contrib/gcc-4.1/gcc/c-pragma.c

   1 /* Handle #pragma, system V.4 style.  Supports #pragma weak and #pragma pack.
   2    Copyright (C) 1992, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005
   3    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, 51 Franklin Street, Fifth Floor, Boston, MA
  20 02110-1301, USA.  */
  21
  22 #include "config.h"
  23 #include "system.h"
  24 #include "coretypes.h"
  25 #include "tm.h"
  26 #include "rtl.h"
  27 #include "tree.h"
  28 #include "function.h"
  29 #include "cpplib.h"
  30 #include "c-pragma.h"
  31 #include "flags.h"
  32 #include "toplev.h"
  33 #include "ggc.h"
  34 #include "c-common.h"
  35 #include "output.h"
  36 #include "tm_p.h"
  37 #include "vec.h"
  38 #include "target.h"
  39
  40 #define GCC_BAD(gmsgid) \
  41   do { warning (OPT_Wpragmas, gmsgid); return; } while (0)
  42 #define GCC_BAD2(gmsgid, arg) \
  43   do { warning (OPT_Wpragmas, gmsgid, arg); return; } while (0)
  44
  45 typedef struct align_stack GTY(())
  46 {
  47   int                  alignment;
  48   tree                 id;
  49   struct align_stack * prev;
  50 } align_stack;
  51
  52 static GTY(()) struct align_stack * alignment_stack;
  53
  54 #ifdef HANDLE_PRAGMA_PACK
  55 static void handle_pragma_pack (cpp_reader *);
  56
  57 #ifdef HANDLE_PRAGMA_PACK_PUSH_POP
  58 /* If we have a "global" #pragma pack(<n>) in effect when the first
  59    #pragma pack(push,<n>) is encountered, this stores the value of
  60    maximum_field_alignment in effect.  When the final pop_alignment()
  61    happens, we restore the value to this, not to a value of 0 for
  62    maximum_field_alignment.  Value is in bits.  */
  63 static int default_alignment;
  64 #define SET_GLOBAL_ALIGNMENT(ALIGN) (maximum_field_alignment = *(alignment_stack == NULL \
  65         ? &default_alignment \
  66         : &alignment_stack->alignment) = (ALIGN))
  67
  68 static void push_alignment (int, tree);
  69 static void pop_alignment (tree);
  70
  71 /* Push an alignment value onto the stack.  */
  72 static void
  73 push_alignment (int alignment, tree id)
  74 {
  75   align_stack * entry;
  76
  77   entry = ggc_alloc (sizeof (* entry));
  78
  79   entry->alignment  = alignment;
  80   entry->id         = id;
  81   entry->prev       = alignment_stack;
  82
  83   /* The current value of maximum_field_alignment is not necessarily
  84      0 since there may be a #pragma pack(<n>) in effect; remember it
  85      so that we can restore it after the final #pragma pop().  */
  86   if (alignment_stack == NULL)
  87     default_alignment = maximum_field_alignment;
  88
  89   alignment_stack = entry;
  90
  91   maximum_field_alignment = alignment;
  92 }
  93
  94 /* Undo a push of an alignment onto the stack.  */
  95 static void
  96 pop_alignment (tree id)
  97 {
  98   align_stack * entry;
  99
 100   if (alignment_stack == NULL)
 101     GCC_BAD ("#pragma pack (pop) encountered without matching #pragma pack (push)");
 102
 103   /* If we got an identifier, strip away everything above the target
 104      entry so that the next step will restore the state just below it.  */
 105   if (id)
 106     {
 107       for (entry = alignment_stack; entry; entry = entry->prev)
 108         if (entry->id == id)
 109           {
 110             alignment_stack = entry;
 111             break;
 112           }
 113       if (entry == NULL)
 114         warning (OPT_Wpragmas, "\
 115 #pragma pack(pop, %s) encountered without matching #pragma pack(push, %s)"
 116                  , IDENTIFIER_POINTER (id), IDENTIFIER_POINTER (id));
 117     }
 118
 119   entry = alignment_stack->prev;
 120
 121   maximum_field_alignment = entry ? entry->alignment : default_alignment;
 122
 123   alignment_stack = entry;
 124 }
 125 #else  /* not HANDLE_PRAGMA_PACK_PUSH_POP */
 126 #define SET_GLOBAL_ALIGNMENT(ALIGN) (maximum_field_alignment = (ALIGN))
 127 #define push_alignment(ID, N) \
 128     GCC_BAD ("#pragma pack(push[, id], <n>) is not supported on this target")
 129 #define pop_alignment(ID) \
 130     GCC_BAD ("#pragma pack(pop[, id], <n>) is not supported on this target")
 131 #endif /* HANDLE_PRAGMA_PACK_PUSH_POP */
 132
 133 /* #pragma pack ()
 134    #pragma pack (N)
 135
 136    #pragma pack (push)
 137    #pragma pack (push, N)
 138    #pragma pack (push, ID)
 139    #pragma pack (push, ID, N)
 140    #pragma pack (pop)
 141    #pragma pack (pop, ID) */
 142 static void
 143 handle_pragma_pack (cpp_reader * ARG_UNUSED (dummy))
 144 {
 145   tree x, id = 0;
 146   int align = -1;
 147   enum cpp_ttype token;
 148   enum { set, push, pop } action;
 149
 150   if (c_lex (&x) != CPP_OPEN_PAREN)
 151     GCC_BAD ("missing %<(%> after %<#pragma pack%> - ignored");
 152
 153   token = c_lex (&x);
 154   if (token == CPP_CLOSE_PAREN)
 155     {
 156       action = set;
 157       align = initial_max_fld_align;
 158     }
 159   else if (token == CPP_NUMBER)
 160     {
 161       if (TREE_CODE (x) != INTEGER_CST)
 162         GCC_BAD ("invalid constant in %<#pragma pack%> - ignored");
 163       align = TREE_INT_CST_LOW (x);
 164       action = set;
 165       if (c_lex (&x) != CPP_CLOSE_PAREN)
 166         GCC_BAD ("malformed %<#pragma pack%> - ignored");
 167     }
 168   else if (token == CPP_NAME)
 169     {
 170 #define GCC_BAD_ACTION do { if (action != pop) \
 171           GCC_BAD ("malformed %<#pragma pack(push[, id][, <n>])%> - ignored"); \
 172         else \
 173           GCC_BAD ("malformed %<#pragma pack(pop[, id])%> - ignored"); \
 174         } while (0)
 175
 176       const char *op = IDENTIFIER_POINTER (x);
 177       if (!strcmp (op, "push"))
 178         action = push;
 179       else if (!strcmp (op, "pop"))
 180         action = pop;
 181       else
 182         GCC_BAD2 ("unknown action %qs for %<#pragma pack%> - ignored", op);
 183
 184       while ((token = c_lex (&x)) == CPP_COMMA)
 185         {
 186           token = c_lex (&x);
 187           if (token == CPP_NAME && id == 0)
 188             {
 189               id = x;
 190             }
 191           else if (token == CPP_NUMBER && action == push && align == -1)
 192             {
 193               if (TREE_CODE (x) != INTEGER_CST)
 194                 GCC_BAD ("invalid constant in %<#pragma pack%> - ignored");
 195               align = TREE_INT_CST_LOW (x);
 196               if (align == -1)
 197                 action = set;
 198             }
 199           else
 200             GCC_BAD_ACTION;
 201         }
 202
 203       if (token != CPP_CLOSE_PAREN)
 204         GCC_BAD_ACTION;
 205 #undef GCC_BAD_ACTION
 206     }
 207   else
 208     GCC_BAD ("malformed %<#pragma pack%> - ignored");
 209
 210   if (c_lex (&x) != CPP_EOF)
 211     warning (OPT_Wpragmas, "junk at end of %<#pragma pack%>");
 212
 213   if (flag_pack_struct)
 214     GCC_BAD ("#pragma pack has no effect with -fpack-struct - ignored");
 215
 216   if (action != pop)
 217     switch (align)
 218       {
 219       case 0:
 220       case 1:
 221       case 2:
 222       case 4:
 223       case 8:
 224       case 16:
 225         align *= BITS_PER_UNIT;
 226         break;
 227       case -1:
 228         if (action == push)
 229           {
 230             align = maximum_field_alignment;
 231             break;
 232           }
 233       default:
 234         GCC_BAD2 ("alignment must be a small power of two, not %d", align);
 235       }
 236
 237   switch (action)
 238     {
 239     case set:   SET_GLOBAL_ALIGNMENT (align);  break;
 240     case push:  push_alignment (align, id);    break;
 241     case pop:   pop_alignment (id);            break;
 242     }
 243 }
 244 #endif  /* HANDLE_PRAGMA_PACK */
 245
 246 static GTY(()) tree pending_weaks;
 247
 248 #ifdef HANDLE_PRAGMA_WEAK
 249 static void apply_pragma_weak (tree, tree);
 250 static void handle_pragma_weak (cpp_reader *);
 251
 252 static void
 253 apply_pragma_weak (tree decl, tree value)
 254 {
 255   if (value)
 256     {
 257       value = build_string (IDENTIFIER_LENGTH (value),
 258                             IDENTIFIER_POINTER (value));
 259       decl_attributes (&decl, build_tree_list (get_identifier ("alias"),
 260                                                build_tree_list (NULL, value)),
 261                        0);
 262     }
 263
 264   if (SUPPORTS_WEAK && DECL_EXTERNAL (decl) && TREE_USED (decl)
 265       && !DECL_WEAK (decl) /* Don't complain about a redundant #pragma.  */
 266       && TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl)))
 267     warning (OPT_Wpragmas, "applying #pragma weak %q+D after first use "
 268              "results in unspecified behavior", decl);
 269
 270   declare_weak (decl);
 271 }
 272
 273 void
 274 maybe_apply_pragma_weak (tree decl)
 275 {
 276   tree *p, t, id;
 277
 278   /* Avoid asking for DECL_ASSEMBLER_NAME when it's not needed.  */
 279
 280   /* No weak symbols pending, take the short-cut.  */
 281   if (!pending_weaks)
 282     return;
 283   /* If it's not visible outside this file, it doesn't matter whether
 284      it's weak.  */
 285   if (!DECL_EXTERNAL (decl) && !TREE_PUBLIC (decl))
 286     return;
 287   /* If it's not a function or a variable, it can't be weak.
 288      FIXME: what kinds of things are visible outside this file but
 289      aren't functions or variables?   Should this be an assert instead?  */
 290   if (TREE_CODE (decl) != FUNCTION_DECL && TREE_CODE (decl) != VAR_DECL)
 291     return;
 292
 293   id = DECL_ASSEMBLER_NAME (decl);
 294
 295   for (p = &pending_weaks; (t = *p) ; p = &TREE_CHAIN (t))
 296     if (id == TREE_PURPOSE (t))
 297       {
 298         apply_pragma_weak (decl, TREE_VALUE (t));
 299         *p = TREE_CHAIN (t);
 300         break;
 301       }
 302 }
 303
 304 /* Process all "#pragma weak A = B" directives where we have not seen
 305    a decl for A.  */
 306 void
 307 maybe_apply_pending_pragma_weaks (void)
 308 {
 309   tree *p, t, alias_id, id, decl, *next;
 310
 311   for (p = &pending_weaks; (t = *p) ; p = next)
 312     {
 313       next = &TREE_CHAIN (t);
 314       alias_id = TREE_PURPOSE (t);
 315       id = TREE_VALUE (t);
 316
 317       if (TREE_VALUE (t) == NULL)
 318         continue;
 319
 320       decl = build_decl (FUNCTION_DECL, alias_id, default_function_type);
 321
 322       DECL_ARTIFICIAL (decl) = 1;
 323       TREE_PUBLIC (decl) = 1;
 324       DECL_EXTERNAL (decl) = 1;
 325       DECL_WEAK (decl) = 1;
 326
 327       assemble_alias (decl, id);
 328     }
 329 }
 330
 331 /* #pragma weak name [= value] */
 332 static void
 333 handle_pragma_weak (cpp_reader * ARG_UNUSED (dummy))
 334 {
 335   tree name, value, x, decl;
 336   enum cpp_ttype t;
 337
 338   value = 0;
 339
 340   if (c_lex (&name) != CPP_NAME)
 341     GCC_BAD ("malformed #pragma weak, ignored");
 342   t = c_lex (&x);
 343   if (t == CPP_EQ)
 344     {
 345       if (c_lex (&value) != CPP_NAME)
 346         GCC_BAD ("malformed #pragma weak, ignored");
 347       t = c_lex (&x);
 348     }
 349   if (t != CPP_EOF)
 350     warning (OPT_Wpragmas, "junk at end of #pragma weak");
 351
 352   decl = identifier_global_value (name);
 353   if (decl && DECL_P (decl))
 354     {
 355       apply_pragma_weak (decl, value);
 356       if (value)
 357         assemble_alias (decl, value);
 358     }
 359   else
 360     pending_weaks = tree_cons (name, value, pending_weaks);
 361 }
 362 #else
 363 void
 364 maybe_apply_pragma_weak (tree ARG_UNUSED (decl))
 365 {
 366 }
 367
 368 void
 369 maybe_apply_pending_pragma_weaks (void)
 370 {
 371 }
 372 #endif /* HANDLE_PRAGMA_WEAK */
 373
 374 /* GCC supports two #pragma directives for renaming the external
 375    symbol associated with a declaration (DECL_ASSEMBLER_NAME), for
 376    compatibility with the Solaris and Tru64 system headers.  GCC also
 377    has its own notation for this, __asm__("name") annotations.
 378
 379    Corner cases of these features and their interaction:
 380
 381    1) Both pragmas silently apply only to declarations with external
 382       linkage (that is, TREE_PUBLIC || DECL_EXTERNAL).  Asm labels
 383       do not have this restriction.
 384
 385    2) In C++, both #pragmas silently apply only to extern "C" declarations.
 386       Asm labels do not have this restriction.
 387
 388    3) If any of the three ways of changing DECL_ASSEMBLER_NAME is
 389       applied to a decl whose DECL_ASSEMBLER_NAME is already set, and the
 390       new name is different, a warning issues and the name does not change.
 391
 392    4) The "source name" for #pragma redefine_extname is the DECL_NAME,
 393       *not* the DECL_ASSEMBLER_NAME.
 394
 395    5) If #pragma extern_prefix is in effect and a declaration occurs
 396       with an __asm__ name, the #pragma extern_prefix is silently
 397       ignored for that declaration.
 398
 399    6) If #pragma extern_prefix and #pragma redefine_extname apply to
 400       the same declaration, whichever triggered first wins, and a warning
 401       is issued.  (We would like to have #pragma redefine_extname always
 402       win, but it can appear either before or after the declaration, and
 403       if it appears afterward, we have no way of knowing whether a modified
 404       DECL_ASSEMBLER_NAME is due to #pragma extern_prefix.)  */
 405
 406 static GTY(()) tree pending_redefine_extname;
 407
 408 static void handle_pragma_redefine_extname (cpp_reader *);
 409
 410 /* #pragma redefine_extname oldname newname */
 411 static void
 412 handle_pragma_redefine_extname (cpp_reader * ARG_UNUSED (dummy))
 413 {
 414   tree oldname, newname, decl, x;
 415   enum cpp_ttype t;
 416
 417   if (c_lex (&oldname) != CPP_NAME)
 418     GCC_BAD ("malformed #pragma redefine_extname, ignored");
 419   if (c_lex (&newname) != CPP_NAME)
 420     GCC_BAD ("malformed #pragma redefine_extname, ignored");
 421   t = c_lex (&x);
 422   if (t != CPP_EOF)
 423     warning (OPT_Wpragmas, "junk at end of #pragma redefine_extname");
 424
 425   if (!flag_mudflap && !targetm.handle_pragma_redefine_extname)
 426     {
 427       if (warn_unknown_pragmas > in_system_header)
 428         warning (OPT_Wunknown_pragmas,
 429                  "#pragma redefine_extname not supported on this target");
 430       return;
 431     }
 432
 433   decl = identifier_global_value (oldname);
 434   if (decl
 435       && (TREE_PUBLIC (decl) || DECL_EXTERNAL (decl))
 436       && (TREE_CODE (decl) == FUNCTION_DECL
 437           || TREE_CODE (decl) == VAR_DECL)
 438       && has_c_linkage (decl))
 439     {
 440       if (DECL_ASSEMBLER_NAME_SET_P (decl))
 441         {
 442           const char *name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
 443           name = targetm.strip_name_encoding (name);
 444
 445           if (strcmp (name, IDENTIFIER_POINTER (newname)))
 446             warning (OPT_Wpragmas, "#pragma redefine_extname ignored due to "
 447                      "conflict with previous rename");
 448         }
 449       else
 450         change_decl_assembler_name (decl, newname);
 451     }
 452   else
 453     /* We have to add this to the rename list even if there's already
 454        a global value that doesn't meet the above criteria, because in
 455        C++ "struct foo {...};" puts "foo" in the current namespace but
 456        does *not* conflict with a subsequent declaration of a function
 457        or variable foo.  See g++.dg/other/pragma-re-2.C.  */
 458     add_to_renaming_pragma_list (oldname, newname);
 459 }
 460
 461 /* This is called from here and from ia64.c.  */
 462 void
 463 add_to_renaming_pragma_list (tree oldname, tree newname)
 464 {
 465   tree previous = purpose_member (oldname, pending_redefine_extname);
 466   if (previous)
 467     {
 468       if (TREE_VALUE (previous) != newname)
 469         warning (OPT_Wpragmas, "#pragma redefine_extname ignored due to "
 470                  "conflict with previous #pragma redefine_extname");
 471       return;
 472     }
 473
 474   pending_redefine_extname
 475     = tree_cons (oldname, newname, pending_redefine_extname);
 476 }
 477
 478 static GTY(()) tree pragma_extern_prefix;
 479
 480 /* #pragma extern_prefix "prefix" */
 481 static void
 482 handle_pragma_extern_prefix (cpp_reader * ARG_UNUSED (dummy))
 483 {
 484   tree prefix, x;
 485   enum cpp_ttype t;
 486
 487   if (c_lex (&prefix) != CPP_STRING)
 488     GCC_BAD ("malformed #pragma extern_prefix, ignored");
 489   t = c_lex (&x);
 490   if (t != CPP_EOF)
 491     warning (OPT_Wpragmas, "junk at end of #pragma extern_prefix");
 492
 493   if (targetm.handle_pragma_extern_prefix)
 494     /* Note that the length includes the null terminator.  */
 495     pragma_extern_prefix = (TREE_STRING_LENGTH (prefix) > 1 ? prefix : NULL);
 496   else if (warn_unknown_pragmas > in_system_header)
 497     warning (OPT_Wunknown_pragmas,
 498              "#pragma extern_prefix not supported on this target");
 499 }
 500
 501 /* Hook from the front ends to apply the results of one of the preceding
 502    pragmas that rename variables.  */
 503
 504 tree
 505 maybe_apply_renaming_pragma (tree decl, tree asmname)
 506 {
 507   tree *p, t;
 508
 509   /* The renaming pragmas are only applied to declarations with
 510      external linkage.  */
 511   if ((TREE_CODE (decl) != FUNCTION_DECL && TREE_CODE (decl) != VAR_DECL)
 512       || (!TREE_PUBLIC (decl) && !DECL_EXTERNAL (decl))
 513       || !has_c_linkage (decl))
 514     return asmname;
 515
 516   /* If the DECL_ASSEMBLER_NAME is already set, it does not change,
 517      but we may warn about a rename that conflicts.  */
 518   if (DECL_ASSEMBLER_NAME_SET_P (decl))
 519     {
 520       const char *oldname = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
 521       oldname = targetm.strip_name_encoding (oldname);
 522
 523       if (asmname && strcmp (TREE_STRING_POINTER (asmname), oldname))
 524           warning (OPT_Wpragmas, "asm declaration ignored due to "
 525                    "conflict with previous rename");
 526
 527       /* Take any pending redefine_extname off the list.  */
 528       for (p = &pending_redefine_extname; (t = *p); p = &TREE_CHAIN (t))
 529         if (DECL_NAME (decl) == TREE_PURPOSE (t))
 530           {
 531             /* Only warn if there is a conflict.  */
 532             if (strcmp (IDENTIFIER_POINTER (TREE_VALUE (t)), oldname))
 533               warning (OPT_Wpragmas, "#pragma redefine_extname ignored due to "
 534                        "conflict with previous rename");
 535
 536             *p = TREE_CHAIN (t);
 537             break;
 538           }
 539       return 0;
 540     }
 541
 542   /* Find out if we have a pending #pragma redefine_extname.  */
 543   for (p = &pending_redefine_extname; (t = *p); p = &TREE_CHAIN (t))
 544     if (DECL_NAME (decl) == TREE_PURPOSE (t))
 545       {
 546         tree newname = TREE_VALUE (t);
 547         *p = TREE_CHAIN (t);
 548
 549         /* If we already have an asmname, #pragma redefine_extname is
 550            ignored (with a warning if it conflicts).  */
 551         if (asmname)
 552           {
 553             if (strcmp (TREE_STRING_POINTER (asmname),
 554                         IDENTIFIER_POINTER (newname)) != 0)
 555               warning (OPT_Wpragmas, "#pragma redefine_extname ignored due to "
 556                        "conflict with __asm__ declaration");
 557             return asmname;
 558           }
 559
 560         /* Otherwise we use what we've got; #pragma extern_prefix is
 561            silently ignored.  */
 562         return build_string (IDENTIFIER_LENGTH (newname),
 563                              IDENTIFIER_POINTER (newname));
 564       }
 565
 566   /* If we've got an asmname, #pragma extern_prefix is silently ignored.  */
 567   if (asmname)
 568     return asmname;
 569
 570   /* If #pragma extern_prefix is in effect, apply it.  */
 571   if (pragma_extern_prefix)
 572     {
 573       const char *prefix = TREE_STRING_POINTER (pragma_extern_prefix);
 574       size_t plen = TREE_STRING_LENGTH (pragma_extern_prefix) - 1;
 575
 576       const char *id = IDENTIFIER_POINTER (DECL_NAME (decl));
 577       size_t ilen = IDENTIFIER_LENGTH (DECL_NAME (decl));
 578
 579       char *newname = (char *) alloca (plen + ilen + 1);
 580
 581       memcpy (newname,        prefix, plen);
 582       memcpy (newname + plen, id, ilen + 1);
 583
 584       return build_string (plen + ilen, newname);
 585     }
 586
 587   /* Nada.  */
 588   return 0;
 589 }
 590
 591
 592 #ifdef HANDLE_PRAGMA_VISIBILITY
 593 static void handle_pragma_visibility (cpp_reader *);
 594
 595 typedef enum symbol_visibility visibility;
 596 DEF_VEC_I (visibility);
 597 DEF_VEC_ALLOC_I (visibility, heap);
 598
 599 /* Sets the default visibility for symbols to something other than that
 600    specified on the command line.  */
 601 static void
 602 handle_pragma_visibility (cpp_reader *dummy ATTRIBUTE_UNUSED)
 603 {
 604   /* Form is #pragma GCC visibility push(hidden)|pop */
 605   tree x;
 606   enum cpp_ttype token;
 607   enum { bad, push, pop } action = bad;
 608   static VEC (visibility, heap) *visstack;
 609
 610   token = c_lex (&x);
 611   if (token == CPP_NAME)
 612     {
 613       const char *op = IDENTIFIER_POINTER (x);
 614       if (!strcmp (op, "push"))
 615         action = push;
 616       else if (!strcmp (op, "pop"))
 617         action = pop;
 618     }
 619   if (bad == action)
 620     GCC_BAD ("#pragma GCC visibility must be followed by push or pop");
 621   else
 622     {
 623       if (pop == action)
 624         {
 625           if (!VEC_length (visibility, visstack))
 626             {
 627               GCC_BAD ("no matching push for %<#pragma GCC visibility pop%>");
 628             }
 629           else
 630             {
 631               default_visibility = VEC_pop (visibility, visstack);
 632               visibility_options.inpragma
 633                 = VEC_length (visibility, visstack) != 0;
 634             }
 635         }
 636       else
 637         {
 638           if (c_lex (&x) != CPP_OPEN_PAREN)
 639             GCC_BAD ("missing %<(%> after %<#pragma GCC visibility push%> - ignored");
 640           token = c_lex (&x);
 641           if (token != CPP_NAME)
 642             {
 643               GCC_BAD ("malformed #pragma GCC visibility push");
 644             }
 645           else
 646             {
 647               const char *str = IDENTIFIER_POINTER (x);
 648               VEC_safe_push (visibility, heap, visstack,
 649                              default_visibility);
 650               if (!strcmp (str, "default"))
 651                 default_visibility = VISIBILITY_DEFAULT;
 652               else if (!strcmp (str, "internal"))
 653                 default_visibility = VISIBILITY_INTERNAL;
 654               else if (!strcmp (str, "hidden"))
 655                 default_visibility = VISIBILITY_HIDDEN;
 656               else if (!strcmp (str, "protected"))
 657                 default_visibility = VISIBILITY_PROTECTED;
 658               else
 659                 {
 660                   GCC_BAD ("#pragma GCC visibility push() must specify default, internal, hidden or protected");
 661                 }
 662               visibility_options.inpragma = 1;
 663             }
 664           if (c_lex (&x) != CPP_CLOSE_PAREN)
 665             GCC_BAD ("missing %<(%> after %<#pragma GCC visibility push%> - ignored");
 666         }
 667     }
 668   if (c_lex (&x) != CPP_EOF)
 669     warning (OPT_Wpragmas, "junk at end of %<#pragma GCC visibility%>");
 670 }
 671
 672 #endif
 673
 674 /* Front-end wrappers for pragma registration to avoid dragging
 675    cpplib.h in almost everywhere.  */
 676 void
 677 c_register_pragma (const char *space, const char *name,
 678                    void (*handler) (struct cpp_reader *))
 679 {
 680   cpp_register_pragma (parse_in, space, name, handler, 0);
 681 }
 682
 683 void
 684 c_register_pragma_with_expansion (const char *space, const char *name,
 685                                   void (*handler) (struct cpp_reader *))
 686 {
 687   cpp_register_pragma (parse_in, space, name, handler, 1);
 688 }
 689
 690 /* Set up front-end pragmas.  */
 691 void
 692 init_pragma (void)
 693 {
 694 #ifdef HANDLE_PRAGMA_PACK
 695 #ifdef HANDLE_PRAGMA_PACK_WITH_EXPANSION
 696   c_register_pragma_with_expansion (0, "pack", handle_pragma_pack);
 697 #else
 698   c_register_pragma (0, "pack", handle_pragma_pack);
 699 #endif
 700 #endif
 701 #ifdef HANDLE_PRAGMA_WEAK
 702   c_register_pragma (0, "weak", handle_pragma_weak);
 703 #endif
 704 #ifdef HANDLE_PRAGMA_VISIBILITY
 705   c_register_pragma ("GCC", "visibility", handle_pragma_visibility);
 706 #endif
 707
 708   c_register_pragma (0, "redefine_extname", handle_pragma_redefine_extname);
 709   c_register_pragma (0, "extern_prefix", handle_pragma_extern_prefix);
 710
 711   c_register_pragma ("GCC", "pch_preprocess", c_common_pch_pragma);
 712
 713 #ifdef REGISTER_TARGET_PRAGMAS
 714   REGISTER_TARGET_PRAGMAS ();
 715 #endif
 716 }
 717
 718 #include "gt-c-pragma.h"