nosp = t->next;
1372                 merge_tlist (&tmp_list3, t, 0);
1373               }
1374             t->cache_before_sp = tmp_before;
1375             t->cache_after_sp = tmp_list3;
1376           }
1377         merge_tlist (pbefore_sp, t->cache_before_sp, 1);
1378         add_tlist (pno_sp, t->cache_after_sp, NULL_TREE, 1);
1379         return;
1380       }
1381     default:
1382       break;
1383     }
1384
1385   if (class == '1')
1386     {
1387       if (first_rtl_op (code) == 0)
1388         return;
1389       x = TREE_OPERAND (x, 0);
1390       writer = 0;
1391       goto restart;
1392     }
1393
1394   switch (class)
1395     {
1396     case 'r':
1397     case '<':
1398     case '2':
1399     case 'b':
1400     case 'e':
1401     case 's':
1402     case 'x':
1403       {
1404         int lp;
1405         int max = first_rtl_op (TREE_CODE (x));
1406         for (lp = 0; lp < max; lp++)
1407           {
1408             tmp_before = tmp_nosp = 0;
1409             verify_tree (TREE_OPERAND (x, lp), &tmp_before, &tmp_nosp, NULL_TREE);
1410             merge_tlist (&tmp_nosp, tmp_before, 0);
1411             add_tlist (pno_sp, tmp_nosp, NULL_TREE, 0);
1412           }
1413         break;
1414       }
1415     }
1416 }
1417
1418 /* Try to warn for undefined behaviour in EXPR due to missing sequence
1419    points.  */
1420
1421 static void
1422 verify_sequence_points (expr)
1423      tree expr;
1424 {
1425   struct tlist *before_sp = 0, *after_sp = 0;
1426
1427   warned_ids = 0;
1428   save_expr_cache = 0;
1429   if (tlist_firstobj == 0)
1430     {
1431       gcc_obstack_init (&tlist_obstack);
1432       tlist_firstobj = obstack_alloc (&tlist_obstack, 0);
1433     }
1434
1435   verify_tree (expr, &before_sp, &after_sp, 0);
1436   warn_for_collisions (after_sp);
1437   obstack_free (&tlist_obstack, tlist_firstobj);
1438 }
1439
1440 tree
1441 c_expand_expr_stmt (expr)
1442      tree expr;
1443 {
1444   /* Do default conversion if safe and possibly important,
1445      in case within ({...}).  */
1446   if ((TREE_CODE (TREE_TYPE (expr)) == ARRAY_TYPE
1447        && (flag_isoc99 || lvalue_p (expr)))
1448       || TREE_CODE (TREE_TYPE (expr)) == FUNCTION_TYPE)
1449     expr = default_conversion (expr);
1450
1451   if (warn_sequence_point)
1452     verify_sequence_points (expr);
1453
1454   if (TREE_TYPE (expr) != error_mark_node
1455       && !COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (expr))
1456       && TREE_CODE (TREE_TYPE (expr)) != ARRAY_TYPE)
1457     error ("expression statement has incomplete type");
1458
1459   last_expr_type = TREE_TYPE (expr);
1460   return add_stmt (build_stmt (EXPR_STMT, expr));
1461 }
1462 \f
1463 /* Validate the expression after `case' and apply default promotions.  */
1464
1465 tree
1466 check_case_value (value)
1467      tree value;
1468 {
1469   if (value == NULL_TREE)
1470     return value;
1471
1472   /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue.  */
1473   STRIP_TYPE_NOPS (value);
1474   /* In C++, the following is allowed:
1475
1476        const int i = 3;
1477        switch (...) { case i: ... }
1478
1479      So, we try to reduce the VALUE to a constant that way.  */
1480   if (c_language == clk_cplusplus)
1481     {
1482       value = decl_constant_value (value);
1483       STRIP_TYPE_NOPS (value);
1484       value = fold (value);
1485     }
1486
1487   if (TREE_CODE (value) != INTEGER_CST
1488       && value != error_mark_node)
1489     {
1490       error ("case label does not reduce to an integer constant");
1491       value = error_mark_node;
1492     }
1493   else
1494     /* Promote char or short to int.  */
1495     value = default_conversion (value);
1496
1497   constant_expression_warning (value);
1498
1499   return value;
1500 }
1501 \f
1502 /* Return an integer type with BITS bits of precision,
1503    that is unsigned if UNSIGNEDP is nonzero, otherwise signed.  */
1504
1505 tree
1506 c_common_type_for_size (bits, unsignedp)
1507      unsigned bits;
1508      int unsignedp;
1509 {
1510   if (bits == TYPE_PRECISION (integer_type_node))
1511     return unsignedp ? unsigned_type_node : integer_type_node;
1512
1513   if (bits == TYPE_PRECISION (signed_char_type_node))
1514     return unsignedp ? unsigned_char_type_node : signed_char_type_node;
1515
1516   if (bits == TYPE_PRECISION (short_integer_type_node))
1517     return unsignedp ? short_unsigned_type_node : short_integer_type_node;
1518
1519   if (bits == TYPE_PRECISION (long_integer_type_node))
1520     return unsignedp ? long_unsigned_type_node : long_integer_type_node;
1521
1522   if (bits == TYPE_PRECISION (long_long_integer_type_node))
1523     return (unsignedp ? long_long_unsigned_type_node
1524             : long_long_integer_type_node);
1525
1526   if (bits == TYPE_PRECISION (widest_integer_literal_type_node))
1527     return (unsignedp ? widest_unsigned_literal_type_node
1528             : widest_integer_literal_type_node);
1529
1530   if (bits <= TYPE_PRECISION (intQI_type_node))
1531     return unsignedp ? unsigned_intQI_type_node : intQI_type_node;
1532
1533   if (bits <= TYPE_PRECISION (intHI_type_node))
1534     return unsignedp ? unsigned_intHI_type_node : intHI_type_node;
1535
1536   if (bits <= TYPE_PRECISION (intSI_type_node))
1537     return unsignedp ? unsigned_intSI_type_node : intSI_type_node;
1538
1539   if (bits <= TYPE_PRECISION (intDI_type_node))
1540     return unsignedp ? unsigned_intDI_type_node : intDI_type_node;
1541
1542   return 0;
1543 }
1544
1545 /* Return a data type that has machine mode MODE.
1546    If the mode is an integer,
1547    then UNSIGNEDP selects between signed and unsigned types.  */
1548
1549 tree
1550 c_common_type_for_mode (mode, unsignedp)
1551      enum machine_mode mode;
1552      int unsignedp;
1553 {
1554   if (mode == TYPE_MODE (integer_type_node))
1555     return unsignedp ? unsigned_type_node : integer_type_node;
1556
1557   if (mode == TYPE_MODE (signed_char_type_node))
1558     return unsignedp ? unsigned_char_type_node : signed_char_type_node;
1559
1560   if (mode == TYPE_MODE (short_integer_type_node))
1561     return unsignedp ? short_unsigned_type_node : short_integer_type_node;
1562
1563   if (mode == TYPE_MODE (long_integer_type_node))
1564     return unsignedp ? long_unsigned_type_node : long_integer_type_node;
1565
1566   if (mode == TYPE_MODE (long_long_integer_type_node))
1567     return unsignedp ? long_long_unsigned_type_node : long_long_integer_type_node;
1568
1569   if (mode == TYPE_MODE (widest_integer_literal_type_node))
1570     return unsignedp ? widest_unsigned_literal_type_node
1571                      : widest_integer_literal_type_node;
1572
1573   if (mode == QImode)
1574     return unsignedp ? unsigned_intQI_type_node : intQI_type_node;
1575
1576   if (mode == HImode)
1577     return unsignedp ? unsigned_intHI_type_node : intHI_type_node;
1578
1579   if (mode == SImode)
1580     return unsignedp ? unsigned_intSI_type_node : intSI_type_node;
1581
1582   if (mode == DImode)
1583     return unsignedp ? unsigned_intDI_type_node : intDI_type_node;
1584
1585 #if HOST_BITS_PER_WIDE_INT >= 64
1586   if (mode == TYPE_MODE (intTI_type_node))
1587     return unsignedp ? unsigned_intTI_type_node : intTI_type_node;
1588 #endif
1589
1590   if (mode == TYPE_MODE (float_type_node))
1591     return float_type_node;
1592
1593   if (mode == TYPE_MODE (double_type_node))
1594     return double_type_node;
1595
1596   if (mode == TYPE_MODE (long_double_type_node))
1597     return long_double_type_node;
1598
1599   if (mode == TYPE_MODE (build_pointer_type (char_type_node)))
1600     return build_pointer_type (char_type_node);
1601
1602   if (mode == TYPE_MODE (build_pointer_type (integer_type_node)))
1603     return build_pointer_type (integer_type_node);
1604
1605   switch (mode)
1606     {
1607     case V16QImode:
1608       return unsignedp ? unsigned_V16QI_type_node : V16QI_type_node;
1609     case V8HImode:
1610       return unsignedp ? unsigned_V8HI_type_node : V8HI_type_node;
1611     case V4SImode:
1612       return unsignedp ? unsigned_V4SI_type_node : V4SI_type_node;
1613     case V2DImode:
1614       return unsignedp ? unsigned_V2DI_type_node : V2DI_type_node;
1615     case V2SImode:
1616       return unsignedp ? unsigned_V2SI_type_node : V2SI_type_node;
1617     case V4HImode:
1618       return unsignedp ? unsigned_V4HI_type_node : V4HI_type_node;
1619     case V8QImode:
1620       return unsignedp ? unsigned_V8QI_type_node : V8QI_type_node;
1621     case V16SFmode:
1622       return V16SF_type_node;
1623     case V4SFmode:
1624       return V4SF_type_node;
1625     case V2SFmode:
1626       return V2SF_type_node;
1627     case V2DFmode:
1628       return V2DF_type_node;
1629     default:
1630       break;
1631     }
1632
1633   return 0;
1634 }
1635
1636 /* Return an unsigned type the same as TYPE in other respects.  */
1637 tree
1638 c_common_unsigned_type (type)
1639      tree type;
1640 {
1641   tree type1 = TYPE_MAIN_VARIANT (type);
1642   if (type1 == signed_char_type_node || type1 == char_type_node)
1643     return unsigned_char_type_node;
1644   if (type1 == integer_type_node)
1645     return unsigned_type_node;
1646   if (type1 == short_integer_type_node)
1647     return short_unsigned_type_node;
1648   if (type1 == long_integer_type_node)
1649     return long_unsigned_type_node;
1650   if (type1 == long_long_integer_type_node)
1651     return long_long_unsigned_type_node;
1652   if (type1 == widest_integer_literal_type_node)
1653     return widest_unsigned_literal_type_node;
1654 #if HOST_BITS_PER_WIDE_INT >= 64
1655   if (type1 == intTI_type_node)
1656     return unsigned_intTI_type_node;
1657 #endif
1658   if (type1 == intDI_type_node)
1659     return unsigned_intDI_type_node;
1660   if (type1 == intSI_type_node)
1661     return unsigned_intSI_type_node;
1662   if (type1 == intHI_type_node)
1663     return unsigned_intHI_type_node;
1664   if (type1 == intQI_type_node)
1665     return unsigned_intQI_type_node;
1666
1667   return c_common_signed_or_unsigned_type (1, type);
1668 }
1669
1670 /* Return a signed type the same as TYPE in other respects.  */
1671
1672 tree
1673 c_common_signed_type (type)
1674      tree type;
1675 {
1676   tree type1 = TYPE_MAIN_VARIANT (type);
1677   if (type1 == unsigned_char_type_node || type1 == char_type_node)
1678     return signed_char_type_node;
1679   if (type1 == unsigned_type_node)
1680     return integer_type_node;
1681   if (type1 == short_unsigned_type_node)
1682     return short_integer_type_node;
1683   if (type1 == long_unsigned_type_node)
1684     return long_integer_type_node;
1685   if (type1 == long_long_unsigned_type_node)
1686     return long_long_integer_type_node;
1687   if (type1 == widest_unsigned_literal_type_node)
1688     return widest_integer_literal_type_node;
1689 #if HOST_BITS_PER_WIDE_INT >= 64
1690   if (type1 == unsigned_intTI_type_node)
1691     return intTI_type_node;
1692 #endif
1693   if (type1 == unsigned_intDI_type_node)
1694     return intDI_type_node;
1695   if (type1 == unsigned_intSI_type_node)
1696     return intSI_type_node;
1697   if (type1 == unsigned_intHI_type_node)
1698     return intHI_type_node;
1699   if (type1 == unsigned_intQI_type_node)
1700     return intQI_type_node;
1701
1702   return c_common_signed_or_unsigned_type (0, type);
1703 }
1704
1705 /* Return a type the same as TYPE except unsigned or
1706    signed according to UNSIGNEDP.  */
1707
1708 tree
1709 c_common_signed_or_unsigned_type (unsignedp, type)
1710      int unsignedp;
1711      tree type;
1712 {
1713   if (! INTEGRAL_TYPE_P (type)
1714       || TREE_UNSIGNED (type) == unsignedp)
1715     return type;
1716
1717   if (TYPE_PRECISION (type) == TYPE_PRECISION (signed_char_type_node))
1718     return unsignedp ? unsigned_char_type_node : signed_char_type_node;
1719   if (TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node))
1720     return unsignedp ? unsigned_type_node : integer_type_node;
1721   if (TYPE_PRECISION (type) == TYPE_PRECISION (short_integer_type_node))
1722     return unsignedp ? short_unsigned_type_node : short_integer_type_node;
1723   if (TYPE_PRECISION (type) == TYPE_PRECISION (long_integer_type_node))
1724     return unsignedp ? long_unsigned_type_node : long_integer_type_node;
1725   if (TYPE_PRECISION (type) == TYPE_PRECISION (long_long_integer_type_node))
1726     return (unsignedp ? long_long_unsigned_type_node
1727             : long_long_integer_type_node);
1728   if (TYPE_PRECISION (type) == TYPE_PRECISION (widest_integer_literal_type_node))
1729     return (unsignedp ? widest_unsigned_literal_type_node
1730             : widest_integer_literal_type_node);
1731
1732 #if HOST_BITS_PER_WIDE_INT >= 64
1733   if (TYPE_PRECISION (type) == TYPE_PRECISION (intTI_type_node))
1734     return unsignedp ? unsigned_intTI_type_node : intTI_type_node;
1735 #endif
1736   if (TYPE_PRECISION (type) == TYPE_PRECISION (intDI_type_node))
1737     return unsignedp ? unsigned_intDI_type_node : intDI_type_node;
1738   if (TYPE_PRECISION (type) == TYPE_PRECISION (intSI_type_node))
1739     return unsignedp ? unsigned_intSI_type_node : intSI_type_node;
1740   if (TYPE_PRECISION (type) == TYPE_PRECISION (intHI_type_node))
1741     return unsignedp ? unsigned_intHI_type_node : intHI_type_node;
1742   if (TYPE_PRECISION (type) == TYPE_PRECISION (intQI_type_node))
1743     return unsignedp ? unsigned_intQI_type_node : intQI_type_node;
1744
1745   return type;
1746 }
1747 \f
1748 /* Return the minimum number of bits needed to represent VALUE in a
1749    signed or unsigned type, UNSIGNEDP says which.  */
1750
1751 unsigned int
1752 min_precision (value, unsignedp)
1753      tree value;
1754      int unsignedp;
1755 {
1756   int log;
1757
1758   /* If the value is negative, compute its negative minus 1.  The latter
1759      adjustment is because the absolute value of the largest negative value
1760      is one larger than the largest positive value.  This is equivalent to
1761      a bit-wise negation, so use that operation instead.  */
1762
1763   if (tree_int_cst_sgn (value) < 0)
1764     value = fold (build1 (BIT_NOT_EXPR, TREE_TYPE (value), value));
1765
1766   /* Return the number of bits needed, taking into account the fact
1767      that we need one more bit for a signed than unsigned type.  */
1768
1769   if (integer_zerop (value))
1770     log = 0;
1771   else
1772     log = tree_floor_log2 (value);
1773
1774   return log + 1 + ! unsignedp;
1775 }
1776 \f
1777 /* Print an error message for invalid operands to arith operation
1778    CODE.  NOP_EXPR is used as a special case (see
1779    c_common_truthvalue_conversion).  */
1780
1781 void
1782 binary_op_error (code)
1783      enum tree_code code;
1784 {
1785   const char *opname;
1786
1787   switch (code)
1788     {
1789     case NOP_EXPR:
1790       error ("invalid truth-value expression");
1791       return;
1792
1793     case PLUS_EXPR:
1794       opname = "+"; break;
1795     case MINUS_EXPR:
1796       opname = "-"; break;
1797     case MULT_EXPR:
1798       opname = "*"; break;
1799     case MAX_EXPR:
1800       opname = "max"; break;
1801     case MIN_EXPR:
1802       opname = "min"; break;
1803     case EQ_EXPR:
1804       opname = "=="; break;
1805     case NE_EXPR:
1806       opname = "!="; break;
1807     case LE_EXPR:
1808       opname = "<="; break;
1809     case GE_EXPR:
1810       opname = ">="; break;
1811     case LT_EXPR:
1812       opname = "<"; break;
1813     case GT_EXPR:
1814       opname = ">"; break;
1815     case LSHIFT_EXPR:
1816       opname = "<<"; break;
1817     case RSHIFT_EXPR:
1818       opname = ">>"; break;
1819     case TRUNC_MOD_EXPR:
1820     case FLOOR_MOD_EXPR:
1821       opname = "%"; break;
1822     case TRUNC_DIV_EXPR:
1823     case FLOOR_DIV_EXPR:
1824       opname = "/"; break;
1825     case BIT_AND_EXPR:
1826       opname = "&"; break;
1827     case BIT_IOR_EXPR:
1828       opname = "|"; break;
1829     case TRUTH_ANDIF_EXPR:
1830       opname = "&&"; break;
1831     case TRUTH_ORIF_EXPR:
1832       opname = "||"; break;
1833     case BIT_XOR_EXPR:
1834       opname = "^"; break;
1835     case LROTATE_EXPR:
1836     case RROTATE_EXPR:
1837       opname = "rotate"; break;
1838     default:
1839       opname = "unknown"; break;
1840     }
1841   error ("invalid operands to binary %s", opname);
1842 }
1843 \f
1844 /* Subroutine of build_binary_op, used for comparison operations.
1845    See if the operands have both been converted from subword integer types
1846    and, if so, perhaps change them both back to their original type.
1847    This function is also responsible for converting the two operands
1848    to the proper common type for comparison.
1849
1850    The arguments of this function are all pointers to local variables
1851    of build_binary_op: OP0_PTR is &OP0, OP1_PTR is &OP1,
1852    RESTYPE_PTR is &RESULT_TYPE and RESCODE_PTR is &RESULTCODE.
1853
1854    If this function returns nonzero, it means that the comparison has
1855    a constant value.  What this function returns is an expression for
1856    that value.  */
1857
1858 tree
1859 shorten_compare (op0_ptr, op1_ptr, restype_ptr, rescode_ptr)
1860      tree *op0_ptr, *op1_ptr;
1861      tree *restype_ptr;
1862      enum tree_code *rescode_ptr;
1863 {
1864   tree type;
1865   tree op0 = *op0_ptr;
1866   tree op1 = *op1_ptr;
1867   int unsignedp0, unsignedp1;
1868   int real1, real2;
1869   tree primop0, primop1;
1870   enum tree_code code = *rescode_ptr;
1871
1872   /* Throw away any conversions to wider types
1873      already present in the operands.  */
1874
1875   primop0 = get_narrower (op0, &unsignedp0);
1876   primop1 = get_narrower (op1, &unsignedp1);
1877
1878   /* Handle the case that OP0 does not *contain* a conversion
1879      but it *requires* conversion to FINAL_TYPE.  */
1880
1881   if (op0 == primop0 && TREE_TYPE (op0) != *restype_ptr)
1882     unsignedp0 = TREE_UNSIGNED (TREE_TYPE (op0));
1883   if (op1 == primop1 && TREE_TYPE (op1) != *restype_ptr)
1884     unsignedp1 = TREE_UNSIGNED (TREE_TYPE (op1));
1885
1886   /* If one of the operands must be floated, we cannot optimize.  */
1887   real1 = TREE_CODE (TREE_TYPE (primop0)) == REAL_TYPE;
1888   real2 = TREE_CODE (TREE_TYPE (primop1)) == REAL_TYPE;
1889
1890   /* If first arg is constant, swap the args (changing operation
1891      so value is preserved), for canonicalization.  Don't do this if
1892      the second arg is 0.  */
1893
1894   if (TREE_CONSTANT (primop0)
1895       && ! integer_zerop (primop1) && ! real_zerop (primop1))
1896     {
1897       tree tem = primop0;
1898       int temi = unsignedp0;
1899       primop0 = primop1;
1900       primop1 = tem;
1901       tem = op0;
1902       op0 = op1;
1903       op1 = tem;
1904       *op0_ptr = op0;
1905       *op1_ptr = op1;
1906       unsignedp0 = unsignedp1;
1907       unsignedp1 = temi;
1908       temi = real1;
1909       real1 = real2;
1910       real2 = temi;
1911
1912       switch (code)
1913         {
1914         case LT_EXPR:
1915           code = GT_EXPR;
1916           break;
1917         case GT_EXPR:
1918           code = LT_EXPR;
1919           break;
1920         case LE_EXPR:
1921           code = GE_EXPR;
1922           break;
1923         case GE_EXPR:
1924           code = LE_EXPR;
1925           break;
1926         default:
1927           break;
1928         }
1929       *rescode_ptr = code;
1930     }
1931
1932   /* If comparing an integer against a constant more bits wide,
1933      maybe we can deduce a value of 1 or 0 independent of the data.
1934      Or else truncate the constant now
1935      rather than extend the variable at run time.
1936
1937      This is only interesting if the constant is the wider arg.
1938      Also, it is not safe if the constant is unsigned and the
1939      variable arg is signed, since in this case the variable
1940      would be sign-extended and then regarded as unsigned.
1941      Our technique fails in this case because the lowest/highest
1942      possible unsigned results don't follow naturally from the
1943      lowest/highest possible values of the variable operand.
1944      For just EQ_EXPR and NE_EXPR there is another technique that
1945      could be used: see if the constant can be faithfully represented
1946      in the other operand's type, by truncating it and reextending it
1947      and see if that preserves the constant's value.  */
1948
1949   if (!real1 && !real2
1950       && TREE_CODE (primop1) == INTEGER_CST
1951       && TYPE_PRECISION (TREE_TYPE (primop0)) < TYPE_PRECISION (*restype_ptr))
1952     {
1953       int min_gt, max_gt, min_lt, max_lt;
1954       tree maxval, minval;
1955       /* 1 if comparison is nominally unsigned.  */
1956       int unsignedp = TREE_UNSIGNED (*restype_ptr);
1957       tree val;
1958
1959       type = c_common_signed_or_unsigned_type (unsignedp0,
1960                                                TREE_TYPE (primop0));
1961
1962       /* If TYPE is an enumeration, then we need to get its min/max
1963          values from it's underlying integral type, not the enumerated
1964          type itself.  */
1965       if (TREE_CODE (type) == ENUMERAL_TYPE)
1966         type = c_common_type_for_size (TYPE_PRECISION (type), unsignedp0);
1967
1968       maxval = TYPE_MAX_VALUE (type);
1969       minval = TYPE_MIN_VALUE (type);
1970
1971       if (unsignedp && !unsignedp0)
1972         *restype_ptr = c_common_signed_type (*restype_ptr);
1973
1974       if (TREE_TYPE (primop1) != *restype_ptr)
1975         primop1 = convert (*restype_ptr, primop1);
1976       if (type != *restype_ptr)
1977         {
1978           minval = convert (*restype_ptr, minval);
1979           maxval = convert (*restype_ptr, maxval);
1980         }
1981
1982       if (unsignedp && unsignedp0)
1983         {
1984           min_gt = INT_CST_LT_UNSIGNED (primop1, minval);
1985           max_gt = INT_CST_LT_UNSIGNED (primop1, maxval);
1986           min_lt = INT_CST_LT_UNSIGNED (minval, primop1);
1987           max_lt = INT_CST_LT_UNSIGNED (maxval, primop1);
1988         }
1989       else
1990         {
1991           min_gt = INT_CST_LT (primop1, minval);
1992           max_gt = INT_CST_LT (primop1, maxval);
1993           min_lt = INT_CST_LT (minval, primop1);
1994           max_lt = INT_CST_LT (maxval, primop1);
1995         }
1996
1997       val = 0;
1998       /* This used to be a switch, but Genix compiler can't handle that.  */
1999       if (code == NE_EXPR)
2000         {
2001           if (max_lt || min_gt)
2002             val = boolean_true_node;
2003         }
2004       else if (code == EQ_EXPR)
2005         {
2006           if (max_lt || min_gt)
2007             val = boolean_false_node;
2008         }
2009       else if (code == LT_EXPR)
2010         {
2011           if (max_lt)
2012             val = boolean_true_node;
2013           if (!min_lt)
2014             val = boolean_false_node;
2015         }
2016       else if (code == GT_EXPR)
2017         {
2018           if (min_gt)
2019             val = boolean_true_node;
2020           if (!max_gt)
2021             val = boolean_false_node;
2022         }
2023       else if (code == LE_EXPR)
2024         {
2025           if (!max_gt)
2026             val = boolean_true_node;
2027           if (min_gt)
2028             val = boolean_false_node;
2029         }
2030       else if (code == GE_EXPR)
2031         {
2032           if (!min_lt)
2033             val = boolean_true_node;
2034           if (max_lt)
2035             val = boolean_false_node;
2036         }
2037
2038       /* If primop0 was sign-extended and unsigned comparison specd,
2039          we did a signed comparison above using the signed type bounds.
2040          But the comparison we output must be unsigned.
2041
2042          Also, for inequalities, VAL is no good; but if the signed
2043          comparison had *any* fixed result, it follows that the
2044          unsigned comparison just tests the sign in reverse
2045          (positive values are LE, negative ones GE).
2046          So we can generate an unsigned comparison
2047          against an extreme value of the signed type.  */
2048
2049       if (unsignedp && !unsignedp0)
2050         {
2051           if (val != 0)
2052             switch (code)
2053               {
2054               case LT_EXPR:
2055               case GE_EXPR:
2056                 primop1 = TYPE_MIN_VALUE (type);
2057                 val = 0;
2058                 break;
2059
2060               case LE_EXPR:
2061               case GT_EXPR:
2062                 primop1 = TYPE_MAX_VALUE (type);
2063                 val = 0;
2064                 break;
2065
2066               default:
2067                 break;
2068               }
2069           type = c_common_unsigned_type (type);
2070         }
2071
2072       if (TREE_CODE (primop0) != INTEGER_CST)
2073         {
2074           if (val == boolean_false_node)
2075             warning ("comparison is always false due to limited range of data type");
2076           if (val == boolean_true_node)
2077             warning ("comparison is always true due to limited range of data type");
2078         }
2079
2080       if (val != 0)
2081         {
2082           /* Don't forget to evaluate PRIMOP0 if it has side effects.  */
2083           if (TREE_SIDE_EFFECTS (primop0))
2084             return build (COMPOUND_EXPR, TREE_TYPE (val), primop0, val);
2085           return val;
2086         }
2087
2088       /* Value is not predetermined, but do the comparison
2089          in the type of the operand that is not constant.
2090          TYPE is already properly set.  */
2091     }
2092   else if (real1 && real2
2093            && (TYPE_PRECISION (TREE_TYPE (primop0))
2094                == TYPE_PRECISION (TREE_TYPE (primop1))))
2095     type = TREE_TYPE (primop0);
2096
2097   /* If args' natural types are both narrower than nominal type
2098      and both extend in the same manner, compare them
2099      in the type of the wider arg.
2100      Otherwise must actually extend both to the nominal
2101      common type lest different ways of extending
2102      alter the result.
2103      (eg, (short)-1 == (unsigned short)-1  should be 0.)  */
2104
2105   else if (unsignedp0 == unsignedp1 && real1 == real2
2106            && TYPE_PRECISION (TREE_TYPE (primop0)) < TYPE_PRECISION (*restype_ptr)
2107            && TYPE_PRECISION (TREE_TYPE (primop1)) < TYPE_PRECISION (*restype_ptr))
2108     {
2109       type = common_type (TREE_TYPE (primop0), TREE_TYPE (primop1));
2110       type = c_common_signed_or_unsigned_type (unsignedp0
2111                                                || TREE_UNSIGNED (*restype_ptr),
2112                                                type);
2113       /* Make sure shorter operand is extended the right way
2114          to match the longer operand.  */
2115       primop0
2116         = convert (c_common_signed_or_unsigned_type (unsignedp0,
2117                                                      TREE_TYPE (primop0)),
2118                    primop0);
2119       primop1
2120         = convert (c_common_signed_or_unsigned_type (unsignedp1,
2121                                                      TREE_TYPE (primop1)),
2122                    primop1);
2123     }
2124   else
2125     {
2126       /* Here we must do the comparison on the nominal type
2127          using the args exactly as we received them.  */
2128       type = *restype_ptr;
2129       primop0 = op0;
2130       primop1 = op1;
2131
2132       if (!real1 && !real2 && integer_zerop (primop1)
2133           && TREE_UNSIGNED (*restype_ptr))
2134         {
2135           tree value = 0;
2136           switch (code)
2137             {
2138             case GE_EXPR:
2139               /* All unsigned values are >= 0, so we warn if extra warnings
2140                  are requested.  However, if OP0 is a constant that is
2141                  >= 0, the signedness of the comparison isn't an issue,
2142                  so suppress the warning.  */
2143               if (extra_warnings && !in_system_header
2144                   && ! (TREE_CODE (primop0) == INTEGER_CST
2145                         && ! TREE_OVERFLOW (convert (c_common_signed_type (type),
2146                                                      primop0))))
2147                 warning ("comparison of unsigned expression >= 0 is always true");
2148               value = boolean_true_node;
2149               break;
2150
2151             case LT_EXPR:
2152               if (extra_warnings && !in_system_header
2153                   && ! (TREE_CODE (primop0) == INTEGER_CST
2154                         && ! TREE_OVERFLOW (convert (c_common_signed_type (type),
2155                                                      primop0))))
2156                 warning ("comparison of unsigned expression < 0 is always false");
2157               value = boolean_false_node;
2158               break;
2159
2160             default:
2161               break;
2162             }
2163
2164           if (value != 0)
2165             {
2166               /* Don't forget to evaluate PRIMOP0 if it has side effects.  */
2167               if (TREE_SIDE_EFFECTS (primop0))
2168                 return build (COMPOUND_EXPR, TREE_TYPE (value),
2169                               primop0, value);
2170               return value;
2171             }
2172         }
2173     }
2174
2175   *op0_ptr = convert (type, primop0);
2176   *op1_ptr = convert (type, primop1);
2177
2178   *restype_ptr = boolean_type_node;
2179
2180   return 0;
2181 }
2182 \f
2183 /* Return a tree for the sum or difference (RESULTCODE says which)
2184    of pointer PTROP and integer INTOP.  */
2185
2186 tree
2187 pointer_int_sum (resultcode, ptrop, intop)
2188      enum tree_code resultcode;
2189      tree ptrop, intop;
2190 {
2191   tree size_exp;
2192
2193   tree result;
2194   tree folded;
2195
2196   /* The result is a pointer of the same type that is being added.  */
2197
2198   tree result_type = TREE_TYPE (ptrop);
2199
2200   if (TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE)
2201     {
2202       if (pedantic || warn_pointer_arith)
2203         pedwarn ("pointer of type `void *' used in arithmetic");
2204       size_exp = integer_one_node;
2205     }
2206   else if (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE)
2207     {
2208       if (pedantic || warn_pointer_arith)
2209         pedwarn ("pointer to a function used in arithmetic");
2210       size_exp = integer_one_node;
2211     }
2212   else if (TREE_CODE (TREE_TYPE (result_type)) == METHOD_TYPE)
2213     {
2214       if (pedantic || warn_pointer_arith)
2215         pedwarn ("pointer to member function used in arithmetic");
2216       size_exp = integer_one_node;
2217     }
2218   else if (TREE_CODE (TREE_TYPE (result_type)) == OFFSET_TYPE)
2219     {
2220       if (pedantic || warn_pointer_arith)
2221         pedwarn ("pointer to a member used in arithmetic");
2222       size_exp = integer_one_node;
2223     }
2224   else
2225     size_exp = size_in_bytes (TREE_TYPE (result_type));
2226
2227   /* If what we are about to multiply by the size of the elements
2228      contains a constant term, apply distributive law
2229      and multiply that constant term separately.
2230      This helps produce common subexpressions.  */
2231
2232   if ((TREE_CODE (intop) == PLUS_EXPR || TREE_CODE (intop) == MINUS_EXPR)
2233       && ! TREE_CONSTANT (intop)
2234       && TREE_CONSTANT (TREE_OPERAND (intop, 1))
2235       && TREE_CONSTANT (size_exp)
2236       /* If the constant comes from pointer subtraction,
2237          skip this optimization--it would cause an error.  */
2238       && TREE_CODE (TREE_TYPE (TREE_OPERAND (intop, 0))) == INTEGER_TYPE
2239       /* If the constant is unsigned, and smaller than the pointer size,
2240          then we must skip this optimization.  This is because it could cause
2241          an overflow error if the constant is negative but INTOP is not.  */
2242       && (! TREE_UNSIGNED (TREE_TYPE (intop))
2243           || (TYPE_PRECISION (TREE_TYPE (intop))
2244               == TYPE_PRECISION (TREE_TYPE (ptrop)))))
2245     {
2246       enum tree_code subcode = resultcode;
2247       tree int_type = TREE_TYPE (intop);
2248       if (TREE_CODE (intop) == MINUS_EXPR)
2249         subcode = (subcode == PLUS_EXPR ? MINUS_EXPR : PLUS_EXPR);
2250       /* Convert both subexpression types to the type of intop,
2251          because weird cases involving pointer arithmetic
2252          can result in a sum or difference with different type args.  */
2253       ptrop = build_binary_op (subcode, ptrop,
2254                                convert (int_type, TREE_OPERAND (intop, 1)), 1);
2255       intop = convert (int_type, TREE_OPERAND (intop, 0));
2256     }
2257
2258   /* Convert the integer argument to a type the same size as sizetype
2259      so the multiply won't overflow spuriously.  */
2260
2261   if (TYPE_PRECISION (TREE_TYPE (intop)) != TYPE_PRECISION (sizetype)
2262       || TREE_UNSIGNED (TREE_TYPE (intop)) != TREE_UNSIGNED (sizetype))
2263     intop = convert (c_common_type_for_size (TYPE_PRECISION (sizetype),
2264                                              TREE_UNSIGNED (sizetype)), intop);
2265
2266   /* Replace the integer argument with a suitable product by the object size.
2267      Do this multiplication as signed, then convert to the appropriate
2268      pointer type (actually unsigned integral).  */
2269
2270   intop = convert (result_type,
2271                    build_binary_op (MULT_EXPR, intop,
2272                                     convert (TREE_TYPE (intop), size_exp), 1));
2273
2274   /* Create the sum or difference.  */
2275
2276   result = build (resultcode, result_type, ptrop, intop);
2277
2278   folded = fold (result);
2279   if (folded == result)
2280     TREE_CONSTANT (folded) = TREE_CONSTANT (ptrop) & TREE_CONSTANT (intop);
2281   return folded;
2282 }
2283 \f
2284 /* Prepare expr to be an argument of a TRUTH_NOT_EXPR,
2285    or validate its data type for an `if' or `while' statement or ?..: exp.
2286
2287    This preparation consists of taking the ordinary
2288    representation of an expression expr and producing a valid tree
2289    boolean expression describing whether expr is nonzero.  We could
2290    simply always do build_binary_op (NE_EXPR, expr, boolean_false_node, 1),
2291    but we optimize comparisons, &&, ||, and !.
2292
2293    The resulting type should always be `boolean_type_node'.  */
2294
2295 tree
2296 c_common_truthvalue_conversion (expr)
2297      tree expr;
2298 {
2299   if (TREE_CODE (expr) == ERROR_MARK)
2300     return expr;
2301
2302 #if 0 /* This appears to be wrong for C++.  */
2303   /* These really should return error_mark_node after 2.4 is stable.
2304      But not all callers handle ERROR_MARK properly.  */
2305   switch (TREE_CODE (TREE_TYPE (expr)))
2306     {
2307     case RECORD_TYPE:
2308       error ("struct type value used where scalar is required");
2309       return boolean_false_node;
2310
2311     case UNION_TYPE:
2312       error ("union type value used where scalar is required");
2313       return boolean_false_node;
2314
2315     case ARRAY_TYPE:
2316       error ("array type value used where scalar is required");
2317       return boolean_false_node;
2318
2319     default:
2320       break;
2321     }
2322 #endif /* 0 */
2323
2324   switch (TREE_CODE (expr))
2325     {
2326     case EQ_EXPR:
2327     case NE_EXPR: case LE_EXPR: case GE_EXPR: case LT_EXPR: case GT_EXPR:
2328     case TRUTH_ANDIF_EXPR:
2329     case TRUTH_ORIF_EXPR:
2330     case TRUTH_AND_EXPR:
2331     case TRUTH_OR_EXPR:
2332     case TRUTH_XOR_EXPR:
2333     case TRUTH_NOT_EXPR:
2334       TREE_TYPE (expr) = boolean_type_node;
2335       return expr;
2336
2337     case ERROR_MARK:
2338       return expr;
2339
2340     case INTEGER_CST:
2341       return integer_zerop (expr) ? boolean_false_node : boolean_true_node;
2342
2343     case REAL_CST:
2344       return real_zerop (expr) ? boolean_false_node : boolean_true_node;
2345
2346     case ADDR_EXPR:
2347       /* If we are taking the address of an external decl, it might be zero
2348          if it is weak, so we cannot optimize.  */
2349       if (DECL_P (TREE_OPERAND (expr, 0))
2350           && DECL_EXTERNAL (TREE_OPERAND (expr, 0)))
2351         break;
2352
2353       if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 0)))
2354         return build (COMPOUND_EXPR, boolean_type_node,
2355                       TREE_OPERAND (expr, 0), boolean_true_node);
2356       else
2357         return boolean_true_node;
2358
2359     case COMPLEX_EXPR:
2360       return build_binary_op ((TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 1))
2361                                ? TRUTH_OR_EXPR : TRUTH_ORIF_EXPR),
2362                 c_common_truthvalue_conversion (TREE_OPERAND (expr, 0)),
2363                 c_common_truthvalue_conversion (TREE_OPERAND (expr, 1)),
2364                               0);
2365
2366     case NEGATE_EXPR:
2367     case ABS_EXPR:
2368     case FLOAT_EXPR:
2369     case FFS_EXPR:
2370       /* These don't change whether an object is non-zero or zero.  */
2371       return c_common_truthvalue_conversion (TREE_OPERAND (expr, 0));
2372
2373     case LROTATE_EXPR:
2374     case RROTATE_EXPR:
2375       /* These don't change whether an object is zero or non-zero, but
2376          we can't ignore them if their second arg has side-effects.  */
2377       if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 1)))
2378         return build (COMPOUND_EXPR, boolean_type_node, TREE_OPERAND (expr, 1),
2379                       c_common_truthvalue_conversion (TREE_OPERAND (expr, 0)));
2380       else
2381         return c_common_truthvalue_conversion (TREE_OPERAND (expr, 0));
2382
2383     case COND_EXPR:
2384       /* Distribute the conversion into the arms of a COND_EXPR.  */
2385       return fold (build (COND_EXPR, boolean_type_node, TREE_OPERAND (expr, 0),
2386                 c_common_truthvalue_conversion (TREE_OPERAND (expr, 1)),
2387                 c_common_truthvalue_conversion (TREE_OPERAND (expr, 2))));
2388
2389     case CONVERT_EXPR:
2390       /* Don't cancel the effect of a CONVERT_EXPR from a REFERENCE_TYPE,
2391          since that affects how `default_conversion' will behave.  */
2392       if (TREE_CODE (TREE_TYPE (expr)) == REFERENCE_TYPE
2393           || TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == REFERENCE_TYPE)
2394         break;
2395       /* fall through...  */
2396     case NOP_EXPR:
2397       /* If this is widening the argument, we can ignore it.  */
2398       if (TYPE_PRECISION (TREE_TYPE (expr))
2399           >= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (expr, 0))))
2400         return c_common_truthvalue_conversion (TREE_OPERAND (expr, 0));
2401       break;
2402
2403     case MINUS_EXPR:
2404       /* Perhaps reduce (x - y) != 0 to (x != y).  The expressions
2405          aren't guaranteed to the be same for modes that can represent
2406          infinity, since if x and y are both +infinity, or both
2407          -infinity, then x - y is not a number.
2408
2409          Note that this transformation is safe when x or y is NaN.
2410          (x - y) is then NaN, and both (x - y) != 0 and x != y will
2411          be false.  */
2412       if (HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (TREE_OPERAND (expr, 0)))))
2413         break;
2414       /* fall through...  */
2415     case BIT_XOR_EXPR:
2416       /* This and MINUS_EXPR can be changed into a comparison of the
2417          two objects.  */
2418       if (TREE_TYPE (TREE_OPERAND (expr, 0))
2419           == TREE_TYPE (TREE_OPERAND (expr, 1)))
2420         return build_binary_op (NE_EXPR, TREE_OPERAND (expr, 0),
2421                                 TREE_OPERAND (expr, 1), 1);
2422       return build_binary_op (NE_EXPR, TREE_OPERAND (expr, 0),
2423                               fold (build1 (NOP_EXPR,
2424                                             TREE_TYPE (TREE_OPERAND (expr, 0)),
2425                                             TREE_OPERAND (expr, 1))), 1);
2426
2427     case BIT_AND_EXPR:
2428       if (integer_onep (TREE_OPERAND (expr, 1))
2429           && TREE_TYPE (expr) != boolean_type_node)
2430         /* Using convert here would cause infinite recursion.  */
2431         return build1 (NOP_EXPR, boolean_type_node, expr);
2432       break;
2433
2434     case MODIFY_EXPR:
2435       if (warn_parentheses && C_EXP_ORIGINAL_CODE (expr) == MODIFY_EXPR)
2436         warning ("suggest parentheses around assignment used as truth value");
2437       break;
2438
2439     default:
2440       break;
2441     }
2442
2443   if (TREE_CODE (TREE_TYPE (expr)) == COMPLEX_TYPE)
2444     {
2445       tree t = save_expr (expr);
2446       return (build_binary_op
2447               ((TREE_SIDE_EFFECTS (expr)
2448                 ? TRUTH_OR_EXPR : TRUTH_ORIF_EXPR),
2449         c_common_truthvalue_conversion (build_unary_op (REALPART_EXPR, t, 0)),
2450         c_common_truthvalue_conversion (build_unary_op (IMAGPART_EXPR, t, 0)),
2451                0));
2452     }
2453
2454   return build_binary_op (NE_EXPR, expr, integer_zero_node, 1);
2455 }
2456 \f
2457 static tree builtin_function_2 PARAMS ((const char *, const char *, tree, tree,
2458                                         int, enum built_in_class, int, int,
2459                                         tree));
2460
2461 /* Make a variant type in the proper way for C/C++, propagating qualifiers
2462    down to the element type of an array.  */
2463
2464 tree
2465 c_build_qualified_type (type, type_quals)
2466      tree type;
2467      int type_quals;
2468 {
2469   /* A restrict-qualified pointer type must be a pointer to object or
2470      incomplete type.  Note that the use of POINTER_TYPE_P also allows
2471      REFERENCE_TYPEs, which is appropriate for C++.  Unfortunately,
2472      the C++ front-end also use POINTER_TYPE for pointer-to-member
2473      values, so even though it should be illegal to use `restrict'
2474      with such an entity we don't flag that here.  Thus, special case
2475      code for that case is required in the C++ front-end.  */
2476   if ((type_quals & TYPE_QUAL_RESTRICT)
2477       && (!POINTER_TYPE_P (type)
2478           || !C_TYPE_OBJECT_OR_INCOMPLETE_P (TREE_TYPE (type))))
2479     {
2480       error ("invalid use of `restrict'");
2481       type_quals &= ~TYPE_QUAL_RESTRICT;
2482     }
2483
2484   if (TREE_CODE (type) == ARRAY_TYPE)
2485     return build_array_type (c_build_qualified_type (TREE_TYPE (type),
2486                                                      type_quals),
2487                              TYPE_DOMAIN (type));
2488   return build_qualified_type (type, type_quals);
2489 }
2490
2491 /* Apply the TYPE_QUALS to the new DECL.  */
2492
2493 void
2494 c_apply_type_quals_to_decl (type_quals, decl)
2495      int type_quals;
2496      tree decl;
2497 {
2498   if ((type_quals & TYPE_QUAL_CONST)
2499       || (TREE_TYPE (decl)
2500           && TREE_CODE (TREE_TYPE (decl)) == REFERENCE_TYPE))
2501     TREE_READONLY (decl) = 1;
2502   if (type_quals & TYPE_QUAL_VOLATILE)
2503     {
2504       TREE_SIDE_EFFECTS (decl) = 1;
2505       TREE_THIS_VOLATILE (decl) = 1;
2506     }
2507   if (type_quals & TYPE_QUAL_RESTRICT)
2508     {
2509       if (!TREE_TYPE (decl)
2510           || !POINTER_TYPE_P (TREE_TYPE (decl))
2511           || !C_TYPE_OBJECT_OR_INCOMPLETE_P (TREE_TYPE (TREE_TYPE (decl))))
2512         error ("invalid use of `restrict'");
2513       else if (flag_strict_aliasing)
2514         /* Indicate we need to make a unique alias set for this pointer.
2515            We can't do it here because it might be pointing to an
2516            incomplete type.  */
2517         DECL_POINTER_ALIAS_SET (decl) = -2;
2518     }
2519 }
2520
2521 /* Return the typed-based alias set for T, which may be an expression
2522    or a type.  Return -1 if we don't do anything special.  */
2523
2524 HOST_WIDE_INT
2525 c_common_get_alias_set (t)
2526      tree t;
2527 {
2528   tree u;
2529
2530   /* Permit type-punning when accessing a union, provided the access
2531      is directly through the union.  For example, this code does not
2532      permit taking the address of a union member and then storing
2533      through it.  Even the type-punning allowed here is a GCC
2534      extension, albeit a common and useful one; the C standard says
2535      that such accesses have implementation-defined behavior.  */
2536   for (u = t;
2537        TREE_CODE (u) == COMPONENT_REF || TREE_CODE (u) == ARRAY_REF;
2538        u = TREE_OPERAND (u, 0))
2539     if (TREE_CODE (u) == COMPONENT_REF
2540         && TREE_CODE (TREE_TYPE (TREE_OPERAND (u, 0))) == UNION_TYPE)
2541       return 0;
2542
2543   /* That's all the expressions we handle specially.  */
2544   if (! TYPE_P (t))
2545     return -1;
2546
2547   /* The C standard guarantess that any object may be accessed via an
2548      lvalue that has character type.  */
2549   if (t == char_type_node
2550       || t == signed_char_type_node
2551       || t == unsigned_char_type_node)
2552     return 0;
2553
2554   /* If it has the may_alias attribute, it can alias anything.  */
2555   if (lookup_attribute ("may_alias", TYPE_ATTRIBUTES (t)))
2556     return 0;
2557
2558   /* The C standard specifically allows aliasing between signed and
2559      unsigned variants of the same type.  We treat the signed
2560      variant as canonical.  */
2561   if (TREE_CODE (t) == INTEGER_TYPE && TREE_UNSIGNED (t))
2562     {
2563       tree t1 = c_common_signed_type (t);
2564
2565       /* t1 == t can happen for boolean nodes which are always unsigned.  */
2566       if (t1 != t)
2567         return get_alias_set (t1);
2568     }
2569   else if (POINTER_TYPE_P (t))
2570     {
2571       tree t1;
2572
2573       /* Unfortunately, there is no canonical form of a pointer type.
2574          In particular, if we have `typedef int I', then `int *', and
2575          `I *' are different types.  So, we have to pick a canonical
2576          representative.  We do this below.
2577
2578          Technically, this approach is actually more conservative that
2579          it needs to be.  In particular, `const int *' and `int *'
2580          should be in different alias sets, according to the C and C++
2581          standard, since their types are not the same, and so,
2582          technically, an `int **' and `const int **' cannot point at
2583          the same thing.
2584
2585          But, the standard is wrong.  In particular, this code is
2586          legal C++:
2587
2588             int *ip;
2589             int **ipp = &ip;
2590             const int* const* cipp = &ipp;
2591
2592          And, it doesn't make sense for that to be legal unless you
2593          can dereference IPP and CIPP.  So, we ignore cv-qualifiers on
2594          the pointed-to types.  This issue has been reported to the
2595          C++ committee.  */
2596       t1 = build_type_no_quals (t);
2597       if (t1 != t)
2598         return get_alias_set (t1);
2599     }
2600
2601   return -1;
2602 }
2603 \f
2604 /* Implement the __alignof keyword: Return the minimum required
2605    alignment of TYPE, measured in bytes.  */
2606
2607 tree
2608 c_alignof (type)
2609      tree type;
2610 {
2611   enum tree_code code = TREE_CODE (type);
2612   tree t;
2613
2614   /* In C++, sizeof applies to the referent.  Handle alignof the same way.  */
2615   if (code == REFERENCE_TYPE)
2616     {
2617       type = TREE_TYPE (type);
2618       code = TREE_CODE (type);
2619     }
2620
2621   if (code == FUNCTION_TYPE)
2622     t = size_int (FUNCTION_BOUNDARY / BITS_PER_UNIT);
2623   else if (code == VOID_TYPE || code == ERROR_MARK)
2624     t = size_one_node;
2625   else if (!COMPLETE_TYPE_P (type))
2626     {
2627       error ("__alignof__ applied to an incomplete type");
2628       t = size_zero_node;
2629     }
2630   else
2631     t = size_int (TYPE_ALIGN (type) / BITS_PER_UNIT);
2632
2633   return fold (build1 (NOP_EXPR, c_size_type_node, t));
2634 }
2635
2636 /* Implement the __alignof keyword: Return the minimum required
2637    alignment of EXPR, measured in bytes.  For VAR_DECL's and
2638    FIELD_DECL's return DECL_ALIGN (which can be set from an
2639    "aligned" __attribute__ specification).  */
2640
2641 tree
2642 c_alignof_expr (expr)
2643      tree expr;
2644 {
2645   tree t;
2646
2647   if (TREE_CODE (expr) == VAR_DECL)
2648     t = size_int (DECL_ALIGN (expr) / BITS_PER_UNIT);
2649
2650   else if (TREE_CODE (expr) == COMPONENT_REF
2651            && DECL_C_BIT_FIELD (TREE_OPERAND (expr, 1)))
2652     {
2653       error ("`__alignof' applied to a bit-field");
2654       t = size_one_node;
2655     }
2656   else if (TREE_CODE (expr) == COMPONENT_REF
2657            && TREE_CODE (TREE_OPERAND (expr, 1)) == FIELD_DECL)
2658     t = size_int (DECL_ALIGN (TREE_OPERAND (expr, 1)) / BITS_PER_UNIT);
2659
2660   else if (TREE_CODE (expr) == INDIRECT_REF)
2661     {
2662       tree t = TREE_OPERAND (expr, 0);
2663       tree best = t;
2664       int bestalign = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (t)));
2665
2666       while (TREE_CODE (t) == NOP_EXPR
2667              && TREE_CODE (TREE_TYPE (TREE_OPERAND (t, 0))) == POINTER_TYPE)
2668         {
2669           int thisalign;
2670
2671           t = TREE_OPERAND (t, 0);
2672           thisalign = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (t)));
2673           if (thisalign > bestalign)
2674             best = t, bestalign = thisalign;
2675         }
2676       return c_alignof (TREE_TYPE (TREE_TYPE (best)));
2677     }
2678   else
2679     return c_alignof (TREE_TYPE (expr));
2680
2681   return fold (build1 (NOP_EXPR, c_size_type_node, t));
2682 }
2683 \f
2684 /* Handle C and C++ default attributes.  */
2685
2686 enum built_in_attribute
2687 {
2688 #define DEF_ATTR_NULL_TREE(ENUM) ENUM,
2689 #define DEF_ATTR_INT(ENUM, VALUE) ENUM,
2690 #define DEF_ATTR_IDENT(ENUM, STRING) ENUM,
2691 #define DEF_ATTR_TREE_LIST(ENUM, PURPOSE, VALUE, CHAIN) ENUM,
2692 #define DEF_FN_ATTR(NAME, ATTRS, PREDICATE) /* No entry needed in enum.  */
2693 #include "builtin-attrs.def"
2694 #undef DEF_ATTR_NULL_TREE
2695 #undef DEF_ATTR_INT
2696 #undef DEF_ATTR_IDENT
2697 #undef DEF_ATTR_TREE_LIST
2698 #undef DEF_FN_ATTR
2699   ATTR_LAST
2700 };
2701
2702 static GTY(()) tree built_in_attributes[(int) ATTR_LAST];
2703
2704 static bool c_attrs_initialized = false;
2705
2706 static void c_init_attributes PARAMS ((void));
2707
2708 /* Build tree nodes and builtin functions common to both C and C++ language
2709    frontends.  */
2710
2711 void
2712 c_common_nodes_and_builtins ()
2713 {
2714   enum builtin_type
2715   {
2716 #define DEF_PRIMITIVE_TYPE(NAME, VALUE) NAME,
2717 #define DEF_FUNCTION_TYPE_0(NAME, RETURN) NAME,
2718 #define DEF_FUNCTION_TYPE_1(NAME, RETURN, ARG1) NAME,
2719 #define DEF_FUNCTION_TYPE_2(NAME, RETURN, ARG1, ARG2) NAME,
2720 #define DEF_FUNCTION_TYPE_3(NAME, RETURN, ARG1, ARG2, ARG3) NAME,
2721 #define DEF_FUNCTION_TYPE_4(NAME, RETURN, ARG1, ARG2, ARG3, ARG4) NAME,
2722 #define DEF_FUNCTION_TYPE_VAR_0(NAME, RETURN) NAME,
2723 #define DEF_FUNCTION_TYPE_VAR_1(NAME, RETURN, ARG1) NAME,
2724 #define DEF_FUNCTION_TYPE_VAR_2(NAME, RETURN, ARG1, ARG2) NAME,
2725 #define DEF_POINTER_TYPE(NAME, TYPE) NAME,
2726 #include "builtin-types.def"
2727 #undef DEF_PRIMITIVE_TYPE
2728 #undef DEF_FUNCTION_TYPE_0
2729 #undef DEF_FUNCTION_TYPE_1
2730 #undef DEF_FUNCTION_TYPE_2
2731 #undef DEF_FUNCTION_TYPE_3
2732 #undef DEF_FUNCTION_TYPE_4
2733 #undef DEF_FUNCTION_TYPE_VAR_0
2734 #undef DEF_FUNCTION_TYPE_VAR_1
2735 #undef DEF_FUNCTION_TYPE_VAR_2
2736 #undef DEF_POINTER_TYPE
2737     BT_LAST
2738   };
2739
2740   typedef enum builtin_type builtin_type;
2741
2742   tree builtin_types[(int) BT_LAST];
2743   int wchar_type_size;
2744   tree array_domain_type;
2745   tree va_list_ref_type_node;
2746   tree va_list_arg_type_node;
2747
2748   /* Define `int' and `char' first so that dbx will output them first.  */
2749   record_builtin_type (RID_INT, NULL, integer_type_node);
2750   record_builtin_type (RID_CHAR, "char", char_type_node);
2751
2752   /* `signed' is the same as `int'.  FIXME: the declarations of "signed",
2753      "unsigned long", "long long unsigned" and "unsigned short" were in C++
2754      but not C.  Are the conditionals here needed?  */
2755   if (c_language == clk_cplusplus)
2756     record_builtin_type (RID_SIGNED, NULL, integer_type_node);
2757   record_builtin_type (RID_LONG, "long int", long_integer_type_node);
2758   record_builtin_type (RID_UNSIGNED, "unsigned int", unsigned_type_node);
2759   record_builtin_type (RID_MAX, "long unsigned int",
2760                        long_unsigned_type_node);
2761   if (c_language == clk_cplusplus)
2762     record_builtin_type (RID_MAX, "unsigned long", long_unsigned_type_node);
2763   record_builtin_type (RID_MAX, "long long int",
2764                        long_long_integer_type_node);
2765   record_builtin_type (RID_MAX, "long long unsigned int",
2766                        long_long_unsigned_type_node);
2767   if (c_language == clk_cplusplus)
2768     record_builtin_type (RID_MAX, "long long unsigned",
2769                          long_long_unsigned_type_node);
2770   record_builtin_type (RID_SHORT, "short int", short_integer_type_node);
2771   record_builtin_type (RID_MAX, "short unsigned int",
2772                        short_unsigned_type_node);
2773   if (c_language == clk_cplusplus)
2774     record_builtin_type (RID_MAX, "unsigned short",
2775                          short_unsigned_type_node);
2776
2777   /* Define both `signed char' and `unsigned char'.  */
2778   record_builtin_type (RID_MAX, "signed char", signed_char_type_node);
2779   record_builtin_type (RID_MAX, "unsigned char", unsigned_char_type_node);
2780
2781   /* These are types that c_common_type_for_size and
2782      c_common_type_for_mode use.  */
2783   (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL, NULL_TREE,
2784                                             intQI_type_node));
2785   (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL, NULL_TREE,
2786                                             intHI_type_node));
2787   (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL, NULL_TREE,
2788                                             intSI_type_node));
2789   (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL, NULL_TREE,
2790                                             intDI_type_node));
2791 #if HOST_BITS_PER_WIDE_INT >= 64
2792   (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL,
2793                                             get_identifier ("__int128_t"),
2794                                             intTI_type_node));
2795 #endif
2796   (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL, NULL_TREE,
2797                                             unsigned_intQI_type_node));
2798   (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL, NULL_TREE,
2799                                             unsigned_intHI_type_node));
2800   (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL, NULL_TREE,
2801                                             unsigned_intSI_type_node));
2802   (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL, NULL_TREE,
2803                                             unsigned_intDI_type_node));
2804 #if HOST_BITS_PER_WIDE_INT >= 64
2805   (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL,
2806                                             get_identifier ("__uint128_t"),
2807                                             unsigned_intTI_type_node));
2808 #endif
2809
2810   /* Create the widest literal types.  */
2811   widest_integer_literal_type_node
2812     = make_signed_type (HOST_BITS_PER_WIDE_INT * 2);
2813   (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL, NULL_TREE,
2814                                             widest_integer_literal_type_node));
2815
2816   widest_unsigned_literal_type_node
2817     = make_unsigned_type (HOST_BITS_PER_WIDE_INT * 2);
2818   (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL, NULL_TREE,
2819                                             widest_unsigned_literal_type_node));
2820
2821   /* `unsigned long' is the standard type for sizeof.
2822      Note that stddef.h uses `unsigned long',
2823      and this must agree, even if long and int are the same size.  */
2824   c_size_type_node =
2825     TREE_TYPE (identifier_global_value (get_identifier (SIZE_TYPE)));
2826   signed_size_type_node = c_common_signed_type (c_size_type_node);
2827   set_sizetype (c_size_type_node);
2828
2829   build_common_tree_nodes_2 (flag_short_double);
2830
2831   record_builtin_type (RID_FLOAT, NULL, float_type_node);
2832   record_builtin_type (RID_DOUBLE, NULL, double_type_node);
2833   record_builtin_type (RID_MAX, "long double", long_double_type_node);
2834
2835   (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL,
2836                                             get_identifier ("complex int"),
2837                                             complex_integer_type_node));
2838   (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL,
2839                                             get_identifier ("complex float"),
2840                                             complex_float_type_node));
2841   (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL,
2842                                             get_identifier ("complex double"),
2843                                             complex_double_type_node));
2844   (*lang_hooks.decls.pushdecl)
2845     (build_decl (TYPE_DECL, get_identifier ("complex long double"),
2846                  complex_long_double_type_node));
2847
2848   /* Types which are common to the fortran compiler and libf2c.  When
2849      changing these, you also need to be concerned with f/com.h.  */
2850
2851   if (TYPE_PRECISION (float_type_node)
2852       == TYPE_PRECISION (long_integer_type_node))
2853     {
2854       g77_integer_type_node = long_integer_type_node;
2855       g77_uinteger_type_node = long_unsigned_type_node;
2856     }
2857   else if (TYPE_PRECISION (float_type_node)
2858            == TYPE_PRECISION (integer_type_node))
2859     {
2860       g77_integer_type_node = integer_type_node;
2861       g77_uinteger_type_node = unsigned_type_node;
2862     }
2863   else
2864     g77_integer_type_node = g77_uinteger_type_node = NULL_TREE;
2865
2866   if (g77_integer_type_node != NULL_TREE)
2867     {
2868       (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL,
2869                                                 get_identifier ("__g77_integer"),
2870                                                 g77_integer_type_node));
2871       (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL,
2872                                                 get_identifier ("__g77_uinteger"),
2873                                                 g77_uinteger_type_node));
2874     }
2875
2876   if (TYPE_PRECISION (float_type_node) * 2
2877       == TYPE_PRECISION (long_integer_type_node))
2878     {
2879       g77_longint_type_node = long_integer_type_node;
2880       g77_ulongint_type_node = long_unsigned_type_node;
2881     }
2882   else if (TYPE_PRECISION (float_type_node) * 2
2883            == TYPE_PRECISION (long_long_integer_type_node))
2884     {
2885       g77_longint_type_node = long_long_integer_type_node;
2886       g77_ulongint_type_node = long_long_unsigned_type_node;
2887     }
2888   else
2889     g77_longint_type_node = g77_ulongint_type_node = NULL_TREE;
2890
2891   if (g77_longint_type_node != NULL_TREE)
2892     {
2893       (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL,
2894                                                 get_identifier ("__g77_longint"),
2895                                                 g77_longint_type_node));
2896       (*lang_hooks.decls.pushdecl) (build_decl (TYPE_DECL,
2897                                                 get_identifier ("__g77_ulongint"),
2898                                                 g77_ulongint_type_node));
2899     }
2900
2901   record_builtin_type (RID_VOID, NULL, void_type_node);
2902
2903   void_zero_node = build_int_2 (0, 0);
2904   TREE_TYPE (void_zero_node) = void_type_node;
2905
2906   void_list_node = build_void_list_node ();
2907
2908   /* Make a type to be the domain of a few array types
2909      whose domains don't really matter.
2910      200 is small enough that it always fits in size_t
2911      and large enough that it can hold most function names for the
2912      initializations of __FUNCTION__ and __PRETTY_FUNCTION__.  */
2913   array_domain_type = build_index_type (size_int (200));
2914
2915   /* Make a type for arrays of characters.
2916      With luck nothing will ever really depend on the length of this
2917      array type.  */
2918   char_array_type_node
2919     = build_array_type (char_type_node, array_domain_type);
2920
2921   /* Likewise for arrays of ints.  */
2922   int_array_type_node
2923     = build_array_type (integer_type_node, array_domain_type);
2924
2925   string_type_node = build_pointer_type (char_type_node);
2926   const_string_type_node
2927     = build_pointer_type (build_qualified_type
2928                           (char_type_node, TYPE_QUAL_CONST));
2929
2930   (*targetm.init_builtins) ();
2931
2932   /* This is special for C++ so functions can be overloaded.  */
2933   wchar_type_node = get_identifier (MODIFIED_WCHAR_TYPE);
2934   wchar_type_node = TREE_TYPE (identifier_global_value (wchar_type_node));
2935   wchar_type_size = TYPE_PRECISION (wchar_type_node);
2936   if (c_language == clk_cplusplus)
2937     {
2938       if (TREE_UNSIGNED (wchar_type_node))
2939         wchar_type_node = make_unsigned_type (wchar_type_size);
2940       else
2941         wchar_type_node = make_signed_type (wchar_type_size);
2942       record_builtin_type (RID_WCHAR, "wchar_t", wchar_type_node);
2943     }
2944   else
2945     {
2946       signed_wchar_type_node = c_common_signed_type (wchar_type_node);
2947       unsigned_wchar_type_node = c_common_unsigned_type (wchar_type_node);
2948     }
2949
2950   /* This is for wide string constants.  */
2951   wchar_array_type_node
2952     = build_array_type (wchar_type_node, array_domain_type);
2953
2954   wint_type_node =
2955     TREE_TYPE (identifier_global_value (get_identifier (WINT_TYPE)));
2956
2957   intmax_type_node =
2958     TREE_TYPE (identifier_global_value (get_identifier (INTMAX_TYPE)));
2959   uintmax_type_node =
2960     TREE_TYPE (identifier_global_value (get_identifier (UINTMAX_TYPE)));
2961
2962   default_function_type = build_function_type (integer_type_node, NULL_TREE);
2963   ptrdiff_type_node
2964     = TREE_TYPE (identifier_global_value (get_identifier (PTRDIFF_TYPE)));
2965   unsigned_ptrdiff_type_node = c_common_unsigned_type (ptrdiff_type_node);
2966
2967   (*lang_hooks.decls.pushdecl)
2968     (build_decl (TYPE_DECL, get_identifier ("__builtin_va_list"),
2969                  va_list_type_node));
2970
2971   (*lang_hooks.decls.pushdecl)
2972     (build_decl (TYPE_DECL, get_identifier ("__builtin_ptrdiff_t"),
2973                  ptrdiff_type_node));
2974
2975   (*lang_hooks.decls.pushdecl)
2976     (build_decl (TYPE_DECL, get_identifier ("__builtin_size_t"),
2977                  sizetype));
2978
2979   if (TREE_CODE (va_list_type_node) == ARRAY_TYPE)
2980     {
2981       va_list_arg_type_node = va_list_ref_type_node =
2982         build_pointer_type (TREE_TYPE (va_list_type_node));
2983     }
2984   else
2985     {
2986       va_list_arg_type_node = va_list_type_node;
2987       va_list_ref_type_node = build_reference_type (va_list_type_node);
2988     }
2989
2990 #define DEF_PRIMITIVE_TYPE(ENUM, VALUE) \
2991   builtin_types[(int) ENUM] = VALUE;
2992 #define DEF_FUNCTION_TYPE_0(ENUM, RETURN)               \
2993   builtin_types[(int) ENUM]                             \
2994     = build_function_type (builtin_types[(int) RETURN], \
2995                            void_list_node);
2996 #define DEF_FUNCTION_TYPE_1(ENUM, RETURN, ARG1)                         \
2997   builtin_types[(int) ENUM]                                             \
2998     = build_function_type (builtin_types[(int) RETURN],                 \
2999                            tree_cons (NULL_TREE,                        \
3000                                       builtin_types[(int) ARG1],        \
3001                                       void_list_node));
3002 #define DEF_FUNCTION_TYPE_2(ENUM, RETURN, ARG1, ARG2)   \
3003   builtin_types[(int) ENUM]                             \
3004     = build_function_type                               \
3005       (builtin_types[(int) RETURN],                     \
3006        tree_cons (NULL_TREE,                            \
3007                   builtin_types[(int) ARG1],            \
3008                   tree_cons (NULL_TREE,                 \
3009                              builtin_types[(int) ARG2], \
3010                              void_list_node)));
3011 #define DEF_FUNCTION_TYPE_3(ENUM, RETURN, ARG1, ARG2, ARG3)              \
3012   builtin_types[(int) ENUM]                                              \
3013     = build_function_type                                                \
3014       (builtin_types[(int) RETURN],                                      \
3015        tree_cons (NULL_TREE,                                             \
3016                   builtin_types[(int) ARG1],                             \
3017                   tree_cons (NULL_TREE,                                  \
3018                              builtin_types[(int) ARG2],                  \
3019                              tree_cons (NULL_TREE,                       \
3020                                         builtin_types[(int) ARG3],       \
3021                                         void_list_node))));
3022 #define DEF_FUNCTION_TYPE_4(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4)       \
3023   builtin_types[(int) ENUM]                                             \
3024     = build_function_type                                               \
3025       (builtin_types[(int) RETURN],                                     \
3026        tree_cons (NULL_TREE,                                            \
3027                   builtin_types[(int) ARG1],                            \
3028                   tree_cons (NULL_TREE,                                 \
3029                              builtin_types[(int) ARG2],                 \
3030                              tree_cons                                  \
3031                              (NULL_TREE,                                \
3032                               builtin_types[(int) ARG3],                \
3033                               tree_cons (NULL_TREE,                     \
3034                                          builtin_types[(int) ARG4],     \
3035                                          void_list_node)))));
3036 #define DEF_FUNCTION_TYPE_VAR_0(ENUM, RETURN)                           \
3037   builtin_types[(int) ENUM]                                             \
3038     = build_function_type (builtin_types[(int) RETURN], NULL_TREE);
3039 #define DEF_FUNCTION_TYPE_VAR_1(ENUM, RETURN, ARG1)                      \
3040    builtin_types[(int) ENUM]                                             \
3041     = build_function_type (builtin_types[(int) RETURN],                  \
3042                            tree_cons (NULL_TREE,                         \
3043                                       builtin_types[(int) ARG1],         \
3044                                       NULL_TREE));
3045
3046 #define DEF_FUNCTION_TYPE_VAR_2(ENUM, RETURN, ARG1, ARG2)       \
3047    builtin_types[(int) ENUM]                                    \
3048     = build_function_type                                       \
3049       (builtin_types[(int) RETURN],                             \
3050        tree_cons (NULL_TREE,                                    \
3051                   builtin_types[(int) ARG1],                    \
3052                   tree_cons (NULL_TREE,                         \
3053                              builtin_types[(int) ARG2],         \
3054                              NULL_TREE)));
3055 #define DEF_POINTER_TYPE(ENUM, TYPE)                    \
3056   builtin_types[(int) ENUM]                             \
3057     = build_pointer_type (builtin_types[(int) TYPE]);
3058 #include "builtin-types.def"
3059 #undef DEF_PRIMITIVE_TYPE
3060 #undef DEF_FUNCTION_TYPE_1
3061 #undef DEF_FUNCTION_TYPE_2
3062 #undef DEF_FUNCTION_TYPE_3
3063 #undef DEF_FUNCTION_TYPE_4
3064 #undef DEF_FUNCTION_TYPE_VAR_0
3065 #undef DEF_FUNCTION_TYPE_VAR_1
3066 #undef DEF_POINTER_TYPE
3067
3068   if (!c_attrs_initialized)
3069     c_init_attributes ();
3070
3071 #define DEF_BUILTIN(ENUM, NAME, CLASS, TYPE, LIBTYPE,                   \
3072                     BOTH_P, FALLBACK_P, NONANSI_P, ATTRS)               \
3073   if (NAME)                                                             \
3074     {                                                                   \
3075       tree decl;                                                        \
3076                                                                         \
3077       if (strncmp (NAME, "__builtin_", strlen ("__builtin_")) != 0)     \
3078         abort ();                                                       \
3079                                                                         \
3080       if (!BOTH_P)                                                      \
3081         decl = builtin_function (NAME, builtin_types[TYPE], ENUM,       \
3082                                  CLASS,                                 \
3083                                  (FALLBACK_P                            \
3084                                   ? (NAME + strlen ("__builtin_"))      \
3085                                   : NULL),                              \
3086                                  built_in_attributes[(int) ATTRS]);     \
3087       else                                                              \
3088         decl = builtin_function_2 (NAME,                                \
3089                                    NAME + strlen ("__builtin_"),        \
3090                                    builtin_types[TYPE],                 \
3091                                    builtin_types[LIBTYPE],              \
3092                                    ENUM,                                \
3093                                    CLASS,                               \
3094                                    FALLBACK_P,                          \
3095                                    NONANSI_P,                           \
3096                                    built_in_attributes[(int) ATTRS]);   \
3097                                                                         \
3098       built_in_decls[(int) ENUM] = decl;                                \
3099     }
3100 #include "builtins.def"
3101 #undef DEF_BUILTIN
3102
3103   main_identifier_node = get_identifier ("main");
3104 }
3105
3106 tree
3107 build_va_arg (expr, type)
3108      tree expr, type;
3109 {
3110   return build1 (VA_ARG_EXPR, type, expr);
3111 }
3112
3113
3114 /* Linked list of disabled built-in functions.  */
3115
3116 typedef struct disabled_builtin
3117 {
3118   const char *name;
3119   struct disabled_builtin *next;
3120 } disabled_builtin;
3121 static disabled_builtin *disabled_builtins = NULL;
3122
3123 static bool builtin_function_disabled_p PARAMS ((const char *));
3124
3125 /* Disable a built-in function specified by -fno-builtin-NAME.  If NAME
3126    begins with "__builtin_", give an error.  */
3127
3128 void
3129 disable_builtin_function (name)
3130      const char *name;
3131 {
3132   if (strncmp (name, "__builtin_", strlen ("__builtin_")) == 0)
3133     error ("cannot disable built-in function `%s'", name);
3134   else
3135     {
3136       disabled_builtin *new = xmalloc (sizeof (disabled_builtin));
3137       new->name = name;
3138       new->next = disabled_builtins;
3139       disabled_builtins = new;
3140     }
3141 }
3142
3143
3144 /* Return true if the built-in function NAME has been disabled, false
3145    otherwise.  */
3146
3147 static bool
3148 builtin_function_disabled_p (name)
3149      const char *name;
3150 {
3151   disabled_builtin *p;
3152   for (p = disabled_builtins; p != NULL; p = p->next)
3153     {
3154       if (strcmp (name, p->name) == 0)
3155         return true;
3156     }
3157   return false;
3158 }
3159
3160
3161 /* Possibly define a builtin function with one or two names.  BUILTIN_NAME
3162    is an __builtin_-prefixed name; NAME is the ordinary name; one or both
3163    of these may be NULL (though both being NULL is useless).
3164    BUILTIN_TYPE is the type of the __builtin_-prefixed function;
3165    TYPE is the type of the function with the ordinary name.  These
3166    may differ if the ordinary name is declared with a looser type to avoid
3167    conflicts with headers.  FUNCTION_CODE and CLASS are as for
3168    builtin_function.  If LIBRARY_NAME_P is nonzero, NAME is passed as
3169    the LIBRARY_NAME parameter to builtin_function when declaring BUILTIN_NAME.
3170    If NONANSI_P is nonzero, the name NAME is treated as a non-ANSI name;
3171    ATTRS is the tree list representing the builtin's function attributes.
3172    Returns the declaration of BUILTIN_NAME, if any, otherwise
3173    the declaration of NAME.  Does not declare NAME if flag_no_builtin,
3174    or if NONANSI_P and flag_no_nonansi_builtin.  */
3175
3176 static tree
3177 builtin_function_2 (builtin_name, name, builtin_type, type, function_code,
3178                     class, library_name_p, nonansi_p, attrs)
3179      const char *builtin_name;
3180      const char *name;
3181      tree builtin_type;
3182      tree type;
3183      int function_code;
3184      enum built_in_class class;
3185      int library_name_p;
3186      int nonansi_p;
3187      tree attrs;
3188 {
3189   tree bdecl = NULL_TREE;
3190   tree decl = NULL_TREE;
3191   if (builtin_name != 0)
3192     {
3193       bdecl = builtin_function (builtin_name, builtin_type, function_code,
3194                                 class, library_name_p ? name : NULL,
3195                                 attrs);
3196     }
3197   if (name != 0 && !flag_no_builtin && !builtin_function_disabled_p (name)
3198       && !(nonansi_p && flag_no_nonansi_builtin))
3199     {
3200       decl = builtin_function (name, type, function_code, class, NULL,
3201                                attrs);
3202       if (nonansi_p)
3203         DECL_BUILT_IN_NONANSI (decl) = 1;
3204     }
3205   return (bdecl != 0 ? bdecl : decl);
3206 }
3207 \f
3208 /* Nonzero if the type T promotes to int.  This is (nearly) the
3209    integral promotions defined in ISO C99 6.3.1.1/2.  */
3210
3211 bool
3212 c_promoting_integer_type_p (t)
3213      tree t;
3214 {
3215   switch (TREE_CODE (t))
3216     {
3217     case INTEGER_TYPE:
3218       return (TYPE_MAIN_VARIANT (t) == char_type_node
3219               || TYPE_MAIN_VARIANT (t) == signed_char_type_node
3220               || TYPE_MAIN_VARIANT (t) == unsigned_char_type_node
3221               || TYPE_MAIN_VARIANT (t) == short_integer_type_node
3222               || TYPE_MAIN_VARIANT (t) == short_unsigned_type_node
3223               || TYPE_PRECISION (t) < TYPE_PRECISION (integer_type_node));
3224
3225     case ENUMERAL_TYPE:
3226       /* ??? Technically all enumerations not larger than an int
3227          promote to an int.  But this is used along code paths
3228          that only want to notice a size change.  */
3229       return TYPE_PRECISION (t) < TYPE_PRECISION (integer_type_node);
3230
3231     case BOOLEAN_TYPE:
3232       return 1;
3233
3234     default:
3235       return 0;
3236     }
3237 }
3238
3239 /* Return 1 if PARMS specifies a fixed number of parameters
3240    and none of their types is affected by default promotions.  */
3241
3242 int
3243 self_promoting_args_p (parms)
3244      tree parms;
3245 {
3246   tree t;
3247   for (t = parms; t; t = TREE_CHAIN (t))
3248     {
3249       tree type = TREE_VALUE (t);
3250
3251       if (TREE_CHAIN (t) == 0 && type != void_type_node)
3252         return 0;
3253
3254       if (type == 0)
3255         return 0;
3256
3257       if (TYPE_MAIN_VARIANT (type) == float_type_node)
3258         return 0;
3259
3260       if (c_promoting_integer_type_p (type))
3261         return 0;
3262     }
3263   return 1;
3264 }
3265
3266 /* Recursively examines the array elements of TYPE, until a non-array
3267    element type is found.  */
3268
3269 tree
3270 strip_array_types (type)
3271      tree type;
3272 {
3273   while (TREE_CODE (type) == ARRAY_TYPE)
3274     type = TREE_TYPE (type);
3275
3276   return type;
3277 }
3278
3279 static tree expand_unordered_cmp PARAMS ((tree, tree, enum tree_code,
3280                                           enum tree_code));
3281
3282 /* Expand a call to an unordered comparison function such as
3283    __builtin_isgreater().  FUNCTION is the function's declaration and
3284    PARAMS a list of the values passed.  For __builtin_isunordered(),
3285    UNORDERED_CODE is UNORDERED_EXPR and ORDERED_CODE is NOP_EXPR.  In
3286    other cases, UNORDERED_CODE and ORDERED_CODE are comparison codes
3287    that give the opposite of the desired result.  UNORDERED_CODE is
3288    used for modes that can hold NaNs and ORDERED_CODE is used for the
3289    rest.  */
3290
3291 static tree
3292 expand_unordered_cmp (function, params, unordered_code, ordered_code)
3293      tree function, params;
3294      enum tree_code unordered_code, ordered_code;
3295 {
3296   tree arg0, arg1, type;
3297   enum tree_code code0, code1;
3298
3299   /* Check that we have exactly two arguments.  */
3300   if (params == 0 || TREE_CHAIN (params) == 0)
3301     {
3302       error ("too few arguments to function `%s'",
3303              IDENTIFIER_POINTER (DECL_NAME (function)));
3304       return error_mark_node;
3305     }
3306   else if (TREE_CHAIN (TREE_CHAIN (params)) != 0)
3307     {
3308       error ("too many arguments to function `%s'",
3309              IDENTIFIER_POINTER (DECL_NAME (function)));
3310       return error_mark_node;
3311     }
3312
3313   arg0 = TREE_VALUE (params);
3314   arg1 = TREE_VALUE (TREE_CHAIN (params));
3315
3316   code0 = TREE_CODE (TREE_TYPE (arg0));
3317   code1 = TREE_CODE (TREE_TYPE (arg1));
3318
3319   /* Make sure that the arguments have a common type of REAL.  */
3320   type = 0;
3321   if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3322       && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3323     type = common_type (TREE_TYPE (arg0), TREE_TYPE (arg1));
3324
3325   if (type == 0 || TREE_CODE (type) != REAL_TYPE)
3326     {
3327       error ("non-floating-point argument to function `%s'",
3328              IDENTIFIER_POINTER (DECL_NAME (function)));
3329       return error_mark_node;
3330     }
3331
3332   if (unordered_code == UNORDERED_EXPR)
3333     {
3334       if (MODE_HAS_NANS (TYPE_MODE (type)))
3335         return build_binary_op (unordered_code,
3336                                 convert (type, arg0),
3337                                 convert (type, arg1),
3338                                 0);
3339       else
3340         return integer_zero_node;
3341     }
3342
3343   return build_unary_op (TRUTH_NOT_EXPR,
3344                          build_binary_op (MODE_HAS_NANS (TYPE_MODE (type))
3345                                           ? unordered_code
3346                                           : ordered_code,
3347                                           convert (type, arg0),
3348                                           convert (type, arg1),
3349                                           0),
3350                          0);
3351 }
3352
3353
3354 /* Recognize certain built-in functions so we can make tree-codes
3355    other than CALL_EXPR.  We do this when it enables fold-const.c
3356    to do something useful.  */
3357 /* ??? By rights this should go in builtins.c, but only C and C++
3358    implement build_{binary,unary}_op.  Not exactly sure what bits
3359    of functionality are actually needed from those functions, or
3360    where the similar functionality exists in the other front ends.  */
3361
3362 tree
3363 expand_tree_builtin (function, params, coerced_params)
3364      tree function, params, coerced_params;
3365 {
3366   if (DECL_BUILT_IN_CLASS (function) != BUILT_IN_NORMAL)
3367     return NULL_TREE;
3368
3369   switch (DECL_FUNCTION_CODE (function))
3370     {
3371     case BUILT_IN_ABS:
3372     case BUILT_IN_LABS:
3373     case BUILT_IN_LLABS:
3374     case BUILT_IN_IMAXABS:
3375     case BUILT_IN_FABS:
3376     case BUILT_IN_FABSL:
3377     case BUILT_IN_FABSF:
3378       if (coerced_params == 0)
3379         return integer_zero_node;
3380       return build_unary_op (ABS_EXPR, TREE_VALUE (coerced_params), 0);
3381
3382     case BUILT_IN_CONJ:
3383     case BUILT_IN_CONJF:
3384     case BUILT_IN_CONJL:
3385       if (coerced_params == 0)
3386         return integer_zero_node;
3387       return build_unary_op (CONJ_EXPR, TREE_VALUE (coerced_params), 0);
3388
3389     case BUILT_IN_CREAL:
3390     case BUILT_IN_CREALF:
3391     case BUILT_IN_CREALL:
3392       if (coerced_params == 0)
3393         return integer_zero_node;
3394       return build_unary_op (REALPART_EXPR, TREE_VALUE (coerced_params), 0);
3395
3396     case BUILT_IN_CIMAG:
3397     case BUILT_IN_CIMAGF:
3398     case BUILT_IN_CIMAGL:
3399       if (coerced_params == 0)
3400         return integer_zero_node;
3401       return build_unary_op (IMAGPART_EXPR, TREE_VALUE (coerced_params), 0);
3402
3403     case BUILT_IN_ISGREATER:
3404       return expand_unordered_cmp (function, params, UNLE_EXPR, LE_EXPR);
3405
3406     case BUILT_IN_ISGREATEREQUAL:
3407       return expand_unordered_cmp (function, params, UNLT_EXPR, LT_EXPR);
3408
3409     case BUILT_IN_ISLESS:
3410       return expand_unordered_cmp (function, params, UNGE_EXPR, GE_EXPR);
3411
3412     case BUILT_IN_ISLESSEQUAL:
3413       return expand_unordered_cmp (function, params, UNGT_EXPR, GT_EXPR);
3414
3415     case BUILT_IN_ISLESSGREATER:
3416       return expand_unordered_cmp (function, params, UNEQ_EXPR, EQ_EXPR);
3417
3418     case BUILT_IN_ISUNORDERED:
3419       return expand_unordered_cmp (function, params, UNORDERED_EXPR, NOP_EXPR);
3420
3421     default:
3422       break;
3423     }
3424
3425   return NULL_TREE;
3426 }
3427
3428 /* Returns non-zero if CODE is the code for a statement.  */
3429
3430 int
3431 statement_code_p (code)
3432      enum tree_code code;
3433 {
3434   switch (code)
3435     {
3436     case CLEANUP_STMT:
3437     case EXPR_STMT:
3438     case COMPOUND_STMT:
3439     case DECL_STMT:
3440     case IF_STMT:
3441     case FOR_STMT:
3442     case WHILE_STMT:
3443     case DO_STMT:
3444     case RETURN_STMT:
3445     case BREAK_STMT:
3446     case CONTINUE_STMT:
3447     case SCOPE_STMT:
3448     case SWITCH_STMT:
3449     case GOTO_STMT:
3450     case LABEL_STMT:
3451     case ASM_STMT:
3452     case FILE_STMT:
3453     case CASE_LABEL:
3454       return 1;
3455
3456     default:
3457       if (lang_statement_code_p)
3458         return (*lang_statement_code_p) (code);
3459       return 0;
3460     }
3461 }
3462
3463 /* Walk the statement tree, rooted at *tp.  Apply FUNC to all the
3464    sub-trees of *TP in a pre-order traversal.  FUNC is called with the
3465    DATA and the address of each sub-tree.  If FUNC returns a non-NULL
3466    value, the traversal is aborted, and the value returned by FUNC is
3467    returned.  If FUNC sets WALK_SUBTREES to zero, then the subtrees of
3468    the node being visited are not walked.
3469
3470    We don't need a without_duplicates variant of this one because the
3471    statement tree is a tree, not a graph.  */
3472
3473 tree
3474 walk_stmt_tree (tp, func, data)
3475      tree *tp;
3476      walk_tree_fn func;
3477      void *data;
3478 {
3479   enum tree_code code;
3480   int walk_subtrees;
3481   tree result;
3482   int i, len;
3483
3484 #define WALK_SUBTREE(NODE)                              \
3485   do                                                    \
3486     {                                                   \
3487       result = walk_stmt_tree (&(NODE), func, data);    \
3488       if (result)                                       \
3489         return result;                                  \
3490     }                                                   \
3491   while (0)
3492
3493   /* Skip empty subtrees.  */
3494   if (!*tp)
3495     return NULL_TREE;
3496
3497   /* Skip subtrees below non-statement nodes.  */
3498   if (!statement_code_p (TREE_CODE (*tp)))
3499     return NULL_TREE;
3500
3501   /* Call the function.  */
3502   walk_subtrees = 1;
3503   result = (*func) (tp, &walk_subtrees, data);
3504
3505   /* If we found something, return it.  */
3506   if (result)
3507     return result;
3508
3509   /* FUNC may have modified the tree, recheck that we're looking at a
3510      statement node.  */
3511   code = TREE_CODE (*tp);
3512   if (!statement_code_p (code))
3513     return NULL_TREE;
3514
3515   /* Visit the subtrees unless FUNC decided that there was nothing
3516      interesting below this point in the tree.  */
3517   if (walk_subtrees)
3518     {
3519       /* Walk over all the sub-trees of this operand.  Statement nodes
3520          never contain RTL, and we needn't worry about TARGET_EXPRs.  */
3521       len = TREE_CODE_LENGTH (code);
3522
3523       /* Go through the subtrees.  We need to do this in forward order so
3524          that the scope of a FOR_EXPR is handled properly.  */
3525       for (i = 0; i < len; ++i)
3526         WALK_SUBTREE (TREE_OPERAND (*tp, i));
3527     }
3528
3529   /* Finally visit the chain.  This can be tail-recursion optimized if
3530      we write it this way.  */
3531   return walk_stmt_tree (&TREE_CHAIN (*tp), func, data);
3532
3533 #undef WALK_SUBTREE
3534 }
3535
3536 /* Used to compare case labels.  K1 and K2 are actually tree nodes
3537    representing case labels, or NULL_TREE for a `default' label.
3538    Returns -1 if K1 is ordered before K2, -1 if K1 is ordered after
3539    K2, and 0 if K1 and K2 are equal.  */
3540
3541 int
3542 case_compare (k1, k2)
3543      splay_tree_key k1;
3544      splay_tree_key k2;
3545 {
3546   /* Consider a NULL key (such as arises with a `default' label) to be
3547      smaller than anything else.  */
3548   if (!k1)
3549     return k2 ? -1 : 0;
3550   else if (!k2)
3551     return k1 ? 1 : 0;
3552
3553   return tree_int_cst_compare ((tree) k1, (tree) k2);
3554 }
3555
3556 /* Process a case label for the range LOW_VALUE ... HIGH_VALUE.  If
3557    LOW_VALUE and HIGH_VALUE are both NULL_TREE then this case label is
3558    actually a `default' label.  If only HIGH_VALUE is NULL_TREE, then
3559    case label was declared using the usual C/C++ syntax, rather than
3560    the GNU case range extension.  CASES is a tree containing all the
3561    case ranges processed so far; COND is the condition for the
3562    switch-statement itself.  Returns the CASE_LABEL created, or
3563    ERROR_MARK_NODE if no CASE_LABEL is created.  */
3564
3565 tree
3566 c_add_case_label (cases, cond, low_value, high_value)
3567      splay_tree cases;
3568      tree cond;
3569      tree low_value;
3570      tree high_value;
3571 {
3572   tree type;
3573   tree label;
3574   tree case_label;
3575   splay_tree_node node;
3576
3577   /* Create the LABEL_DECL itself.  */
3578   label = build_decl (LABEL_DECL, NULL_TREE, NULL_TREE);
3579   DECL_CONTEXT (label) = current_function_decl;
3580
3581   /* If there was an error processing the switch condition, bail now
3582      before we get more confused.  */
3583   if (!cond || cond == error_mark_node)
3584     {
3585       /* Add a label anyhow so that the back-end doesn't think that
3586          the beginning of the switch is unreachable.  */
3587       if (!cases->root)
3588         add_stmt (build_case_label (NULL_TREE, NULL_TREE, label));
3589       return error_mark_node;
3590     }
3591
3592   if ((low_value && TREE_TYPE (low_value)
3593        && POINTER_TYPE_P (TREE_TYPE (low_value)))
3594       || (high_value && TREE_TYPE (high_value)
3595           && POINTER_TYPE_P (TREE_TYPE (high_value))))
3596     error ("pointers are not permitted as case values");
3597
3598   /* Case ranges are a GNU extension.  */
3599   if (high_value && pedantic)
3600     {
3601       if (c_language == clk_cplusplus)
3602         pedwarn ("ISO C++ forbids range expressions in switch statements");
3603       else
3604         pedwarn ("ISO C forbids range expressions in switch statements");
3605     }
3606
3607   type = TREE_TYPE (cond);
3608   if (low_value)
3609     {
3610       low_value = check_case_value (low_value);
3611       low_value = convert_and_check (type, low_value);
3612     }
3613   if (high_value)
3614     {
3615       high_value = check_case_value (high_value);
3616       high_value = convert_and_check (type, high_value);
3617     }
3618
3619   /* If an error has occurred, bail out now.  */
3620   if (low_value == error_mark_node || high_value == error_mark_node)
3621     {
3622       if (!cases->root)
3623         add_stmt (build_case_label (NULL_TREE, NULL_TREE, label));
3624       return error_mark_node;
3625     }
3626
3627   /* If the LOW_VALUE and HIGH_VALUE are the same, then this isn't
3628      really a case range, even though it was written that way.  Remove
3629      the HIGH_VALUE to simplify later processing.  */
3630   if (tree_int_cst_equal (low_value, high_value))
3631     high_value = NULL_TREE;
3632   if (low_value && high_value
3633       && !tree_int_cst_lt (low_value, high_value))
3634     warning ("empty range specified");
3635
3636   /* Look up the LOW_VALUE in the table of case labels we already
3637      have.  */
3638   node = splay_tree_lookup (cases, (splay_tree_key) low_value);
3639   /* If there was not an exact match, check for overlapping ranges.
3640      There's no need to do this if there's no LOW_VALUE or HIGH_VALUE;
3641      that's a `default' label and the only overlap is an exact match.  */
3642   if (!node && (low_value || high_value))
3643     {
3644       splay_tree_node low_bound;
3645       splay_tree_node high_bound;
3646
3647       /* Even though there wasn't an exact match, there might be an
3648          overlap between this case range and another case range.
3649          Since we've (inductively) not allowed any overlapping case
3650          ranges, we simply need to find the greatest low case label
3651          that is smaller that LOW_VALUE, and the smallest low case
3652          label that is greater than LOW_VALUE.  If there is an overlap
3653          it will occur in one of these two ranges.  */
3654       low_bound = splay_tree_predecessor (cases,
3655                                           (splay_tree_key) low_value);
3656       high_bound = splay_tree_successor (cases,
3657                                          (splay_tree_key) low_value);
3658
3659       /* Check to see if the LOW_BOUND overlaps.  It is smaller than
3660          the LOW_VALUE, so there is no need to check unless the
3661          LOW_BOUND is in fact itself a case range.  */
3662       if (low_bound
3663           && CASE_HIGH ((tree) low_bound->value)
3664           && tree_int_cst_compare (CASE_HIGH ((tree) low_bound->value),
3665                                     low_value) >= 0)
3666         node = low_bound;
3667       /* Check to see if the HIGH_BOUND overlaps.  The low end of that
3668          range is bigger than the low end of the current range, so we
3669          are only interested if the current range is a real range, and
3670          not an ordinary case label.  */
3671       else if (high_bound
3672                && high_value
3673                && (tree_int_cst_compare ((tree) high_bound->key,
3674                                          high_value)
3675                    <= 0))
3676         node = high_bound;
3677     }
3678   /* If there was an overlap, issue an error.  */
3679   if (node)
3680     {
3681       tree duplicate = CASE_LABEL_DECL ((tree) node->value);
3682
3683       if (high_value)
3684         {
3685           error ("duplicate (or overlapping) case value");
3686           error_with_decl (duplicate,
3687                            "this is the first entry overlapping that value");
3688         }
3689       else if (low_value)
3690         {
3691           error ("duplicate case value") ;
3692           error_with_decl (duplicate, "previously used here");
3693         }
3694       else
3695         {
3696           error ("multiple default labels in one switch");
3697           error_with_decl (duplicate, "this is the first default label");
3698         }
3699       if (!cases->root)
3700         add_stmt (build_case_label (NULL_TREE, NULL_TREE, label));
3701     }
3702
3703   /* Add a CASE_LABEL to the statement-tree.  */
3704   case_label = add_stmt (build_case_label (low_value, high_value, label));
3705   /* Register this case label in the splay tree.  */
3706   splay_tree_insert (cases,
3707                      (splay_tree_key) low_value,
3708                      (splay_tree_value) case_label);
3709
3710   return case_label;
3711 }
3712
3713 /* Finish an expression taking the address of LABEL.  Returns an
3714    expression for the address.  */
3715
3716 tree
3717 finish_label_address_expr (label)
3718      tree label;
3719 {
3720   tree result;
3721
3722   if (pedantic)
3723     {
3724       if (c_language == clk_cplusplus)
3725         pedwarn ("ISO C++ forbids taking the address of a label");
3726       else
3727         pedwarn ("ISO C forbids taking the address of a label");
3728     }
3729
3730   label = lookup_label (label);
3731   if (label == NULL_TREE)
3732     result = null_pointer_node;
3733   else
3734     {
3735       TREE_USED (label) = 1;
3736       result = build1 (ADDR_EXPR, ptr_type_node, label);
3737       TREE_CONSTANT (result) = 1;
3738       /* The current function in not necessarily uninlinable.
3739          Computed gotos are incompatible with inlining, but the value
3740          here could be used only in a diagnostic, for example.  */
3741     }
3742
3743   return result;
3744 }
3745
3746 /* Hook used by expand_expr to expand language-specific tree codes.  */
3747
3748 rtx
3749 c_expand_expr (exp, target, tmode, modifier)
3750      tree exp;
3751      rtx target;
3752      enum machine_mode tmode;
3753      int modifier;  /* Actually enum_modifier.  */
3754 {
3755   switch (TREE_CODE (exp))
3756     {
3757     case STMT_EXPR:
3758       {
3759         tree rtl_expr;
3760         rtx result;
3761         bool preserve_result = false;
3762
3763         /* Since expand_expr_stmt calls free_temp_slots after every
3764            expression statement, we must call push_temp_slots here.
3765            Otherwise, any temporaries in use now would be considered
3766            out-of-scope after the first EXPR_STMT from within the
3767            STMT_EXPR.  */
3768         push_temp_slots ();
3769         rtl_expr = expand_start_stmt_expr (!STMT_EXPR_NO_SCOPE (exp));
3770
3771         /* If we want the result of this expression, find the last
3772            EXPR_STMT in the COMPOUND_STMT and mark it as addressable.  */
3773         if (target != const0_rtx
3774             && TREE_CODE (STMT_EXPR_STMT (exp)) == COMPOUND_STMT
3775             && TREE_CODE (COMPOUND_BODY (STMT_EXPR_STMT (exp))) == SCOPE_STMT)
3776           {
3777             tree expr = COMPOUND_BODY (STMT_EXPR_STMT (exp));
3778             tree last = TREE_CHAIN (expr);
3779
3780             while (TREE_CHAIN (last))
3781               {
3782                 expr = last;
3783                 last = TREE_CHAIN (last);
3784               }
3785
3786             if (TREE_CODE (last) == SCOPE_STMT
3787                 && TREE_CODE (expr) == EXPR_STMT)
3788               {
3789                 TREE_ADDRESSABLE (expr) = 1;
3790                 preserve_result = true;
3791               }
3792           }
3793
3794         expand_stmt (STMT_EXPR_STMT (exp));
3795         expand_end_stmt_expr (rtl_expr);
3796
3797         result = expand_expr (rtl_expr, target, tmode, modifier);
3798         if (preserve_result && GET_CODE (result) == MEM)
3799           {
3800             if (GET_MODE (result) != BLKmode)
3801               result = copy_to_reg (result);
3802             else
3803               preserve_temp_slots (result);
3804           }
3805
3806         /* If the statment-expression does not have a scope, then the
3807            new temporaries we created within it must live beyond the
3808            statement-expression.  */
3809         if (STMT_EXPR_NO_SCOPE (exp))
3810           preserve_temp_slots (NULL_RTX);
3811
3812         pop_temp_slots ();
3813         return result;
3814       }
3815       break;
3816
3817     case CALL_EXPR:
3818       {
3819         if (TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR
3820             && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
3821                 == FUNCTION_DECL)
3822             && DECL_BUILT_IN (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
3823             && (DECL_BUILT_IN_CLASS (TREE_OPERAND (TREE_OPERAND (exp, 0), 0))
3824                 == BUILT_IN_FRONTEND))
3825           return c_expand_builtin (exp, target, tmode, modifier);
3826         else
3827           abort ();
3828       }
3829       break;
3830
3831     case COMPOUND_LITERAL_EXPR:
3832       {
3833         /* Initialize the anonymous variable declared in the compound
3834            literal, then return the variable.  */
3835         tree decl = COMPOUND_LITERAL_EXPR_DECL (exp);
3836         emit_local_var (decl);
3837         return expand_expr (decl, target, tmode, modifier);
3838       }
3839
3840     default:
3841       abort ();
3842     }
3843
3844   abort ();
3845   return NULL;
3846 }
3847
3848 /* Hook used by safe_from_p to handle language-specific tree codes.  */
3849
3850 int
3851 c_safe_from_p (target, exp)
3852      rtx target;
3853      tree exp;
3854 {
3855   /* We can see statements here when processing the body of a
3856      statement-expression.  For a declaration statement declaring a
3857      variable, look at the variable's initializer.  */
3858   if (TREE_CODE (exp) == DECL_STMT)
3859     {
3860       tree decl = DECL_STMT_DECL (exp);
3861
3862       if (TREE_CODE (decl) == VAR_DECL
3863           && DECL_INITIAL (decl)
3864           && !safe_from_p (target, DECL_INITIAL (decl), /*top_p=*/0))
3865         return 0;
3866     }
3867
3868   /* For any statement, we must follow the statement-chain.  */
3869   if (statement_code_p (TREE_CODE (exp)) && TREE_CHAIN (exp))
3870     return safe_from_p (target, TREE_CHAIN (exp), /*top_p=*/0);
3871
3872   /* Assume everything else is safe.  */
3873   return 1;
3874 }
3875
3876 /* Hook used by unsafe_for_reeval to handle language-specific tree codes.  */
3877
3878 int
3879 c_common_unsafe_for_reeval (exp)
3880      tree exp;
3881 {
3882   /* Statement expressions may not be reevaluated, likewise compound
3883      literals.  */
3884   if (TREE_CODE (exp) == STMT_EXPR
3885       || TREE_CODE (exp) == COMPOUND_LITERAL_EXPR)
3886     return 2;
3887
3888   /* Walk all other expressions.  */
3889   return -1;
3890 }
3891
3892 /* Hook used by staticp to handle language-specific tree codes.  */
3893
3894 int
3895 c_staticp (exp)
3896      tree exp;
3897 {
3898   if (TREE_CODE (exp) == COMPOUND_LITERAL_EXPR
3899       && TREE_STATIC (COMPOUND_LITERAL_EXPR_DECL (exp)))
3900     return 1;
3901   return 0;
3902 }
3903
3904 #define CALLED_AS_BUILT_IN(NODE) \
3905    (!strncmp (IDENTIFIER_POINTER (DECL_NAME (NODE)), "__builtin_", 10))
3906
3907 static rtx
3908 c_expand_builtin (exp, target, tmode, modifier)
3909      tree exp;
3910      rtx target;
3911      enum machine_mode tmode;
3912      enum expand_modifier modifier;
3913 {
3914   tree type = TREE_TYPE (exp);
3915   tree fndecl = TREE_OPERAND (TREE_OPERAND (exp, 0), 0);
3916   tree arglist = TREE_OPERAND (exp, 1);
3917   enum built_in_function fcode = DECL_FUNCTION_CODE (fndecl);
3918   enum tree_code code = TREE_CODE (exp);
3919   const int ignore = (target == const0_rtx
3920                       || ((code == NON_LVALUE_EXPR || code == NOP_EXPR
3921                            || code == CONVERT_EXPR || code == REFERENCE_EXPR
3922                            || code == COND_EXPR)
3923                           && TREE_CODE (type) == VOID_TYPE));
3924
3925   if (! optimize && ! CALLED_AS_BUILT_IN (fndecl))
3926     return expand_call (exp, target, ignore);
3927
3928   switch (fcode)
3929     {
3930     case BUILT_IN_PRINTF:
3931       target = c_expand_builtin_printf (arglist, target, tmode,
3932                                         modifier, ignore, /*unlocked=*/ 0);
3933       if (target)
3934         return target;
3935       break;
3936
3937     case BUILT_IN_PRINTF_UNLOCKED:
3938       target = c_expand_builtin_printf (arglist, target, tmode,
3939                                         modifier, ignore, /*unlocked=*/ 1);
3940       if (target)
3941         return target;
3942       break;
3943
3944     case BUILT_IN_FPRINTF:
3945       target = c_expand_builtin_fprintf (arglist, target, tmode,
3946                                          modifier, ignore, /*unlocked=*/ 0);
3947       if (target)
3948         return target;
3949       break;
3950
3951     case BUILT_IN_FPRINTF_UNLOCKED:
3952       target = c_expand_builtin_fprintf (arglist, target, tmode,
3953                                          modifier, ignore, /*unlocked=*/ 1);
3954       if (target)
3955         return target;
3956       break;
3957
3958     default:                    /* just do library call, if unknown builtin */
3959       error ("built-in function `%s' not currently supported",
3960              IDENTIFIER_POINTER (DECL_NAME (fndecl)));
3961     }
3962
3963   /* The switch statement above can drop through to cause the function
3964      to be called normally.  */
3965   return expand_call (exp, target, ignore);
3966 }
3967
3968 /* Check an arglist to *printf for problems.  The arglist should start
3969    at the format specifier, with the remaining arguments immediately
3970    following it.  */
3971 static int
3972 is_valid_printf_arglist (arglist)
3973      tree arglist;
3974 {
3975   /* Save this value so we can restore it later.  */
3976   const int SAVE_pedantic = pedantic;
3977   int diagnostic_occurred = 0;
3978   tree attrs;
3979
3980   /* Set this to a known value so the user setting won't affect code
3981      generation.  */
3982   pedantic = 1;
3983   /* Check to make sure there are no format specifier errors.  */
3984   attrs = tree_cons (get_identifier ("format"),
3985                      tree_cons (NULL_TREE,
3986                                 get_identifier ("printf"),
3987                                 tree_cons (NULL_TREE,
3988                                            integer_one_node,
3989                                            tree_cons (NULL_TREE,
3990                                                       build_int_2 (2, 0),
3991                                                       NULL_TREE))),
3992                      NULL_TREE);
3993   check_function_format (&diagnostic_occurred, attrs, arglist);
3994
3995   /* Restore the value of `pedantic'.  */
3996   pedantic = SAVE_pedantic;
3997
3998   /* If calling `check_function_format_ptr' produces a warning, we
3999      return false, otherwise we return true.  */
4000   return ! diagnostic_occurred;
4001 }
4002
4003 /* If the arguments passed to printf are suitable for optimizations,
4004    we attempt to transform the call.  */
4005 static rtx
4006 c_expand_builtin_printf (arglist, target, tmode, modifier, ignore, unlocked)
4007      tree arglist;
4008      rtx target;
4009      enum machine_mode tmode;
4010      enum expand_modifier modifier;
4011      int ignore;
4012      int unlocked;
4013 {
4014   tree fn_putchar = unlocked ?
4015     built_in_decls[BUILT_IN_PUTCHAR_UNLOCKED] : built_in_decls[BUILT_IN_PUTCHAR];
4016   tree fn_puts = unlocked ?
4017     built_in_decls[BUILT_IN_PUTS_UNLOCKED] : built_in_decls[BUILT_IN_PUTS];
4018   tree fn, format_arg, stripped_string;
4019
4020   /* If the return value is used, or the replacement _DECL isn't
4021      initialized, don't do the transformation.  */
4022   if (!ignore || !fn_putchar || !fn_puts)
4023     return 0;
4024
4025   /* Verify the required arguments in the original call.  */
4026   if (arglist == 0
4027       || (TREE_CODE (TREE_TYPE (TREE_VALUE (arglist))) != POINTER_TYPE))
4028     return 0;
4029
4030   /* Check the specifier vs. the parameters.  */
4031   if (!is_valid_printf_arglist (arglist))
4032     return 0;
4033
4034   format_arg = TREE_VALUE (arglist);
4035   stripped_string = format_arg;
4036   STRIP_NOPS (stripped_string);
4037   if (stripped_string && TREE_CODE (stripped_string) == ADDR_EXPR)
4038     stripped_string = TREE_OPERAND (stripped_string, 0);
4039
4040   /* If the format specifier isn't a STRING_CST, punt.  */
4041   if (TREE_CODE (stripped_string) != STRING_CST)
4042     return 0;
4043
4044   /* OK!  We can attempt optimization.  */
4045
4046   /* If the format specifier was "%s\n", call __builtin_puts(arg2).  */
4047   if (strcmp (TREE_STRING_POINTER (stripped_string), "%s\n") == 0)
4048     {
4049       arglist = TREE_CHAIN (arglist);
4050       fn = fn_puts;
4051     }
4052   /* If the format specifier was "%c", call __builtin_putchar (arg2).  */
4053   else if (strcmp (TREE_STRING_POINTER (stripped_string), "%c") == 0)
4054     {
4055       arglist = TREE_CHAIN (arglist);
4056       fn = fn_putchar;
4057     }
4058   else
4059     {
4060       /* We can't handle anything else with % args or %% ... yet.  */
4061       if (strchr (TREE_STRING_POINTER (stripped_string), '%'))
4062         return 0;
4063
4064       /* If the resulting constant string has a length of 1, call
4065          putchar.  Note, TREE_STRING_LENGTH includes the terminating
4066          NULL in its count.  */
4067       if (TREE_STRING_LENGTH (stripped_string) == 2)
4068         {
4069           /* Given printf("c"), (where c is any one character,)
4070              convert "c"[0] to an int and pass that to the replacement
4071              function.  */
4072           arglist = build_int_2 (TREE_STRING_POINTER (stripped_string)[0], 0);
4073           arglist = build_tree_list (NULL_TREE, arglist);
4074
4075           fn = fn_putchar;
4076         }
4077       /* If the resulting constant was "string\n", call
4078          __builtin_puts("string").  Ensure "string" has at least one
4079          character besides the trailing \n.  Note, TREE_STRING_LENGTH
4080          includes the terminating NULL in its count.  */
4081       else if (TREE_STRING_LENGTH (stripped_string) > 2
4082                && TREE_STRING_POINTER (stripped_string)
4083                [TREE_STRING_LENGTH (stripped_string) - 2] == '\n')
4084         {
4085           /* Create a NULL-terminated string that's one char shorter
4086              than the original, stripping off the trailing '\n'.  */
4087           const int newlen = TREE_STRING_LENGTH (stripped_string) - 1;
4088           char *newstr = (char *) alloca (newlen);
4089           memcpy (newstr, TREE_STRING_POINTER (stripped_string), newlen - 1);
4090           newstr[newlen - 1] = 0;
4091
4092           arglist = fix_string_type (build_string (newlen, newstr));
4093           arglist = build_tree_list (NULL_TREE, arglist);
4094           fn = fn_puts;
4095         }
4096       else
4097         /* We'd like to arrange to call fputs(string) here, but we
4098            need stdout and don't have a way to get it ... yet.  */
4099         return 0;
4100     }
4101
4102   return expand_expr (build_function_call (fn, arglist),
4103                       (ignore ? const0_rtx : target),
4104                       tmode, modifier);
4105 }
4106
4107 /* If the arguments passed to fprintf are suitable for optimizations,
4108    we attempt to transform the call.  */
4109 static rtx
4110 c_expand_builtin_fprintf (arglist, target, tmode, modifier, ignore, unlocked)
4111      tree arglist;
4112      rtx target;
4113      enum machine_mode tmode;
4114      enum expand_modifier modifier;
4115      int ignore;
4116      int unlocked;
4117 {
4118   tree fn_fputc = unlocked ?
4119     built_in_decls[BUILT_IN_FPUTC_UNLOCKED] : built_in_decls[BUILT_IN_FPUTC];
4120   tree fn_fputs = unlocked ?
4121     built_in_decls[BUILT_IN_FPUTS_UNLOCKED] : built_in_decls[BUILT_IN_FPUTS];
4122   tree fn, format_arg, stripped_string;
4123
4124   /* If the return value is used, or the replacement _DECL isn't
4125      initialized, don't do the transformation.  */
4126   if (!ignore || !fn_fputc || !fn_fputs)
4127     return 0;
4128
4129   /* Verify the required arguments in the original call.  */
4130   if (arglist == 0
4131       || (TREE_CODE (TREE_TYPE (TREE_VALUE (arglist))) != POINTER_TYPE)
4132       || (TREE_CHAIN (arglist) == 0)
4133       || (TREE_CODE (TREE_TYPE (TREE_VALUE (TREE_CHAIN (arglist)))) !=
4134           POINTER_TYPE))
4135     return 0;
4136
4137   /* Check the specifier vs. the parameters.  */
4138   if (!is_valid_printf_arglist (TREE_CHAIN (arglist)))
4139     return 0;
4140
4141   format_arg = TREE_VALUE (TREE_CHAIN (arglist));
4142   stripped_string = format_arg;
4143   STRIP_NOPS (stripped_string);
4144   if (stripped_string && TREE_CODE (stripped_string) == ADDR_EXPR)
4145     stripped_string = TREE_OPERAND (stripped_string, 0);
4146
4147   /* If the format specifier isn't a STRING_CST, punt.  */
4148   if (TREE_CODE (stripped_string) != STRING_CST)
4149     return 0;
4150
4151   /* OK!  We can attempt optimization.  */
4152
4153   /* If the format specifier was "%s", call __builtin_fputs(arg3, arg1).  */
4154   if (strcmp (TREE_STRING_POINTER (stripped_string), "%s") == 0)
4155     {
4156       tree newarglist = build_tree_list (NULL_TREE, TREE_VALUE (arglist));
4157       arglist = tree_cons (NULL_TREE,
4158                            TREE_VALUE (TREE_CHAIN (TREE_CHAIN (arglist))),
4159                            newarglist);
4160       fn = fn_fputs;
4161     }
4162   /* If the format specifier was "%c", call __builtin_fputc (arg3, arg1).  */
4163   else if (strcmp (TREE_STRING_POINTER (stripped_string), "%c") == 0)
4164     {
4165       tree newarglist = build_tree_list (NULL_TREE, TREE_VALUE (arglist));
4166       arglist = tree_cons (NULL_TREE,
4167                            TREE_VALUE (TREE_CHAIN (TREE_CHAIN (arglist))),
4168                            newarglist);
4169       fn = fn_fputc;
4170     }
4171   else
4172     {
4173       /* We can't handle anything else with % args or %% ... yet.  */
4174       if (strchr (TREE_STRING_POINTER (stripped_string), '%'))
4175         return 0;
4176
4177       /* When "string" doesn't contain %, replace all cases of
4178          fprintf(stream,string) with fputs(string,stream).  The fputs
4179          builtin will take take of special cases like length==1.  */
4180       arglist = tree_cons (NULL_TREE, TREE_VALUE (TREE_CHAIN (arglist)),
4181                            build_tree_list (NULL_TREE, TREE_VALUE (arglist)));
4182       fn = fn_fputs;
4183     }
4184
4185   return expand_expr (build_function_call (fn, arglist),
4186                       (ignore ? const0_rtx : target),
4187                       tmode, modifier);
4188 }
4189 \f
4190
4191 /* Given a boolean expression ARG, return a tree representing an increment
4192    or decrement (as indicated by CODE) of ARG.  The front end must check for
4193    invalid cases (e.g., decrement in C++).  */
4194 tree
4195 boolean_increment (code, arg)
4196      enum tree_code code;
4197      tree arg;
4198 {
4199   tree val;
4200   tree true_res = (c_language == clk_cplusplus
4201                    ? boolean_true_node
4202                    : c_bool_true_node);
4203   arg = stabilize_reference (arg);
4204   switch (code)
4205     {
4206     case PREINCREMENT_EXPR:
4207       val = build (MODIFY_EXPR, TREE_TYPE (arg), arg, true_res);
4208       break;
4209     case POSTINCREMENT_EXPR:
4210       val = build (MODIFY_EXPR, TREE_TYPE (arg), arg, true_res);
4211       arg = save_expr (arg);
4212       val = build (COMPOUND_EXPR, TREE_TYPE (arg), val, arg);
4213       val = build (COMPOUND_EXPR, TREE_TYPE (arg), arg, val);
4214       break;
4215     case PREDECREMENT_EXPR:
4216       val = build (MODIFY_EXPR, TREE_TYPE (arg), arg, invert_truthvalue (arg));
4217       break;
4218     case POSTDECREMENT_EXPR:
4219       val = build (MODIFY_EXPR, TREE_TYPE (arg), arg, invert_truthvalue (arg));
4220       arg = save_expr (arg);
4221       val = build (COMPOUND_EXPR, TREE_TYPE (arg), val, arg);
4222       val = build (COMPOUND_EXPR, TREE_TYPE (arg), arg, val);
4223       break;
4224     default:
4225       abort ();
4226     }
4227   TREE_SIDE_EFFECTS (val) = 1;
4228   return val;
4229 }
4230 \f
4231 /* Common initialization before parsing options.  */
4232 void
4233 c_common_init_options (lang)
4234      enum c_language_kind lang;
4235 {
4236   c_language = lang;
4237   parse_in = cpp_create_reader (lang == clk_c || lang == clk_objective_c
4238                                 ? CLK_GNUC89 : CLK_GNUCXX);
4239   if (lang == clk_objective_c)
4240     cpp_get_options (parse_in)->objc = 1;
4241
4242   /* Mark as "unspecified" (see c_common_post_options).  */
4243   flag_bounds_check = -1;
4244 }
4245
4246 /* Post-switch processing.  */
4247 bool
4248 c_common_post_options ()
4249 {
4250   cpp_post_options (parse_in);
4251
4252   flag_inline_trees = 1;
4253
4254   /* Use tree inlining if possible.  Function instrumentation is only
4255      done in the RTL level, so we disable tree inlining.  */
4256   if (! flag_instrument_function_entry_exit)
4257     {
4258       if (!flag_no_inline)
4259         flag_no_inline = 1;
4260       if (flag_inline_functions)
4261         {
4262           flag_inline_trees = 2;
4263           flag_inline_functions = 0;
4264         }
4265     }
4266
4267   /* If still "unspecified", make it match -fbounded-pointers.  */
4268   if (flag_bounds_check == -1)
4269     flag_bounds_check = flag_bounded_pointers;
4270
4271   /* Special format checking options don't work without -Wformat; warn if
4272      they are used.  */
4273   if (warn_format_y2k && !warn_format)
4274     warning ("-Wformat-y2k ignored without -Wformat");
4275   if (warn_format_extra_args && !warn_format)
4276     warning ("-Wformat-extra-args ignored without -Wformat");
4277   if (warn_format_zero_length && !warn_format)
4278     warning ("-Wformat-zero-length ignored without -Wformat");
4279   if (warn_format_nonliteral && !warn_format)
4280     warning ("-Wformat-nonliteral ignored without -Wformat");
4281   if (warn_format_security && !warn_format)
4282     warning ("-Wformat-security ignored without -Wformat");
4283   if (warn_missing_format_attribute && !warn_format)
4284     warning ("-Wmissing-format-attribute ignored without -Wformat");
4285
4286   /* If an error has occurred in cpplib, note it so we fail
4287      immediately.  */
4288   errorcount += cpp_errors (parse_in);
4289
4290   return flag_preprocess_only;
4291 }
4292
4293 /* Hook that registers front end and target-specific built-ins.  */
4294 static void
4295 cb_register_builtins (pfile)
4296      cpp_reader *pfile;
4297 {
4298   /* -undef turns off target-specific built-ins.  */
4299   if (flag_undef)
4300     return;
4301
4302   if (c_language == clk_cplusplus)
4303     {
4304       if (SUPPORTS_ONE_ONLY)
4305         cpp_define (pfile, "__GXX_WEAK__=1");
4306       else
4307         cpp_define (pfile, "__GXX_WEAK__=0");
4308     }
4309
4310   /* libgcc needs to know this.  */
4311   if (USING_SJLJ_EXCEPTIONS)
4312     cpp_define (pfile, "__USING_SJLJ_EXCEPTIONS__");
4313
4314   /* stddef.h needs to know these.  */
4315   builtin_define_with_value ("__SIZE_TYPE__", SIZE_TYPE, 0);
4316   builtin_define_with_value ("__PTRDIFF_TYPE__", PTRDIFF_TYPE, 0);
4317   builtin_define_with_value ("__WCHAR_TYPE__", MODIFIED_WCHAR_TYPE, 0);
4318   builtin_define_with_value ("__WINT_TYPE__", WINT_TYPE, 0);
4319
4320   /* limits.h needs to know these.  */
4321   builtin_define_type_max ("__SCHAR_MAX__", signed_char_type_node, 0);
4322   builtin_define_type_max ("__SHRT_MAX__", short_integer_type_node, 0);
4323   builtin_define_type_max ("__INT_MAX__", integer_type_node, 0);
4324   builtin_define_type_max ("__LONG_MAX__", long_integer_type_node, 1);
4325   builtin_define_type_max ("__LONG_LONG_MAX__", long_long_integer_type_node, 2);
4326
4327   {
4328     char buf[8];
4329     sprintf (buf, "%d", (int) TYPE_PRECISION (signed_char_type_node));
4330     builtin_define_with_value ("__CHAR_BIT__", buf, 0);
4331   }
4332
4333   /* For use in assembly language.  */
4334   builtin_define_with_value ("__REGISTER_PREFIX__", REGISTER_PREFIX, 0);
4335   builtin_define_with_value ("__USER_LABEL_PREFIX__", user_label_prefix, 0);
4336
4337   /* Misc.  */
4338   builtin_define_with_value ("__VERSION__", version_string, 1);
4339
4340   /* Other target-independent built-ins determined by command-line
4341      options.  */
4342   if (optimize_size)
4343     cpp_define (pfile, "__OPTIMIZE_SIZE__");
4344   if (optimize)
4345     cpp_define (pfile, "__OPTIMIZE__");
4346
4347   if (flag_hosted)
4348     cpp_define (pfile, "__STDC_HOSTED__=1");
4349   else
4350     cpp_define (pfile, "__STDC_HOSTED__=0");
4351
4352   if (fast_math_flags_set_p ())
4353     cpp_define (pfile, "__FAST_MATH__");
4354   if (flag_no_inline)
4355     cpp_define (pfile, "__NO_INLINE__");
4356
4357   if (flag_iso)
4358     cpp_define (pfile, "__STRICT_ANSI__");
4359
4360   if (!flag_signed_char)
4361     cpp_define (pfile, "__CHAR_UNSIGNED__");
4362
4363   /* A straightforward target hook doesn't work, because of problems
4364      linking that hook's body when part of non-C front ends.  */
4365 # define preprocessing_asm_p() (cpp_get_options (pfile)->lang == CLK_ASM)
4366 # define builtin_define(TXT) cpp_define (pfile, TXT)
4367 # define builtin_assert(TXT) cpp_assert (pfile, TXT)
4368   TARGET_CPU_CPP_BUILTINS ();
4369   TARGET_OS_CPP_BUILTINS ();
4370 }
4371
4372 /* Pass an object-like macro.  If it doesn't lie in the user's
4373    namespace, defines it unconditionally.  Otherwise define a version
4374    with two leading underscores, and another version with two leading
4375    and trailing underscores, and define the original only if an ISO
4376    standard was not nominated.
4377
4378    e.g. passing "unix" defines "__unix", "__unix__" and possibly
4379    "unix".  Passing "_mips" defines "__mips", "__mips__" and possibly
4380    "_mips".  */
4381 void
4382 builtin_define_std (macro)
4383      const char *macro;
4384 {
4385   size_t len = strlen (macro);
4386   char *buff = alloca (len + 5);
4387   char *p = buff + 2;
4388   char *q = p + len;
4389
4390   /* prepend __ (or maybe just _) if in user's namespace.  */
4391   memcpy (p, macro, len + 1);
4392   if (!( *p == '_' && (p[1] == '_' || ISUPPER (p[1]))))
4393     {
4394       if (*p != '_')
4395         *--p = '_';
4396       if (p[1] != '_')
4397         *--p = '_';
4398     }
4399   cpp_define (parse_in, p);
4400
4401   /* If it was in user's namespace...  */
4402   if (p != buff + 2)
4403     {
4404       /* Define the macro with leading and following __.  */
4405       if (q[-1] != '_')
4406         *q++ = '_';
4407       if (q[-2] != '_')
4408         *q++ = '_';
4409       *q = '\0';
4410       cpp_define (parse_in, p);
4411
4412       /* Finally, define the original macro if permitted.  */
4413       if (!flag_iso)
4414         cpp_define (parse_in, macro);
4415     }
4416 }
4417
4418 /* Pass an object-like macro and a value to define it to.  The third
4419    parameter says whether or not to turn the value into a string
4420    constant.  */
4421 static void
4422 builtin_define_with_value (macro, expansion, is_str)
4423      const char *macro;
4424      const char *expansion;
4425      int is_str;
4426 {
4427   char *buf;
4428   size_t mlen = strlen (macro);
4429   size_t elen = strlen (expansion);
4430   size_t extra = 2;  /* space for an = and a NUL */
4431
4432   if (is_str)
4433     extra += 2;  /* space for two quote marks */
4434
4435   buf = alloca (mlen + elen + extra);
4436   if (is_str)
4437     sprintf (buf, "%s=\"%s\"", macro, expansion);
4438   else
4439     sprintf (buf, "%s=%s", macro, expansion);
4440
4441   cpp_define (parse_in, buf);
4442 }
4443
4444 /* Define MAX for TYPE based on the precision of the type, which is assumed
4445    to be signed.  IS_LONG is 1 for type "long" and 2 for "long long".  */
4446
4447 static void
4448 builtin_define_type_max (macro, type, is_long)
4449      const char *macro;
4450      tree type;
4451      int is_long;
4452 {
4453   const char *value;
4454   char *buf;
4455   size_t mlen, vlen, extra;
4456
4457   /* Pre-rendering the values mean we don't have to futz with printing a
4458      multi-word decimal value.  There are also a very limited number of
4459      precisions that we support, so it's really a waste of time.  */
4460   switch (TYPE_PRECISION (type))
4461     {
4462     case 8:
4463       value = "127";
4464       break;
4465     case 16:
4466       value = "32767";
4467       break;
4468     case 32:
4469       value = "2147483647";
4470       break;
4471     case 64:
4472       value = "9223372036854775807";
4473       break;
4474     case 128:
4475       value = "170141183460469231731687303715884105727";
4476       break;
4477     default:
4478       abort ();
4479     }
4480
4481   mlen = strlen (macro);
4482   vlen = strlen (value);
4483   extra = 2 + is_long;
4484   buf = alloca (mlen + vlen + extra);
4485
4486   sprintf (buf, "%s=%s%s", macro, value,
4487            (is_long == 1 ? "L" : is_long == 2 ? "LL" : ""));
4488
4489   cpp_define (parse_in, buf);
4490 }
4491
4492 /* Front end initialization common to C, ObjC and C++.  */
4493 const char *
4494 c_common_init (filename)
4495      const char *filename;
4496 {
4497   cpp_options *options = cpp_get_options (parse_in);
4498
4499   /* Set up preprocessor arithmetic.  Must be done after call to
4500      c_common_nodes_and_builtins for wchar_type_node to be good.  */
4501   options->precision = TYPE_PRECISION (intmax_type_node);
4502   options->char_precision = TYPE_PRECISION (char_type_node);
4503   options->int_precision = TYPE_PRECISION (integer_type_node);
4504   options->wchar_precision = TYPE_PRECISION (wchar_type_node);
4505   options->unsigned_wchar = TREE_UNSIGNED (wchar_type_node);
4506   options->unsigned_char = !flag_signed_char;
4507   options->warn_multichar = warn_multichar;
4508   options->stdc_0_in_system_headers = STDC_0_IN_SYSTEM_HEADERS;
4509
4510   /* We want -Wno-long-long to override -pedantic -std=non-c99
4511      whatever the ordering.  */
4512   options->warn_long_long = warn_long_long && !flag_isoc99 && pedantic;
4513
4514   /* Register preprocessor built-ins before calls to
4515      cpp_main_file.  */
4516   cpp_get_callbacks (parse_in)->register_builtins = cb_register_builtins;
4517
4518   /* NULL is passed up to toplev.c and we exit quickly.  */
4519   if (flag_preprocess_only)
4520     {
4521       cpp_preprocess_file (parse_in);
4522       return NULL;
4523     }
4524
4525   /* Do this before initializing pragmas, as then cpplib's hash table
4526      has been set up.  */
4527   filename = init_c_lex (filename);
4528
4529   init_pragma ();
4530
4531   if (!c_attrs_initialized)
4532     c_init_attributes ();
4533
4534   return filename;
4535 }
4536
4537 /* Common finish hook for the C, ObjC and C++ front ends.  */
4538 void
4539 c_common_finish ()
4540 {
4541   cpp_finish (parse_in);
4542
4543   /* For performance, avoid tearing down cpplib's internal structures.
4544      Call cpp_errors () instead of cpp_destroy ().  */
4545   errorcount += cpp_errors (parse_in);
4546 }
4547
4548 static void
4549 c_init_attributes ()
4550 {
4551   /* Fill in the built_in_attributes array.  */
4552 #define DEF_ATTR_NULL_TREE(ENUM)                \
4553   built_in_attributes[(int) ENUM] = NULL_TREE;
4554 #define DEF_ATTR_INT(ENUM, VALUE)                                            \
4555   built_in_attributes[(int) ENUM] = build_int_2 (VALUE, VALUE < 0 ? -1 : 0);
4556 #define DEF_ATTR_IDENT(ENUM, STRING)                            \
4557   built_in_attributes[(int) ENUM] = get_identifier (STRING);
4558 #define DEF_ATTR_TREE_LIST(ENUM, PURPOSE, VALUE, CHAIN) \
4559   built_in_attributes[(int) ENUM]                       \
4560     = tree_cons (built_in_attributes[(int) PURPOSE],    \
4561                  built_in_attributes[(int) VALUE],      \
4562                  built_in_attributes[(int) CHAIN]);
4563 #define DEF_FN_ATTR(NAME, ATTRS, PREDICATE) /* No initialization needed.  */
4564 #include "builtin-attrs.def"
4565 #undef DEF_ATTR_NULL_TREE
4566 #undef DEF_ATTR_INT
4567 #undef DEF_ATTR_IDENT
4568 #undef DEF_ATTR_TREE_LIST
4569 #undef DEF_FN_ATTR
4570   c_attrs_initialized = true;
4571 }
4572
4573 /* Depending on the name of DECL, apply default attributes to it.  */
4574
4575 void
4576 c_common_insert_default_attributes (decl)
4577      tree decl;
4578 {
4579   tree name = DECL_NAME (decl);
4580
4581   if (!c_attrs_initialized)
4582     c_init_attributes ();
4583
4584 #define DEF_ATTR_NULL_TREE(ENUM) /* Nothing needed after initialization.  */
4585 #define DEF_ATTR_INT(ENUM, VALUE)
4586 #define DEF_ATTR_IDENT(ENUM, STRING)
4587 #define DEF_ATTR_TREE_LIST(ENUM, PURPOSE, VALUE, CHAIN)
4588 #define DEF_FN_ATTR(NAME, ATTRS, PREDICATE)                     \
4589   if ((PREDICATE) && name == built_in_attributes[(int) NAME])   \
4590     decl_attributes (&decl, built_in_attributes[(int) ATTRS],   \
4591                      ATTR_FLAG_BUILT_IN);
4592 #include "builtin-attrs.def"
4593 #undef DEF_ATTR_NULL_TREE
4594 #undef DEF_ATTR_INT
4595 #undef DEF_ATTR_IDENT
4596 #undef DEF_ATTR_TREE_LIST
4597 #undef DEF_FN_ATTR
4598 }
4599
4600 /* Output a -Wshadow warning MSGID about NAME, an IDENTIFIER_NODE, and
4601    additionally give the location of the previous declaration DECL.  */
4602 void
4603 shadow_warning (msgid, name, decl)
4604      const char *msgid;
4605      tree name, decl;
4606 {
4607   warning ("declaration of `%s' shadows %s", IDENTIFIER_POINTER (name), msgid);
4608   warning_with_file_and_line (DECL_SOURCE_FILE (decl),
4609                               DECL_SOURCE_LINE (decl),
4610                               "shadowed declaration is here");
4611 }
4612
4613 /* Attribute handlers common to C front ends.  */
4614
4615 /* Handle a "packed" attribute; arguments as in
4616    struct attribute_spec.handler.  */
4617
4618 static tree
4619 handle_packed_attribute (node, name, args, flags, no_add_attrs)
4620      tree *node;
4621      tree name;
4622      tree args ATTRIBUTE_UNUSED;
4623      int flags;
4624      bool *no_add_attrs;
4625 {
4626   tree *type = NULL;
4627   if (DECL_P (*node))
4628     {
4629       if (TREE_CODE (*node) == TYPE_DECL)
4630         type = &TREE_TYPE (*node);
4631     }
4632   else
4633     type = node;
4634
4635   if (type)
4636     {
4637       if (!(flags & (int) ATTR_FLAG_TYPE_IN_PLACE))
4638         *type = build_type_copy (*type);
4639       TYPE_PACKED (*type) = 1;
4640     }
4641   else if (TREE_CODE (*node) == FIELD_DECL)
4642     DECL_PACKED (*node) = 1;
4643   /* We can't set DECL_PACKED for a VAR_DECL, because the bit is
4644      used for DECL_REGISTER.  It wouldn't mean anything anyway.  */
4645   else
4646     {
4647       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
4648       *no_add_attrs = true;
4649     }
4650
4651   return NULL_TREE;
4652 }
4653
4654 /* Handle a "nocommon" attribute; arguments as in
4655    struct attribute_spec.handler.  */
4656
4657 static tree
4658 handle_nocommon_attribute (node, name, args, flags, no_add_attrs)
4659      tree *node;
4660      tree name;
4661      tree args ATTRIBUTE_UNUSED;
4662      int flags ATTRIBUTE_UNUSED;
4663      bool *no_add_attrs;
4664 {
4665   if (TREE_CODE (*node) == VAR_DECL)
4666     DECL_COMMON (*node) = 0;
4667   else
4668     {
4669       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
4670       *no_add_attrs = true;
4671     }
4672
4673   return NULL_TREE;
4674 }
4675
4676 /* Handle a "common" attribute; arguments as in
4677    struct attribute_spec.handler.  */
4678
4679 static tree
4680 handle_common_attribute (node, name, args, flags, no_add_attrs)
4681      tree *node;
4682      tree name;
4683      tree args ATTRIBUTE_UNUSED;
4684      int flags ATTRIBUTE_UNUSED;
4685      bool *no_add_attrs;
4686 {
4687   if (TREE_CODE (*node) == VAR_DECL)
4688     DECL_COMMON (*node) = 1;
4689   else
4690     {
4691       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
4692       *no_add_attrs = true;
4693     }
4694
4695   return NULL_TREE;
4696 }
4697
4698 /* Handle a "noreturn" attribute; arguments as in
4699    struct attribute_spec.handler.  */
4700
4701 static tree
4702 handle_noreturn_attribute (node, name, args, flags, no_add_attrs)
4703      tree *node;
4704      tree name;
4705      tree args ATTRIBUTE_UNUSED;
4706      int flags ATTRIBUTE_UNUSED;
4707      bool *no_add_attrs;
4708 {
4709   tree type = TREE_TYPE (*node);
4710
4711   /* See FIXME comment in c_common_attribute_table.  */
4712   if (TREE_CODE (*node) == FUNCTION_DECL)
4713     TREE_THIS_VOLATILE (*node) = 1;
4714   else if (TREE_CODE (type) == POINTER_TYPE
4715            && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE)
4716     TREE_TYPE (*node)
4717       = build_pointer_type
4718         (build_type_variant (TREE_TYPE (type),
4719                              TREE_READONLY (TREE_TYPE (type)), 1));
4720   else
4721     {
4722       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
4723       *no_add_attrs = true;
4724     }
4725
4726   return NULL_TREE;
4727 }
4728
4729 /* Handle a "noinline" attribute; arguments as in
4730    struct attribute_spec.handler.  */
4731
4732 static tree
4733 handle_noinline_attribute (node, name, args, flags, no_add_attrs)
4734      tree *node;
4735      tree name;
4736      tree args ATTRIBUTE_UNUSED;
4737      int flags ATTRIBUTE_UNUSED;
4738      bool *no_add_attrs;
4739 {
4740   if (TREE_CODE (*node) == FUNCTION_DECL)
4741     DECL_UNINLINABLE (*node) = 1;
4742   else
4743     {
4744       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
4745       *no_add_attrs = true;
4746     }
4747
4748   return NULL_TREE;
4749 }
4750
4751 /* Handle a "always_inline" attribute; arguments as in
4752    struct attribute_spec.handler.  */
4753
4754 static tree
4755 handle_always_inline_attribute (node, name, args, flags, no_add_attrs)
4756      tree *node;
4757      tree name;
4758      tree args ATTRIBUTE_UNUSED;
4759      int flags ATTRIBUTE_UNUSED;
4760      bool *no_add_attrs;
4761 {
4762   if (TREE_CODE (*node) == FUNCTION_DECL)
4763     {
4764       /* Do nothing else, just set the attribute.  We'll get at
4765          it later with lookup_attribute.  */
4766     }
4767   else
4768     {
4769       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
4770       *no_add_attrs = true;
4771     }
4772
4773   return NULL_TREE;
4774 }
4775
4776 /* Handle a "used" attribute; arguments as in
4777    struct attribute_spec.handler.  */
4778
4779 static tree
4780 handle_used_attribute (node, name, args, flags, no_add_attrs)
4781      tree *node;
4782      tree name;
4783      tree args ATTRIBUTE_UNUSED;
4784      int flags ATTRIBUTE_UNUSED;
4785      bool *no_add_attrs;
4786 {
4787   if (TREE_CODE (*node) == FUNCTION_DECL)
4788     TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (*node))
4789       = TREE_USED (*node) = 1;
4790   else
4791     {
4792       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
4793       *no_add_attrs = true;
4794     }
4795
4796   return NULL_TREE;
4797 }
4798
4799 /* Handle a "unused" attribute; arguments as in
4800    struct attribute_spec.handler.  */
4801
4802 static tree
4803 handle_unused_attribute (node, name, args, flags, no_add_attrs)
4804      tree *node;
4805      tree name;
4806      tree args ATTRIBUTE_UNUSED;
4807      int flags;
4808      bool *no_add_attrs;
4809 {
4810   if (DECL_P (*node))
4811     {
4812       tree decl = *node;
4813
4814       if (TREE_CODE (decl) == PARM_DECL
4815           || TREE_CODE (decl) == VAR_DECL
4816           || TREE_CODE (decl) == FUNCTION_DECL
4817           || TREE_CODE (decl) == LABEL_DECL
4818           || TREE_CODE (decl) == TYPE_DECL)
4819         TREE_USED (decl) = 1;
4820       else
4821         {
4822           warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
4823           *no_add_attrs = true;
4824         }
4825     }
4826   else
4827     {
4828       if (!(flags & (int) ATTR_FLAG_TYPE_IN_PLACE))
4829         *node = build_type_copy (*node);
4830       TREE_USED (*node) = 1;
4831     }
4832
4833   return NULL_TREE;
4834 }
4835
4836 /* Handle a "const" attribute; arguments as in
4837    struct attribute_spec.handler.  */
4838
4839 static tree
4840 handle_const_attribute (node, name, args, flags, no_add_attrs)
4841      tree *node;
4842      tree name;
4843      tree args ATTRIBUTE_UNUSED;
4844      int flags ATTRIBUTE_UNUSED;
4845      bool *no_add_attrs;
4846 {
4847   tree type = TREE_TYPE (*node);
4848
4849   /* See FIXME comment on noreturn in c_common_attribute_table.  */
4850   if (TREE_CODE (*node) == FUNCTION_DECL)
4851     TREE_READONLY (*node) = 1;
4852   else if (TREE_CODE (type) == POINTER_TYPE
4853            && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE)
4854     TREE_TYPE (*node)
4855       = build_pointer_type
4856         (build_type_variant (TREE_TYPE (type), 1,
4857                              TREE_THIS_VOLATILE (TREE_TYPE (type))));
4858   else
4859     {
4860       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
4861       *no_add_attrs = true;
4862     }
4863
4864   return NULL_TREE;
4865 }
4866
4867 /* Handle a "transparent_union" attribute; arguments as in
4868    struct attribute_spec.handler.  */
4869
4870 static tree
4871 handle_transparent_union_attribute (node, name, args, flags, no_add_attrs)
4872      tree *node;
4873      tree name;
4874      tree args ATTRIBUTE_UNUSED;
4875      int flags;
4876      bool *no_add_attrs;
4877 {
4878   tree decl = NULL_TREE;
4879   tree *type = NULL;
4880   int is_type = 0;
4881
4882   if (DECL_P (*node))
4883     {
4884       decl = *node;
4885       type = &TREE_TYPE (decl);
4886       is_type = TREE_CODE (*node) == TYPE_DECL;
4887     }
4888   else if (TYPE_P (*node))
4889     type = node, is_type = 1;
4890
4891   if (is_type
4892       && TREE_CODE (*type) == UNION_TYPE
4893       && (decl == 0
4894           || (TYPE_FIELDS (*type) != 0
4895               && TYPE_MODE (*type) == DECL_MODE (TYPE_FIELDS (*type)))))
4896     {
4897       if (!(flags & (int) ATTR_FLAG_TYPE_IN_PLACE))
4898         *type = build_type_copy (*type);
4899       TYPE_TRANSPARENT_UNION (*type) = 1;
4900     }
4901   else if (decl != 0 && TREE_CODE (decl) == PARM_DECL
4902            && TREE_CODE (*type) == UNION_TYPE
4903            && TYPE_MODE (*type) == DECL_MODE (TYPE_FIELDS (*type)))
4904     DECL_TRANSPARENT_UNION (decl) = 1;
4905   else
4906     {
4907       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
4908       *no_add_attrs = true;
4909     }
4910
4911   return NULL_TREE;
4912 }
4913
4914 /* Handle a "constructor" attribute; arguments as in
4915    struct attribute_spec.handler.  */
4916
4917 static tree
4918 handle_constructor_attribute (node, name, args, flags, no_add_attrs)
4919      tree *node;
4920      tree name;
4921      tree args ATTRIBUTE_UNUSED;
4922      int flags ATTRIBUTE_UNUSED;
4923      bool *no_add_attrs;
4924 {
4925   tree decl = *node;
4926   tree type = TREE_TYPE (decl);
4927
4928   if (TREE_CODE (decl) == FUNCTION_DECL
4929       && TREE_CODE (type) == FUNCTION_TYPE
4930       && decl_function_context (decl) == 0)
4931     {
4932       DECL_STATIC_CONSTRUCTOR (decl) = 1;
4933       TREE_USED (decl) = 1;
4934     }
4935   else
4936     {
4937       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
4938       *no_add_attrs = true;
4939     }
4940
4941   return NULL_TREE;
4942 }
4943
4944 /* Handle a "destructor" attribute; arguments as in
4945    struct attribute_spec.handler.  */
4946
4947 static tree
4948 handle_destructor_attribute (node, name, args, flags, no_add_attrs)
4949      tree *node;
4950      tree name;
4951      tree args ATTRIBUTE_UNUSED;
4952      int flags ATTRIBUTE_UNUSED;
4953      bool *no_add_attrs;
4954 {
4955   tree decl = *node;
4956   tree type = TREE_TYPE (decl);
4957
4958   if (TREE_CODE (decl) == FUNCTION_DECL
4959       && TREE_CODE (type) == FUNCTION_TYPE
4960       && decl_function_context (decl) == 0)
4961     {
4962       DECL_STATIC_DESTRUCTOR (decl) = 1;
4963       TREE_USED (decl) = 1;
4964     }
4965   else
4966     {
4967       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
4968       *no_add_attrs = true;
4969     }
4970
4971   return NULL_TREE;
4972 }
4973
4974 /* Handle a "mode" attribute; arguments as in
4975    struct attribute_spec.handler.  */
4976
4977 static tree
4978 handle_mode_attribute (node, name, args, flags, no_add_attrs)
4979      tree *node;
4980      tree name;
4981      tree args;
4982      int flags ATTRIBUTE_UNUSED;
4983      bool *no_add_attrs;
4984 {
4985   tree type = *node;
4986
4987   *no_add_attrs = true;
4988
4989   if (TREE_CODE (TREE_VALUE (args)) != IDENTIFIER_NODE)
4990     warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
4991   else
4992     {
4993       int j;
4994       const char *p = IDENTIFIER_POINTER (TREE_VALUE (args));
4995       int len = strlen (p);
4996       enum machine_mode mode = VOIDmode;
4997       tree typefm;
4998
4999       if (len > 4 && p[0] == '_' && p[1] == '_'
5000           && p[len - 1] == '_' && p[len - 2] == '_')
5001         {
5002           char *newp = (char *) alloca (len - 1);
5003
5004           strcpy (newp, &p[2]);
5005           newp[len - 4] = '\0';
5006           p = newp;
5007         }
5008
5009       /* Change this type to have a type with the specified mode.
5010          First check for the special modes.  */
5011       if (! strcmp (p, "byte"))
5012         mode = byte_mode;
5013       else if (!strcmp (p, "word"))
5014         mode = word_mode;
5015       else if (! strcmp (p, "pointer"))
5016         mode = ptr_mode;
5017       else
5018         for (j = 0; j < NUM_MACHINE_MODES; j++)
5019           if (!strcmp (p, GET_MODE_NAME (j)))
5020             mode = (enum machine_mode) j;
5021
5022       if (mode == VOIDmode)
5023         error ("unknown machine mode `%s'", p);
5024       else if (0 == (typefm = (*lang_hooks.types.type_for_mode)
5025                      (mode, TREE_UNSIGNED (type))))
5026         error ("no data type for mode `%s'", p);
5027       else
5028         {
5029           /* If this is a vector, make sure we either have hardware
5030              support, or we can emulate it.  */
5031           if ((GET_MODE_CLASS (mode) == MODE_VECTOR_INT
5032                || GET_MODE_CLASS (mode) == MODE_VECTOR_FLOAT)
5033               && !vector_mode_valid_p (mode))
5034             {
5035               error ("unable to emulate '%s'", GET_MODE_NAME (mode));
5036               return NULL_TREE;
5037             }
5038
5039           *node = typefm;
5040           /* No need to layout the type here.  The caller should do this.  */
5041         }
5042     }
5043
5044   return NULL_TREE;
5045 }
5046
5047 /* Handle a "section" attribute; arguments as in
5048    struct attribute_spec.handler.  */
5049
5050 static tree
5051 handle_section_attribute (node, name, args, flags, no_add_attrs)
5052      tree *node;
5053      tree name ATTRIBUTE_UNUSED;
5054      tree args;
5055      int flags ATTRIBUTE_UNUSED;
5056      bool *no_add_attrs;
5057 {
5058   tree decl = *node;
5059
5060   if (targetm.have_named_sections)
5061     {
5062       if ((TREE_CODE (decl) == FUNCTION_DECL
5063            || TREE_CODE (decl) == VAR_DECL)
5064           && TREE_CODE (TREE_VALUE (args)) == STRING_CST)
5065         {
5066           if (TREE_CODE (decl) == VAR_DECL
5067               && current_function_decl != NULL_TREE
5068               && ! TREE_STATIC (decl))
5069             {
5070               error_with_decl (decl,
5071                                "section attribute cannot be specified for local variables");
5072               *no_add_attrs = true;
5073             }
5074
5075           /* The decl may have already been given a section attribute
5076              from a previous declaration.  Ensure they match.  */
5077           else if (DECL_SECTION_NAME (decl) != NULL_TREE
5078                    && strcmp (TREE_STRING_POINTER (DECL_SECTION_NAME (decl)),
5079                               TREE_STRING_POINTER (TREE_VALUE (args))) != 0)
5080             {
5081               error_with_decl (*node,
5082                                "section of `%s' conflicts with previous declaration");
5083               *no_add_attrs = true;
5084             }
5085           else
5086             DECL_SECTION_NAME (decl) = TREE_VALUE (args);
5087         }
5088       else
5089         {
5090           error_with_decl (*node,
5091                            "section attribute not allowed for `%s'");
5092           *no_add_attrs = true;
5093         }
5094     }
5095   else
5096     {
5097       error_with_decl (*node,
5098                        "section attributes are not supported for this target");
5099       *no_add_attrs = true;
5100     }
5101
5102   return NULL_TREE;
5103 }
5104
5105 /* Handle a "aligned" attribute; arguments as in
5106    struct attribute_spec.handler.  */
5107
5108 static tree
5109 handle_aligned_attribute (node, name, args, flags, no_add_attrs)
5110      tree *node;
5111      tree name ATTRIBUTE_UNUSED;
5112      tree args;
5113      int flags;
5114      bool *no_add_attrs;
5115 {
5116   tree decl = NULL_TREE;
5117   tree *type = NULL;
5118   int is_type = 0;
5119   tree align_expr = (args ? TREE_VALUE (args)
5120                      : size_int (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
5121   int i;
5122
5123   if (DECL_P (*node))
5124     {
5125       decl = *node;
5126       type = &TREE_TYPE (decl);
5127       is_type = TREE_CODE (*node) == TYPE_DECL;
5128     }
5129   else if (TYPE_P (*node))
5130     type = node, is_type = 1;
5131
5132   /* Strip any NOPs of any kind.  */
5133   while (TREE_CODE (align_expr) == NOP_EXPR
5134          || TREE_CODE (align_expr) == CONVERT_EXPR
5135          || TREE_CODE (align_expr) == NON_LVALUE_EXPR)
5136     align_expr = TREE_OPERAND (align_expr, 0);
5137
5138   if (TREE_CODE (align_expr) != INTEGER_CST)
5139     {
5140       error ("requested alignment is not a constant");
5141       *no_add_attrs = true;
5142     }
5143   else if ((i = tree_log2 (align_expr)) == -1)
5144     {
5145       error ("requested alignment is not a power of 2");
5146       *no_add_attrs = true;
5147     }
5148   else if (i > HOST_BITS_PER_INT - 2)
5149     {
5150       error ("requested alignment is too large");
5151       *no_add_attrs = true;
5152     }
5153   else if (is_type)
5154     {
5155       /* If we have a TYPE_DECL, then copy the type, so that we
5156          don't accidentally modify a builtin type.  See pushdecl.  */
5157       if (decl && TREE_TYPE (decl) != error_mark_node
5158           && DECL_ORIGINAL_TYPE (decl) == NULL_TREE)
5159         {
5160           tree tt = TREE_TYPE (decl);
5161           *type = build_type_copy (*type);
5162           DECL_ORIGINAL_TYPE (decl) = tt;
5163           TYPE_NAME (*type) = decl;
5164           TREE_USED (*type) = TREE_USED (decl);
5165           TREE_TYPE (decl) = *type;
5166         }
5167       else if (!(flags & (int) ATTR_FLAG_TYPE_IN_PLACE))
5168         *type = build_type_copy (*type);
5169
5170       TYPE_ALIGN (*type) = (1 << i) * BITS_PER_UNIT;
5171       TYPE_USER_ALIGN (*type) = 1;
5172     }
5173   else if (TREE_CODE (decl) != VAR_DECL
5174            && TREE_CODE (decl) != FIELD_DECL)
5175     {
5176       error_with_decl (decl,
5177                        "alignment may not be specified for `%s'");
5178       *no_add_attrs = true;
5179     }
5180   else
5181     {
5182       DECL_ALIGN (decl) = (1 << i) * BITS_PER_UNIT;
5183       DECL_USER_ALIGN (decl) = 1;
5184     }
5185
5186   return NULL_TREE;
5187 }
5188
5189 /* Handle a "weak" attribute; arguments as in
5190    struct attribute_spec.handler.  */
5191
5192 static tree
5193 handle_weak_attribute (node, name, args, flags, no_add_attrs)
5194      tree *node;
5195      tree name ATTRIBUTE_UNUSED;
5196      tree args ATTRIBUTE_UNUSED;
5197      int flags ATTRIBUTE_UNUSED;
5198      bool *no_add_attrs ATTRIBUTE_UNUSED;
5199 {
5200   declare_weak (*node);
5201
5202   return NULL_TREE;
5203 }
5204
5205 /* Handle an "alias" attribute; arguments as in
5206    struct attribute_spec.handler.  */
5207
5208 static tree
5209 handle_alias_attribute (node, name, args, flags, no_add_attrs)
5210      tree *node;
5211      tree name;
5212      tree args;
5213      int flags ATTRIBUTE_UNUSED;
5214      bool *no_add_attrs;
5215 {
5216   tree decl = *node;
5217
5218   if ((TREE_CODE (decl) == FUNCTION_DECL && DECL_INITIAL (decl))
5219       || (TREE_CODE (decl) != FUNCTION_DECL && ! DECL_EXTERNAL (decl)))
5220     {
5221       error_with_decl (decl,
5222                        "`%s' defined both normally and as an alias");
5223       *no_add_attrs = true;
5224     }
5225   else if (decl_function_context (decl) == 0)
5226     {
5227       tree id;
5228
5229       id = TREE_VALUE (args);
5230       if (TREE_CODE (id) != STRING_CST)
5231         {
5232           error ("alias arg not a string");
5233           *no_add_attrs = true;
5234           return NULL_TREE;
5235         }
5236       id = get_identifier (TREE_STRING_POINTER (id));
5237       /* This counts as a use of the object pointed to.  */
5238       TREE_USED (id) = 1;
5239
5240       if (TREE_CODE (decl) == FUNCTION_DECL)
5241         DECL_INITIAL (decl) = error_mark_node;
5242       else
5243         DECL_EXTERNAL (decl) = 0;
5244     }
5245   else
5246     {
5247       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
5248       *no_add_attrs = true;
5249     }
5250
5251   return NULL_TREE;
5252 }
5253
5254 /* Handle an "visibility" attribute; arguments as in
5255    struct attribute_spec.handler.  */
5256
5257 static tree
5258 handle_visibility_attribute (node, name, args, flags, no_add_attrs)
5259      tree *node;
5260      tree name;
5261      tree args;
5262      int flags ATTRIBUTE_UNUSED;
5263      bool *no_add_attrs;
5264 {
5265   tree decl = *node;
5266
5267   if (decl_function_context (decl) != 0 || ! TREE_PUBLIC (decl))
5268     {
5269       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
5270       *no_add_attrs = true;
5271     }
5272   else
5273     {
5274       tree id;
5275
5276       id = TREE_VALUE (args);
5277       if (TREE_CODE (id) != STRING_CST)
5278         {
5279           error ("visibility arg not a string");
5280           *no_add_attrs = true;
5281           return NULL_TREE;
5282         }
5283       if (strcmp (TREE_STRING_POINTER (id), "hidden")
5284           && strcmp (TREE_STRING_POINTER (id), "protected")
5285           && strcmp (TREE_STRING_POINTER (id), "internal"))
5286         {
5287           error ("visibility arg must be one of \"hidden\", \"protected\" or \"internal\"");
5288           *no_add_attrs = true;
5289           return NULL_TREE;
5290         }
5291     }
5292
5293   return NULL_TREE;
5294 }
5295
5296 /* Handle a "no_instrument_function" attribute; arguments as in
5297    struct attribute_spec.handler.  */
5298
5299 static tree
5300 handle_no_instrument_function_attribute (node, name, args, flags, no_add_attrs)
5301      tree *node;
5302      tree name;
5303      tree args ATTRIBUTE_UNUSED;
5304      int flags ATTRIBUTE_UNUSED;
5305      bool *no_add_attrs;
5306 {
5307   tree decl = *node;
5308
5309   if (TREE_CODE (decl) != FUNCTION_DECL)
5310     {
5311       error_with_decl (decl,
5312                        "`%s' attribute applies only to functions",
5313                        IDENTIFIER_POINTER (name));
5314       *no_add_attrs = true;
5315     }
5316   else if (DECL_INITIAL (decl))
5317     {
5318       error_with_decl (decl,
5319                        "can't set `%s' attribute after definition",
5320                        IDENTIFIER_POINTER (name));
5321       *no_add_attrs = true;
5322     }
5323   else
5324     DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (decl) = 1;
5325
5326   return NULL_TREE;
5327 }
5328
5329 /* Handle a "malloc" attribute; arguments as in
5330    struct attribute_spec.handler.  */
5331
5332 static tree
5333 handle_malloc_attribute (node, name, args, flags, no_add_attrs)
5334      tree *node;
5335      tree name;
5336      tree args ATTRIBUTE_UNUSED;
5337      int flags ATTRIBUTE_UNUSED;
5338      bool *no_add_attrs;
5339 {
5340   if (TREE_CODE (*node) == FUNCTION_DECL)
5341     DECL_IS_MALLOC (*node) = 1;
5342   /* ??? TODO: Support types.  */
5343   else
5344     {
5345       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
5346       *no_add_attrs = true;
5347     }
5348
5349   return NULL_TREE;
5350 }
5351
5352 /* Handle a "no_limit_stack" attribute; arguments as in
5353    struct attribute_spec.handler.  */
5354
5355 static tree
5356 handle_no_limit_stack_attribute (node, name, args, flags, no_add_attrs)
5357      tree *node;
5358      tree name;
5359      tree args ATTRIBUTE_UNUSED;
5360      int flags ATTRIBUTE_UNUSED;
5361      bool *no_add_attrs;
5362 {
5363   tree decl = *node;
5364
5365   if (TREE_CODE (decl) != FUNCTION_DECL)
5366     {
5367       error_with_decl (decl,
5368                        "`%s' attribute applies only to functions",
5369                        IDENTIFIER_POINTER (name));
5370       *no_add_attrs = true;
5371     }
5372   else if (DECL_INITIAL (decl))
5373     {
5374       error_with_decl (decl,
5375                        "can't set `%s' attribute after definition",
5376                        IDENTIFIER_POINTER (name));
5377       *no_add_attrs = true;
5378     }
5379   else
5380     DECL_NO_LIMIT_STACK (decl) = 1;
5381
5382   return NULL_TREE;
5383 }
5384
5385 /* Handle a "pure" attribute; arguments as in
5386    struct attribute_spec.handler.  */
5387
5388 static tree
5389 handle_pure_attribute (node, name, args, flags, no_add_attrs)
5390      tree *node;
5391      tree name;
5392      tree args ATTRIBUTE_UNUSED;
5393      int flags ATTRIBUTE_UNUSED;
5394      bool *no_add_attrs;
5395 {
5396   if (TREE_CODE (*node) == FUNCTION_DECL)
5397     DECL_IS_PURE (*node) = 1;
5398   /* ??? TODO: Support types.  */
5399   else
5400     {
5401       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
5402       *no_add_attrs = true;
5403     }
5404
5405   return NULL_TREE;
5406 }
5407
5408 /* Handle a "deprecated" attribute; arguments as in
5409    struct attribute_spec.handler.  */
5410
5411 static tree
5412 handle_deprecated_attribute (node, name, args, flags, no_add_attrs)
5413      tree *node;
5414      tree name;
5415      tree args ATTRIBUTE_UNUSED;
5416      int flags;
5417      bool *no_add_attrs;
5418 {
5419   tree type = NULL_TREE;
5420   int warn = 0;
5421   const char *what = NULL;
5422
5423   if (DECL_P (*node))
5424     {
5425       tree decl = *node;
5426       type = TREE_TYPE (decl);
5427
5428       if (TREE_CODE (decl) == TYPE_DECL
5429           || TREE_CODE (decl) == PARM_DECL
5430           || TREE_CODE (decl) == VAR_DECL
5431           || TREE_CODE (decl) == FUNCTION_DECL
5432           || TREE_CODE (decl) == FIELD_DECL)
5433         TREE_DEPRECATED (decl) = 1;
5434       else
5435         warn = 1;
5436     }
5437   else if (TYPE_P (*node))
5438     {
5439       if (!(flags & (int) ATTR_FLAG_TYPE_IN_PLACE))
5440         *node = build_type_copy (*node);
5441       TREE_DEPRECATED (*node) = 1;
5442       type = *node;
5443     }
5444   else
5445     warn = 1;
5446
5447   if (warn)
5448     {
5449       *no_add_attrs = true;
5450       if (type && TYPE_NAME (type))
5451         {
5452           if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE)
5453             what = IDENTIFIER_POINTER (TYPE_NAME (*node));
5454           else if (TREE_CODE (TYPE_NAME (type)) == TYPE_DECL
5455                    && DECL_NAME (TYPE_NAME (type)))
5456             what = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type)));
5457         }
5458       if (what)
5459         warning ("`%s' attribute ignored for `%s'",
5460                   IDENTIFIER_POINTER (name), what);
5461       else
5462         warning ("`%s' attribute ignored",
5463                       IDENTIFIER_POINTER (name));
5464     }
5465
5466   return NULL_TREE;
5467 }
5468
5469 /* Keep a list of vector type nodes we created in handle_vector_size_attribute,
5470    to prevent us from duplicating type nodes unnecessarily.
5471    The normal mechanism to prevent duplicates is to use type_hash_canon, but
5472    since we want to distinguish types that are essentially identical (except
5473    for their debug representation), we use a local list here.  */
5474 static tree vector_type_node_list = 0;
5475
5476 /* Handle a "vector_size" attribute; arguments as in
5477    struct attribute_spec.handler.  */
5478
5479 static tree
5480 handle_vector_size_attribute (node, name, args, flags, no_add_attrs)
5481      tree *node;
5482      tree name;
5483      tree args;
5484      int flags ATTRIBUTE_UNUSED;
5485      bool *no_add_attrs;
5486 {
5487   unsigned HOST_WIDE_INT vecsize, nunits;
5488   enum machine_mode mode, orig_mode, new_mode;
5489   tree type = *node, new_type = NULL_TREE;
5490   tree type_list_node;
5491
5492   *no_add_attrs = true;
5493
5494   if (! host_integerp (TREE_VALUE (args), 1))
5495     {
5496       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
5497       return NULL_TREE;
5498     }
5499
5500   /* Get the vector size (in bytes).  */
5501   vecsize = tree_low_cst (TREE_VALUE (args), 1);
5502
5503   /* We need to provide for vector pointers, vector arrays, and
5504      functions returning vectors.  For example:
5505
5506        __attribute__((vector_size(16))) short *foo;
5507
5508      In this case, the mode is SI, but the type being modified is
5509      HI, so we need to look further.  */
5510
5511   while (POINTER_TYPE_P (type)
5512          || TREE_CODE (type) == FUNCTION_TYPE
5513          || TREE_CODE (type) == ARRAY_TYPE)
5514     type = TREE_TYPE (type);
5515
5516   /* Get the mode of the type being modified.  */
5517   orig_mode = TYPE_MODE (type);
5518
5519   if (TREE_CODE (type) == RECORD_TYPE
5520       || (GET_MODE_CLASS (orig_mode) != MODE_FLOAT
5521           && GET_MODE_CLASS (orig_mode) != MODE_INT)
5522       || ! host_integerp (TYPE_SIZE_UNIT (type), 1))
5523     {
5524       error ("invalid vector type for attribute `%s'",
5525              IDENTIFIER_POINTER (name));
5526       return NULL_TREE;
5527     }
5528
5529   /* Calculate how many units fit in the vector.  */
5530   nunits = vecsize / tree_low_cst (TYPE_SIZE_UNIT (type), 1);
5531
5532   /* Find a suitably sized vector.  */
5533   new_mode = VOIDmode;
5534   for (mode = GET_CLASS_NARROWEST_MODE (GET_MODE_CLASS (orig_mode) == MODE_INT
5535                                         ? MODE_VECTOR_INT
5536                                         : MODE_VECTOR_FLOAT);
5537        mode != VOIDmode;
5538        mode = GET_MODE_WIDER_MODE (mode))
5539     if (vecsize == GET_MODE_SIZE (mode)
5540         && nunits == (unsigned HOST_WIDE_INT) GET_MODE_NUNITS (mode))
5541       {
5542         new_mode = mode;
5543         break;
5544       }
5545
5546     if (new_mode == VOIDmode)
5547     {
5548       error ("no vector mode with the size and type specified could be found");
5549       return NULL_TREE;
5550     }
5551
5552   for (type_list_node = vector_type_node_list; type_list_node;
5553        type_list_node = TREE_CHAIN (type_list_node))
5554     {
5555       tree other_type = TREE_VALUE (type_list_node);
5556       tree record = TYPE_DEBUG_REPRESENTATION_TYPE (other_type);
5557       tree fields = TYPE_FIELDS (record);
5558       tree field_type = TREE_TYPE (fields);
5559       tree array_type = TREE_TYPE (field_type);
5560       if (TREE_CODE (fields) != FIELD_DECL
5561           || TREE_CODE (field_type) != ARRAY_TYPE)
5562         abort ();
5563
5564       if (TYPE_MODE (other_type) == mode && type == array_type)
5565         {
5566           new_type = other_type;
5567           break;
5568         }
5569     }
5570
5571   if (new_type == NULL_TREE)
5572     {
5573       tree index, array, rt, list_node;
5574
5575       new_type = (*lang_hooks.types.type_for_mode) (new_mode,
5576                                                     TREE_UNSIGNED (type));
5577
5578       if (!new_type)
5579         {
5580           error ("no vector mode with the size and type specified could be found");
5581           return NULL_TREE;
5582         }
5583
5584       new_type = build_type_copy (new_type);
5585
5586       /* If this is a vector, make sure we either have hardware
5587          support, or we can emulate it.  */
5588       if ((GET_MODE_CLASS (mode) == MODE_VECTOR_INT
5589            || GET_MODE_CLASS (mode) == MODE_VECTOR_FLOAT)
5590           && !vector_mode_valid_p (mode))
5591         {
5592           error ("unable to emulate '%s'", GET_MODE_NAME (mode));
5593           return NULL_TREE;
5594         }
5595
5596       /* Set the debug information here, because this is the only
5597          place where we know the underlying type for a vector made
5598          with vector_size.  For debugging purposes we pretend a vector
5599          is an array within a structure.  */
5600       index = build_int_2 (TYPE_VECTOR_SUBPARTS (new_type) - 1, 0);
5601       array = build_array_type (type, build_index_type (index));
5602       rt = make_node (RECORD_TYPE);
5603
5604       TYPE_FIELDS (rt) = build_decl (FIELD_DECL, get_identifier ("f"), array);
5605       DECL_CONTEXT (TYPE_FIELDS (rt)) = rt;
5606       layout_type (rt);
5607       TYPE_DEBUG_REPRESENTATION_TYPE (new_type) = rt;
5608
5609       list_node = build_tree_list (NULL, new_type);
5610       TREE_CHAIN (list_node) = vector_type_node_list;
5611       vector_type_node_list = list_node;
5612     }
5613
5614   /* Build back pointers if needed.  */
5615   *node = vector_size_helper (*node, new_type);
5616
5617   return NULL_TREE;
5618 }
5619
5620 /* HACK.  GROSS.  This is absolutely disgusting.  I wish there was a
5621    better way.
5622
5623    If we requested a pointer to a vector, build up the pointers that
5624    we stripped off while looking for the inner type.  Similarly for
5625    return values from functions.
5626
5627    The argument "type" is the top of the chain, and "bottom" is the
5628    new type which we will point to.  */
5629
5630 static tree
5631 vector_size_helper (type, bottom)
5632      tree type, bottom;
5633 {
5634   tree inner, outer;
5635
5636   if (POINTER_TYPE_P (type))
5637     {
5638       inner = vector_size_helper (TREE_TYPE (type), bottom);
5639       outer = build_pointer_type (inner);
5640     }
5641   else if (TREE_CODE (type) == ARRAY_TYPE)
5642     {
5643       inner = vector_size_helper (TREE_TYPE (type), bottom);
5644       outer = build_array_type (inner, TYPE_VALUES (type));
5645     }
5646   else if (TREE_CODE (type) == FUNCTION_TYPE)
5647     {
5648       inner = vector_size_helper (TREE_TYPE (type), bottom);
5649       outer = build_function_type (inner, TYPE_VALUES (type));
5650     }
5651   else
5652     return bottom;
5653
5654   TREE_READONLY (outer) = TREE_READONLY (type);
5655   TREE_THIS_VOLATILE (outer) = TREE_THIS_VOLATILE (type);
5656
5657   return outer;
5658 }
5659
5660 /* Handle the "nonnull" attribute.  */
5661 static tree
5662 handle_nonnull_attribute (node, name, args, flags, no_add_attrs)
5663      tree *node;
5664      tree name ATTRIBUTE_UNUSED;
5665      tree args;
5666      int flags ATTRIBUTE_UNUSED;
5667      bool *no_add_attrs;
5668 {
5669   tree type = *node;
5670   unsigned HOST_WIDE_INT attr_arg_num;
5671
5672   /* If no arguments are specified, all pointer arguments should be
5673      non-null.  Veryify a full prototype is given so that the arguments
5674      will have the correct types when we actually check them later.  */
5675   if (! args)
5676     {
5677       if (! TYPE_ARG_TYPES (type))
5678         {
5679           error ("nonnull attribute without arguments on a non-prototype");
5680           *no_add_attrs = true;
5681         }
5682       return NULL_TREE;
5683     }
5684
5685   /* Argument list specified.  Verify that each argument number references
5686      a pointer argument.  */
5687   for (attr_arg_num = 1; args; args = TREE_CHAIN (args))
5688     {
5689       tree argument;
5690       unsigned HOST_WIDE_INT arg_num, ck_num;
5691
5692       if (! get_nonnull_operand (TREE_VALUE (args), &arg_num))
5693         {
5694           error ("nonnull argument has invalid operand number (arg %lu)",
5695                  (unsigned long) attr_arg_num);
5696           *no_add_attrs = true;
5697           return NULL_TREE;
5698         }
5699
5700       argument = TYPE_ARG_TYPES (type);
5701       if (argument)
5702         {
5703           for (ck_num = 1; ; ck_num++)
5704             {
5705               if (! argument || ck_num == arg_num)
5706                 break;
5707               argument = TREE_CHAIN (argument);
5708             }
5709
5710           if (! argument
5711               || TREE_CODE (TREE_VALUE (argument)) == VOID_TYPE)
5712             {
5713               error ("nonnull argument with out-of-range operand number (arg %lu, operand %lu)",
5714                      (unsigned long) attr_arg_num, (unsigned long) arg_num);
5715               *no_add_attrs = true;
5716               return NULL_TREE;
5717             }
5718
5719           if (TREE_CODE (TREE_VALUE (argument)) != POINTER_TYPE)
5720             {
5721               error ("nonnull argument references non-pointer operand (arg %lu, operand %lu)",
5722                    (unsigned long) attr_arg_num, (unsigned long) arg_num);
5723               *no_add_attrs = true;
5724               return NULL_TREE;
5725             }
5726         }
5727     }
5728
5729   return NULL_TREE;
5730 }
5731
5732 /* Check the argument list of a function call for null in argument slots
5733    that are marked as requiring a non-null pointer argument.  */
5734
5735 static void
5736 check_function_nonnull (attrs, params)
5737      tree attrs;
5738      tree params;
5739 {
5740   tree a, args, param;
5741   int param_num;
5742
5743   for (a = attrs; a; a = TREE_CHAIN (a))
5744     {
5745       if (is_attribute_p ("nonnull", TREE_PURPOSE (a)))
5746         {
5747           args = TREE_VALUE (a);
5748
5749           /* Walk the argument list.  If we encounter an argument number we
5750              should check for non-null, do it.  If the attribute has no args,
5751              then every pointer argument is checked (in which case the check
5752              for pointer type is done in check_nonnull_arg).  */
5753           for (param = params, param_num = 1; ;
5754                param_num++, param = TREE_CHAIN (param))
5755             {
5756               if (! param)
5757                 break;
5758               if (! args || nonnull_check_p (args, param_num))
5759                 check_function_arguments_recurse (check_nonnull_arg, NULL,
5760                                                   TREE_VALUE (param),
5761                                                   param_num);
5762             }
5763         }
5764     }
5765 }
5766
5767 /* Helper for check_function_nonnull; given a list of operands which
5768    must be non-null in ARGS, determine if operand PARAM_NUM should be
5769    checked.  */
5770
5771 static bool
5772 nonnull_check_p (args, param_num)
5773      tree args;
5774      unsigned HOST_WIDE_INT param_num;
5775 {
5776   unsigned HOST_WIDE_INT arg_num;
5777
5778   for (; args; args = TREE_CHAIN (args))
5779     {
5780       if (! get_nonnull_operand (TREE_VALUE (args), &arg_num))
5781         abort ();
5782
5783       if (arg_num == param_num)
5784         return true;
5785     }
5786   return false;
5787 }
5788
5789 /* Check that the function argument PARAM (which is operand number
5790    PARAM_NUM) is non-null.  This is called by check_function_nonnull
5791    via check_function_arguments_recurse.  */
5792
5793 static void
5794 check_nonnull_arg (ctx, param, param_num)
5795      void *ctx ATTRIBUTE_UNUSED;
5796      tree param;
5797      unsigned HOST_WIDE_INT param_num;
5798 {
5799   /* Just skip checking the argument if it's not a pointer.  This can
5800      happen if the "nonnull" attribute was given without an operand
5801      list (which means to check every pointer argument).  */
5802
5803   if (TREE_CODE (TREE_TYPE (param)) != POINTER_TYPE)
5804     return;
5805
5806   if (integer_zerop (param))
5807     warning ("null argument where non-null required (arg %lu)",
5808              (unsigned long) param_num);
5809 }
5810
5811 /* Helper for nonnull attribute handling; fetch the operand number
5812    from the attribute argument list.  */
5813
5814 static bool
5815 get_nonnull_operand (arg_num_expr, valp)
5816      tree arg_num_expr;
5817      unsigned HOST_WIDE_INT *valp;
5818 {
5819   /* Strip any conversions from the arg number and verify they
5820      are constants.  */
5821   while (TREE_CODE (arg_num_expr) == NOP_EXPR
5822          || TREE_CODE (arg_num_expr) == CONVERT_EXPR
5823          || TREE_CODE (arg_num_expr) == NON_LVALUE_EXPR)
5824     arg_num_expr = TREE_OPERAND (arg_num_expr, 0);
5825
5826   if (TREE_CODE (arg_num_expr) != INTEGER_CST
5827       || TREE_INT_CST_HIGH (arg_num_expr) != 0)
5828     return false;
5829
5830   *valp = TREE_INT_CST_LOW (arg_num_expr);
5831   return true;
5832 }
5833
5834 /* Handle a "nothrow" attribute; arguments as in
5835    struct attribute_spec.handler.  */
5836
5837 static tree
5838 handle_nothrow_attribute (node, name, args, flags, no_add_attrs)
5839      tree *node;
5840      tree name;
5841      tree args ATTRIBUTE_UNUSED;
5842      int flags ATTRIBUTE_UNUSED;
5843      bool *no_add_attrs;
5844 {
5845   if (TREE_CODE (*node) == FUNCTION_DECL)
5846     TREE_NOTHROW (*node) = 1;
5847   /* ??? TODO: Support types.  */
5848   else
5849     {
5850       warning ("`%s' attribute ignored", IDENTIFIER_POINTER (name));
5851       *no_add_attrs = true;
5852     }
5853
5854   return NULL_TREE;
5855 }
5856 \f
5857 /* Check for valid arguments being passed to a function.  */
5858 void
5859 check_function_arguments (attrs, params)
5860      tree attrs;
5861      tree params;
5862 {
5863   /* Check for null being passed in a pointer argument that must be
5864      non-null.  We also need to do this if format checking is enabled.  */
5865
5866   if (warn_nonnull)
5867     check_function_nonnull (attrs, params);
5868
5869   /* Check for errors in format strings.  */
5870
5871   if (warn_format)
5872     check_function_format (NULL, attrs, params);
5873 }
5874
5875 /* Generic argument checking recursion routine.  PARAM is the argument to
5876    be checked.  PARAM_NUM is the number of the argument.  CALLBACK is invoked
5877    once the argument is resolved.  CTX is context for the callback.  */
5878 void
5879 check_function_arguments_recurse (callback, ctx, param, param_num)
5880      void (*callback) PARAMS ((void *, tree, unsigned HOST_WIDE_INT));
5881      void *ctx;
5882      tree param;
5883      unsigned HOST_WIDE_INT param_num;
5884 {
5885   if (TREE_CODE (param) == NOP_EXPR)
5886     {
5887       /* Strip coercion.  */
5888       check_function_arguments_recurse (callback, ctx,
5889                                         TREE_OPERAND (param, 0), param_num);
5890       return;
5891     }
5892
5893   if (TREE_CODE (param) == CALL_EXPR)
5894     {
5895       tree type = TREE_TYPE (TREE_TYPE (TREE_OPERAND (param, 0)));
5896       tree attrs;
5897       bool found_format_arg = false;
5898
5899       /* See if this is a call to a known internationalization function
5900          that modifies a format arg.  Such a function may have multiple
5901          format_arg attributes (for example, ngettext).  */
5902
5903       for (attrs = TYPE_ATTRIBUTES (type);
5904            attrs;
5905            attrs = TREE_CHAIN (attrs))
5906         if (is_attribute_p ("format_arg", TREE_PURPOSE (attrs)))
5907           {
5908             tree inner_args;
5909             tree format_num_expr;
5910             int format_num;
5911             int i;
5912
5913             /* Extract the argument number, which was previously checked
5914                to be valid.  */
5915             format_num_expr = TREE_VALUE (TREE_VALUE (attrs));
5916             while (TREE_CODE (format_num_expr) == NOP_EXPR
5917                    || TREE_CODE (format_num_expr) == CONVERT_EXPR
5918                    || TREE_CODE (format_num_expr) == NON_LVALUE_EXPR)
5919               format_num_expr = TREE_OPERAND (format_num_expr, 0);
5920
5921             if (TREE_CODE (format_num_expr) != INTEGER_CST
5922                 || TREE_INT_CST_HIGH (format_num_expr) != 0)
5923               abort ();
5924
5925             format_num = TREE_INT_CST_LOW (format_num_expr);
5926
5927             for (inner_args = TREE_OPERAND (param, 1), i = 1;
5928                  inner_args != 0;
5929                  inner_args = TREE_CHAIN (inner_args), i++)
5930               if (i == format_num)
5931                 {
5932                   check_function_arguments_recurse (callback, ctx,
5933                                                     TREE_VALUE (inner_args),
5934                                                     param_num);
5935                   found_format_arg = true;
5936                   break;
5937                 }
5938           }
5939
5940       /* If we found a format_arg attribute and did a recursive check,
5941          we are done with checking this argument.  Otherwise, we continue
5942          and this will be considered a non-literal.  */
5943       if (found_format_arg)
5944         return;
5945     }
5946
5947   if (TREE_CODE (param) == COND_EXPR)
5948     {
5949       /* Check both halves of the conditional expression.  */
5950       check_function_arguments_recurse (callback, ctx,
5951                                         TREE_OPERAND (param, 1), param_num);
5952       check_function_arguments_recurse (callback, ctx,
5953                                         TREE_OPERAND (param, 2), param_num);
5954       return;
5955     }
5956
5957   (*callback) (ctx, param, param_num);
5958 }
5959
5960 #include "gt-c-common.h"