gcc/fortran/trans-decl.c

   1 /* Backend function setup
   2    Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007 Free Software
   3    Foundation, Inc.
   4    Contributed by Paul Brook
   5
   6 This file is part of GCC.
   7
   8 GCC is free software; you can redistribute it and/or modify it under
   9 the terms of the GNU General Public License as published by the Free
  10 Software Foundation; either version 3, or (at your option) any later
  11 version.
  12
  13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16 for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GCC; see the file COPYING3.  If not see
  20 <http://www.gnu.org/licenses/>.  */
  21
  22 /* trans-decl.c -- Handling of backend function and variable decls, etc */
  23
  24 #include "config.h"
  25 #include "system.h"
  26 #include "coretypes.h"
  27 #include "tree.h"
  28 #include "tree-dump.h"
  29 #include "tree-gimple.h"
  30 #include "ggc.h"
  31 #include "toplev.h"
  32 #include "tm.h"
  33 #include "rtl.h"
  34 #include "target.h"
  35 #include "function.h"
  36 #include "flags.h"
  37 #include "cgraph.h"
  38 #include "gfortran.h"
  39 #include "trans.h"
  40 #include "trans-types.h"
  41 #include "trans-array.h"
  42 #include "trans-const.h"
  43 /* Only for gfc_trans_code.  Shouldn't need to include this.  */
  44 #include "trans-stmt.h"
  45
  46 #define MAX_LABEL_VALUE 99999
  47
  48
  49 /* Holds the result of the function if no result variable specified.  */
  50
  51 static GTY(()) tree current_fake_result_decl;
  52 static GTY(()) tree parent_fake_result_decl;
  53
  54 static GTY(()) tree current_function_return_label;
  55
  56
  57 /* Holds the variable DECLs for the current function.  */
  58
  59 static GTY(()) tree saved_function_decls;
  60 static GTY(()) tree saved_parent_function_decls;
  61
  62
  63 /* The namespace of the module we're currently generating.  Only used while
  64    outputting decls for module variables.  Do not rely on this being set.  */
  65
  66 static gfc_namespace *module_namespace;
  67
  68
  69 /* List of static constructor functions.  */
  70
  71 tree gfc_static_ctors;
  72
  73
  74 /* Function declarations for builtin library functions.  */
  75
  76 tree gfor_fndecl_internal_realloc;
  77 tree gfor_fndecl_allocate;
  78 tree gfor_fndecl_allocate_array;
  79 tree gfor_fndecl_deallocate;
  80 tree gfor_fndecl_pause_numeric;
  81 tree gfor_fndecl_pause_string;
  82 tree gfor_fndecl_stop_numeric;
  83 tree gfor_fndecl_stop_string;
  84 tree gfor_fndecl_select_string;
  85 tree gfor_fndecl_runtime_error;
  86 tree gfor_fndecl_runtime_error_at;
  87 tree gfor_fndecl_os_error;
  88 tree gfor_fndecl_generate_error;
  89 tree gfor_fndecl_set_fpe;
  90 tree gfor_fndecl_set_options;
  91 tree gfor_fndecl_set_convert;
  92 tree gfor_fndecl_set_record_marker;
  93 tree gfor_fndecl_set_max_subrecord_length;
  94 tree gfor_fndecl_ctime;
  95 tree gfor_fndecl_fdate;
  96 tree gfor_fndecl_ttynam;
  97 tree gfor_fndecl_in_pack;
  98 tree gfor_fndecl_in_unpack;
  99 tree gfor_fndecl_associated;
 100
 101
 102 /* Math functions.  Many other math functions are handled in
 103    trans-intrinsic.c.  */
 104
 105 gfc_powdecl_list gfor_fndecl_math_powi[4][3];
 106 tree gfor_fndecl_math_cpowf;
 107 tree gfor_fndecl_math_cpow;
 108 tree gfor_fndecl_math_cpowl10;
 109 tree gfor_fndecl_math_cpowl16;
 110 tree gfor_fndecl_math_ishftc4;
 111 tree gfor_fndecl_math_ishftc8;
 112 tree gfor_fndecl_math_ishftc16;
 113 tree gfor_fndecl_math_exponent4;
 114 tree gfor_fndecl_math_exponent8;
 115 tree gfor_fndecl_math_exponent10;
 116 tree gfor_fndecl_math_exponent16;
 117
 118
 119 /* String functions.  */
 120
 121 tree gfor_fndecl_compare_string;
 122 tree gfor_fndecl_concat_string;
 123 tree gfor_fndecl_string_len_trim;
 124 tree gfor_fndecl_string_index;
 125 tree gfor_fndecl_string_scan;
 126 tree gfor_fndecl_string_verify;
 127 tree gfor_fndecl_string_trim;
 128 tree gfor_fndecl_string_minmax;
 129 tree gfor_fndecl_adjustl;
 130 tree gfor_fndecl_adjustr;
 131
 132
 133 /* Other misc. runtime library functions.  */
 134
 135 tree gfor_fndecl_size0;
 136 tree gfor_fndecl_size1;
 137 tree gfor_fndecl_iargc;
 138
 139 /* Intrinsic functions implemented in FORTRAN.  */
 140 tree gfor_fndecl_si_kind;
 141 tree gfor_fndecl_sr_kind;
 142
 143 /* BLAS gemm functions.  */
 144 tree gfor_fndecl_sgemm;
 145 tree gfor_fndecl_dgemm;
 146 tree gfor_fndecl_cgemm;
 147 tree gfor_fndecl_zgemm;
 148
 149
 150 static void
 151 gfc_add_decl_to_parent_function (tree decl)
 152 {
 153   gcc_assert (decl);
 154   DECL_CONTEXT (decl) = DECL_CONTEXT (current_function_decl);
 155   DECL_NONLOCAL (decl) = 1;
 156   TREE_CHAIN (decl) = saved_parent_function_decls;
 157   saved_parent_function_decls = decl;
 158 }
 159
 160 void
 161 gfc_add_decl_to_function (tree decl)
 162 {
 163   gcc_assert (decl);
 164   TREE_USED (decl) = 1;
 165   DECL_CONTEXT (decl) = current_function_decl;
 166   TREE_CHAIN (decl) = saved_function_decls;
 167   saved_function_decls = decl;
 168 }
 169
 170
 171 /* Build a  backend label declaration.  Set TREE_USED for named labels.
 172    The context of the label is always the current_function_decl.  All
 173    labels are marked artificial.  */
 174
 175 tree
 176 gfc_build_label_decl (tree label_id)
 177 {
 178   /* 2^32 temporaries should be enough.  */
 179   static unsigned int tmp_num = 1;
 180   tree label_decl;
 181   char *label_name;
 182
 183   if (label_id == NULL_TREE)
 184     {
 185       /* Build an internal label name.  */
 186       ASM_FORMAT_PRIVATE_NAME (label_name, "L", tmp_num++);
 187       label_id = get_identifier (label_name);
 188     }
 189   else
 190     label_name = NULL;
 191
 192   /* Build the LABEL_DECL node. Labels have no type.  */
 193   label_decl = build_decl (LABEL_DECL, label_id, void_type_node);
 194   DECL_CONTEXT (label_decl) = current_function_decl;
 195   DECL_MODE (label_decl) = VOIDmode;
 196
 197   /* We always define the label as used, even if the original source
 198      file never references the label.  We don't want all kinds of
 199      spurious warnings for old-style Fortran code with too many
 200      labels.  */
 201   TREE_USED (label_decl) = 1;
 202
 203   DECL_ARTIFICIAL (label_decl) = 1;
 204   return label_decl;
 205 }
 206
 207
 208 /* Returns the return label for the current function.  */
 209
 210 tree
 211 gfc_get_return_label (void)
 212 {
 213   char name[GFC_MAX_SYMBOL_LEN + 10];
 214
 215   if (current_function_return_label)
 216     return current_function_return_label;
 217
 218   sprintf (name, "__return_%s",
 219            IDENTIFIER_POINTER (DECL_NAME (current_function_decl)));
 220
 221   current_function_return_label =
 222     gfc_build_label_decl (get_identifier (name));
 223
 224   DECL_ARTIFICIAL (current_function_return_label) = 1;
 225
 226   return current_function_return_label;
 227 }
 228
 229
 230 /* Set the backend source location of a decl.  */
 231
 232 void
 233 gfc_set_decl_location (tree decl, locus * loc)
 234 {
 235 #ifdef USE_MAPPED_LOCATION
 236   DECL_SOURCE_LOCATION (decl) = loc->lb->location;
 237 #else
 238   DECL_SOURCE_LINE (decl) = loc->lb->linenum;
 239   DECL_SOURCE_FILE (decl) = loc->lb->file->filename;
 240 #endif
 241 }
 242
 243
 244 /* Return the backend label declaration for a given label structure,
 245    or create it if it doesn't exist yet.  */
 246
 247 tree
 248 gfc_get_label_decl (gfc_st_label * lp)
 249 {
 250   if (lp->backend_decl)
 251     return lp->backend_decl;
 252   else
 253     {
 254       char label_name[GFC_MAX_SYMBOL_LEN + 1];
 255       tree label_decl;
 256
 257       /* Validate the label declaration from the front end.  */
 258       gcc_assert (lp != NULL && lp->value <= MAX_LABEL_VALUE);
 259
 260       /* Build a mangled name for the label.  */
 261       sprintf (label_name, "__label_%.6d", lp->value);
 262
 263       /* Build the LABEL_DECL node.  */
 264       label_decl = gfc_build_label_decl (get_identifier (label_name));
 265
 266       /* Tell the debugger where the label came from.  */
 267       if (lp->value <= MAX_LABEL_VALUE) /* An internal label.  */
 268         gfc_set_decl_location (label_decl, &lp->where);
 269       else
 270         DECL_ARTIFICIAL (label_decl) = 1;
 271
 272       /* Store the label in the label list and return the LABEL_DECL.  */
 273       lp->backend_decl = label_decl;
 274       return label_decl;
 275     }
 276 }
 277
 278
 279 /* Convert a gfc_symbol to an identifier of the same name.  */
 280
 281 static tree
 282 gfc_sym_identifier (gfc_symbol * sym)
 283 {
 284   return (get_identifier (sym->name));
 285 }
 286
 287
 288 /* Construct mangled name from symbol name.  */
 289
 290 static tree
 291 gfc_sym_mangled_identifier (gfc_symbol * sym)
 292 {
 293   char name[GFC_MAX_MANGLED_SYMBOL_LEN + 1];
 294
 295   /* Prevent the mangling of identifiers that have an assigned
 296      binding label (mainly those that are bind(c)).  */
 297   if (sym->attr.is_bind_c == 1
 298       && sym->binding_label[0] != '\0')
 299     return get_identifier(sym->binding_label);
 300
 301   if (sym->module == NULL)
 302     return gfc_sym_identifier (sym);
 303   else
 304     {
 305       snprintf (name, sizeof name, "__%s_MOD_%s", sym->module, sym->name);
 306       return get_identifier (name);
 307     }
 308 }
 309
 310
 311 /* Construct mangled function name from symbol name.  */
 312
 313 static tree
 314 gfc_sym_mangled_function_id (gfc_symbol * sym)
 315 {
 316   int has_underscore;
 317   char name[GFC_MAX_MANGLED_SYMBOL_LEN + 1];
 318
 319   /* It may be possible to simply use the binding label if it's
 320      provided, and remove the other checks.  Then we could use it
 321      for other things if we wished.  */
 322   if ((sym->attr.is_bind_c == 1 || sym->attr.is_iso_c == 1) &&
 323       sym->binding_label[0] != '\0')
 324     /* use the binding label rather than the mangled name */
 325     return get_identifier (sym->binding_label);
 326
 327   if (sym->module == NULL || sym->attr.proc == PROC_EXTERNAL
 328       || (sym->module != NULL && (sym->attr.external
 329             || sym->attr.if_source == IFSRC_IFBODY)))
 330     {
 331       if (strcmp (sym->name, "MAIN__") == 0
 332           || sym->attr.proc == PROC_INTRINSIC)
 333         return get_identifier (sym->name);
 334
 335       if (gfc_option.flag_underscoring)
 336         {
 337           has_underscore = strchr (sym->name, '_') != 0;
 338           if (gfc_option.flag_second_underscore && has_underscore)
 339             snprintf (name, sizeof name, "%s__", sym->name);
 340           else
 341             snprintf (name, sizeof name, "%s_", sym->name);
 342           return get_identifier (name);
 343         }
 344       else
 345         return get_identifier (sym->name);
 346     }
 347   else
 348     {
 349       snprintf (name, sizeof name, "__%s_MOD_%s", sym->module, sym->name);
 350       return get_identifier (name);
 351     }
 352 }
 353
 354
 355 /* Returns true if a variable of specified size should go on the stack.  */
 356
 357 int
 358 gfc_can_put_var_on_stack (tree size)
 359 {
 360   unsigned HOST_WIDE_INT low;
 361
 362   if (!INTEGER_CST_P (size))
 363     return 0;
 364
 365   if (gfc_option.flag_max_stack_var_size < 0)
 366     return 1;
 367
 368   if (TREE_INT_CST_HIGH (size) != 0)
 369     return 0;
 370
 371   low = TREE_INT_CST_LOW (size);
 372   if (low > (unsigned HOST_WIDE_INT) gfc_option.flag_max_stack_var_size)
 373     return 0;
 374
 375 /* TODO: Set a per-function stack size limit.  */
 376
 377   return 1;
 378 }
 379
 380
 381 /* gfc_finish_cray_pointee sets DECL_VALUE_EXPR for a Cray pointee to
 382    an expression involving its corresponding pointer.  There are
 383    2 cases; one for variable size arrays, and one for everything else,
 384    because variable-sized arrays require one fewer level of
 385    indirection.  */
 386
 387 static void
 388 gfc_finish_cray_pointee (tree decl, gfc_symbol *sym)
 389 {
 390   tree ptr_decl = gfc_get_symbol_decl (sym->cp_pointer);
 391   tree value;
 392
 393   /* Parameters need to be dereferenced.  */
 394   if (sym->cp_pointer->attr.dummy)
 395     ptr_decl = build_fold_indirect_ref (ptr_decl);
 396
 397   /* Check to see if we're dealing with a variable-sized array.  */
 398   if (sym->attr.dimension
 399       && TREE_CODE (TREE_TYPE (decl)) == POINTER_TYPE)
 400     {
 401       /* These decls will be dereferenced later, so we don't dereference
 402          them here.  */
 403       value = convert (TREE_TYPE (decl), ptr_decl);
 404     }
 405   else
 406     {
 407       ptr_decl = convert (build_pointer_type (TREE_TYPE (decl)),
 408                           ptr_decl);
 409       value = build_fold_indirect_ref (ptr_decl);
 410     }
 411
 412   SET_DECL_VALUE_EXPR (decl, value);
 413   DECL_HAS_VALUE_EXPR_P (decl) = 1;
 414   GFC_DECL_CRAY_POINTEE (decl) = 1;
 415   /* This is a fake variable just for debugging purposes.  */
 416   TREE_ASM_WRITTEN (decl) = 1;
 417 }
 418
 419
 420 /* Finish processing of a declaration without an initial value.  */
 421
 422 static void
 423 gfc_finish_decl (tree decl)
 424 {
 425   gcc_assert (TREE_CODE (decl) == PARM_DECL
 426               || DECL_INITIAL (decl) == NULL_TREE);
 427
 428   if (TREE_CODE (decl) != VAR_DECL)
 429     return;
 430
 431   if (DECL_SIZE (decl) == NULL_TREE
 432       && TYPE_SIZE (TREE_TYPE (decl)) != NULL_TREE)
 433     layout_decl (decl, 0);
 434
 435   /* A few consistency checks.  */
 436   /* A static variable with an incomplete type is an error if it is
 437      initialized. Also if it is not file scope. Otherwise, let it
 438      through, but if it is not `extern' then it may cause an error
 439      message later.  */
 440   /* An automatic variable with an incomplete type is an error.  */
 441
 442   /* We should know the storage size.  */
 443   gcc_assert (DECL_SIZE (decl) != NULL_TREE
 444               || (TREE_STATIC (decl)
 445                   ? (!DECL_INITIAL (decl) || !DECL_CONTEXT (decl))
 446                   : DECL_EXTERNAL (decl)));
 447
 448   /* The storage size should be constant.  */
 449   gcc_assert ((!DECL_EXTERNAL (decl) && !TREE_STATIC (decl))
 450               || !DECL_SIZE (decl)
 451               || TREE_CODE (DECL_SIZE (decl)) == INTEGER_CST);
 452 }
 453
 454
 455 /* Apply symbol attributes to a variable, and add it to the function scope.  */
 456
 457 static void
 458 gfc_finish_var_decl (tree decl, gfc_symbol * sym)
 459 {
 460   tree new;
 461   /* TREE_ADDRESSABLE means the address of this variable is actually needed.
 462      This is the equivalent of the TARGET variables.
 463      We also need to set this if the variable is passed by reference in a
 464      CALL statement.  */
 465
 466   /* Set DECL_VALUE_EXPR for Cray Pointees.  */
 467   if (sym->attr.cray_pointee)
 468     gfc_finish_cray_pointee (decl, sym);
 469
 470   if (sym->attr.target)
 471     TREE_ADDRESSABLE (decl) = 1;
 472   /* If it wasn't used we wouldn't be getting it.  */
 473   TREE_USED (decl) = 1;
 474
 475   /* Chain this decl to the pending declarations.  Don't do pushdecl()
 476      because this would add them to the current scope rather than the
 477      function scope.  */
 478   if (current_function_decl != NULL_TREE)
 479     {
 480       if (sym->ns->proc_name->backend_decl == current_function_decl
 481           || sym->result == sym)
 482         gfc_add_decl_to_function (decl);
 483       else
 484         gfc_add_decl_to_parent_function (decl);
 485     }
 486
 487   if (sym->attr.cray_pointee)
 488     return;
 489
 490   if(sym->attr.is_bind_c == 1)
 491     {
 492       /* We need to put variables that are bind(c) into the common
 493          segment of the object file, because this is what C would do.
 494          gfortran would typically put them in either the BSS or
 495          initialized data segments, and only mark them as common if
 496          they were part of common blocks.  However, if they are not put
 497          into common space, then C cannot initialize global fortran
 498          variables that it interoperates with and the draft says that
 499          either Fortran or C should be able to initialize it (but not
 500          both, of course.) (J3/04-007, section 15.3).  */
 501       TREE_PUBLIC(decl) = 1;
 502       DECL_COMMON(decl) = 1;
 503     }
 504
 505   /* If a variable is USE associated, it's always external.  */
 506   if (sym->attr.use_assoc)
 507     {
 508       DECL_EXTERNAL (decl) = 1;
 509       TREE_PUBLIC (decl) = 1;
 510     }
 511   else if (sym->module && !sym->attr.result && !sym->attr.dummy)
 512     {
 513       /* TODO: Don't set sym->module for result or dummy variables.  */
 514       gcc_assert (current_function_decl == NULL_TREE || sym->result == sym);
 515       /* This is the declaration of a module variable.  */
 516       TREE_PUBLIC (decl) = 1;
 517       TREE_STATIC (decl) = 1;
 518     }
 519
 520   if ((sym->attr.save || sym->attr.data || sym->value)
 521       && !sym->attr.use_assoc)
 522     TREE_STATIC (decl) = 1;
 523
 524   if (sym->attr.volatile_)
 525     {
 526       TREE_THIS_VOLATILE (decl) = 1;
 527       new = build_qualified_type (TREE_TYPE (decl), TYPE_QUAL_VOLATILE);
 528       TREE_TYPE (decl) = new;
 529     }
 530
 531   /* Keep variables larger than max-stack-var-size off stack.  */
 532   if (!sym->ns->proc_name->attr.recursive
 533       && INTEGER_CST_P (DECL_SIZE_UNIT (decl))
 534       && !gfc_can_put_var_on_stack (DECL_SIZE_UNIT (decl))
 535          /* Put variable length auto array pointers always into stack.  */
 536       && (TREE_CODE (TREE_TYPE (decl)) != POINTER_TYPE
 537           || sym->attr.dimension == 0
 538           || sym->as->type != AS_EXPLICIT
 539           || sym->attr.pointer
 540           || sym->attr.allocatable)
 541       && !DECL_ARTIFICIAL (decl))
 542     TREE_STATIC (decl) = 1;
 543
 544   /* Handle threadprivate variables.  */
 545   if (sym->attr.threadprivate
 546       && (TREE_STATIC (decl) || DECL_EXTERNAL (decl)))
 547     DECL_TLS_MODEL (decl) = decl_default_tls_model (decl);
 548 }
 549
 550
 551 /* Allocate the lang-specific part of a decl.  */
 552
 553 void
 554 gfc_allocate_lang_decl (tree decl)
 555 {
 556   DECL_LANG_SPECIFIC (decl) = (struct lang_decl *)
 557     ggc_alloc_cleared (sizeof (struct lang_decl));
 558 }
 559
 560 /* Remember a symbol to generate initialization/cleanup code at function
 561    entry/exit.  */
 562
 563 static void
 564 gfc_defer_symbol_init (gfc_symbol * sym)
 565 {
 566   gfc_symbol *p;
 567   gfc_symbol *last;
 568   gfc_symbol *head;
 569
 570   /* Don't add a symbol twice.  */
 571   if (sym->tlink)
 572     return;
 573
 574   last = head = sym->ns->proc_name;
 575   p = last->tlink;
 576
 577   /* Make sure that setup code for dummy variables which are used in the
 578      setup of other variables is generated first.  */
 579   if (sym->attr.dummy)
 580     {
 581       /* Find the first dummy arg seen after us, or the first non-dummy arg.
 582          This is a circular list, so don't go past the head.  */
 583       while (p != head
 584              && (!p->attr.dummy || p->dummy_order > sym->dummy_order))
 585         {
 586           last = p;
 587           p = p->tlink;
 588         }
 589     }
 590   /* Insert in between last and p.  */
 591   last->tlink = sym;
 592   sym->tlink = p;
 593 }
 594
 595
 596 /* Create an array index type variable with function scope.  */
 597
 598 static tree
 599 create_index_var (const char * pfx, int nest)
 600 {
 601   tree decl;
 602
 603   decl = gfc_create_var_np (gfc_array_index_type, pfx);
 604   if (nest)
 605     gfc_add_decl_to_parent_function (decl);
 606   else
 607     gfc_add_decl_to_function (decl);
 608   return decl;
 609 }
 610
 611
 612 /* Create variables to hold all the non-constant bits of info for a
 613    descriptorless array.  Remember these in the lang-specific part of the
 614    type.  */
 615
 616 static void
 617 gfc_build_qualified_array (tree decl, gfc_symbol * sym)
 618 {
 619   tree type;
 620   int dim;
 621   int nest;
 622
 623   type = TREE_TYPE (decl);
 624
 625   /* We just use the descriptor, if there is one.  */
 626   if (GFC_DESCRIPTOR_TYPE_P (type))
 627     return;
 628
 629   gcc_assert (GFC_ARRAY_TYPE_P (type));
 630   nest = (sym->ns->proc_name->backend_decl != current_function_decl)
 631          && !sym->attr.contained;
 632
 633   for (dim = 0; dim < GFC_TYPE_ARRAY_RANK (type); dim++)
 634     {
 635       if (GFC_TYPE_ARRAY_LBOUND (type, dim) == NULL_TREE)
 636         {
 637           GFC_TYPE_ARRAY_LBOUND (type, dim) = create_index_var ("lbound", nest);
 638           TREE_NO_WARNING (GFC_TYPE_ARRAY_LBOUND (type, dim)) = 1;
 639         }
 640       /* Don't try to use the unknown bound for assumed shape arrays.  */
 641       if (GFC_TYPE_ARRAY_UBOUND (type, dim) == NULL_TREE
 642           && (sym->as->type != AS_ASSUMED_SIZE
 643               || dim < GFC_TYPE_ARRAY_RANK (type) - 1))
 644         {
 645           GFC_TYPE_ARRAY_UBOUND (type, dim) = create_index_var ("ubound", nest);
 646           TREE_NO_WARNING (GFC_TYPE_ARRAY_UBOUND (type, dim)) = 1;
 647         }
 648
 649       if (GFC_TYPE_ARRAY_STRIDE (type, dim) == NULL_TREE)
 650         {
 651           GFC_TYPE_ARRAY_STRIDE (type, dim) = create_index_var ("stride", nest);
 652           TREE_NO_WARNING (GFC_TYPE_ARRAY_STRIDE (type, dim)) = 1;
 653         }
 654     }
 655   if (GFC_TYPE_ARRAY_OFFSET (type) == NULL_TREE)
 656     {
 657       GFC_TYPE_ARRAY_OFFSET (type) = gfc_create_var_np (gfc_array_index_type,
 658                                                         "offset");
 659       TREE_NO_WARNING (GFC_TYPE_ARRAY_OFFSET (type)) = 1;
 660
 661       if (nest)
 662         gfc_add_decl_to_parent_function (GFC_TYPE_ARRAY_OFFSET (type));
 663       else
 664         gfc_add_decl_to_function (GFC_TYPE_ARRAY_OFFSET (type));
 665     }
 666
 667   if (GFC_TYPE_ARRAY_SIZE (type) == NULL_TREE
 668       && sym->as->type != AS_ASSUMED_SIZE)
 669     {
 670       GFC_TYPE_ARRAY_SIZE (type) = create_index_var ("size", nest);
 671       TREE_NO_WARNING (GFC_TYPE_ARRAY_SIZE (type)) = 1;
 672     }
 673
 674   if (POINTER_TYPE_P (type))
 675     {
 676       gcc_assert (GFC_ARRAY_TYPE_P (TREE_TYPE (type)));
 677       gcc_assert (TYPE_LANG_SPECIFIC (type)
 678                   == TYPE_LANG_SPECIFIC (TREE_TYPE (type)));
 679       type = TREE_TYPE (type);
 680     }
 681
 682   if (! COMPLETE_TYPE_P (type) && GFC_TYPE_ARRAY_SIZE (type))
 683     {
 684       tree size, range;
 685
 686       size = build2 (MINUS_EXPR, gfc_array_index_type,
 687                      GFC_TYPE_ARRAY_SIZE (type), gfc_index_one_node);
 688       range = build_range_type (gfc_array_index_type, gfc_index_zero_node,
 689                                 size);
 690       TYPE_DOMAIN (type) = range;
 691       layout_type (type);
 692     }
 693 }
 694
 695
 696 /* For some dummy arguments we don't use the actual argument directly.
 697    Instead we create a local decl and use that.  This allows us to perform
 698    initialization, and construct full type information.  */
 699
 700 static tree
 701 gfc_build_dummy_array_decl (gfc_symbol * sym, tree dummy)
 702 {
 703   tree decl;
 704   tree type;
 705   gfc_array_spec *as;
 706   char *name;
 707   gfc_packed packed;
 708   int n;
 709   bool known_size;
 710
 711   if (sym->attr.pointer || sym->attr.allocatable)
 712     return dummy;
 713
 714   /* Add to list of variables if not a fake result variable.  */
 715   if (sym->attr.result || sym->attr.dummy)
 716     gfc_defer_symbol_init (sym);
 717
 718   type = TREE_TYPE (dummy);
 719   gcc_assert (TREE_CODE (dummy) == PARM_DECL
 720           && POINTER_TYPE_P (type));
 721
 722   /* Do we know the element size?  */
 723   known_size = sym->ts.type != BT_CHARACTER
 724           || INTEGER_CST_P (sym->ts.cl->backend_decl);
 725
 726   if (known_size && !GFC_DESCRIPTOR_TYPE_P (TREE_TYPE (type)))
 727     {
 728       /* For descriptorless arrays with known element size the actual
 729          argument is sufficient.  */
 730       gcc_assert (GFC_ARRAY_TYPE_P (type));
 731       gfc_build_qualified_array (dummy, sym);
 732       return dummy;
 733     }
 734
 735   type = TREE_TYPE (type);
 736   if (GFC_DESCRIPTOR_TYPE_P (type))
 737     {
 738       /* Create a descriptorless array pointer.  */
 739       as = sym->as;
 740       packed = PACKED_NO;
 741       if (!gfc_option.flag_repack_arrays)
 742         {
 743           if (as->type == AS_ASSUMED_SIZE)
 744             packed = PACKED_FULL;
 745         }
 746       else
 747         {
 748           if (as->type == AS_EXPLICIT)
 749             {
 750               packed = PACKED_FULL;
 751               for (n = 0; n < as->rank; n++)
 752                 {
 753                   if (!(as->upper[n]
 754                         && as->lower[n]
 755                         && as->upper[n]->expr_type == EXPR_CONSTANT
 756                         && as->lower[n]->expr_type == EXPR_CONSTANT))
 757                     packed = PACKED_PARTIAL;
 758                 }
 759             }
 760           else
 761             packed = PACKED_PARTIAL;
 762         }
 763
 764       type = gfc_typenode_for_spec (&sym->ts);
 765       type = gfc_get_nodesc_array_type (type, sym->as, packed);
 766     }
 767   else
 768     {
 769       /* We now have an expression for the element size, so create a fully
 770          qualified type.  Reset sym->backend decl or this will just return the
 771          old type.  */
 772       DECL_ARTIFICIAL (sym->backend_decl) = 1;
 773       sym->backend_decl = NULL_TREE;
 774       type = gfc_sym_type (sym);
 775       packed = PACKED_FULL;
 776     }
 777
 778   ASM_FORMAT_PRIVATE_NAME (name, IDENTIFIER_POINTER (DECL_NAME (dummy)), 0);
 779   decl = build_decl (VAR_DECL, get_identifier (name), type);
 780
 781   DECL_ARTIFICIAL (decl) = 1;
 782   TREE_PUBLIC (decl) = 0;
 783   TREE_STATIC (decl) = 0;
 784   DECL_EXTERNAL (decl) = 0;
 785
 786   /* We should never get deferred shape arrays here.  We used to because of
 787      frontend bugs.  */
 788   gcc_assert (sym->as->type != AS_DEFERRED);
 789
 790   if (packed == PACKED_PARTIAL)
 791     GFC_DECL_PARTIAL_PACKED_ARRAY (decl) = 1;
 792   else if (packed == PACKED_FULL)
 793     GFC_DECL_PACKED_ARRAY (decl) = 1;
 794
 795   gfc_build_qualified_array (decl, sym);
 796
 797   if (DECL_LANG_SPECIFIC (dummy))
 798     DECL_LANG_SPECIFIC (decl) = DECL_LANG_SPECIFIC (dummy);
 799   else
 800     gfc_allocate_lang_decl (decl);
 801
 802   GFC_DECL_SAVED_DESCRIPTOR (decl) = dummy;
 803
 804   if (sym->ns->proc_name->backend_decl == current_function_decl
 805       || sym->attr.contained)
 806     gfc_add_decl_to_function (decl);
 807   else
 808     gfc_add_decl_to_parent_function (decl);
 809
 810   return decl;
 811 }
 812
 813
 814 /* Return a constant or a variable to use as a string length.  Does not
 815    add the decl to the current scope.  */
 816
 817 static tree
 818 gfc_create_string_length (gfc_symbol * sym)
 819 {
 820   tree length;
 821
 822   gcc_assert (sym->ts.cl);
 823   gfc_conv_const_charlen (sym->ts.cl);
 824
 825   if (sym->ts.cl->backend_decl == NULL_TREE)
 826     {
 827       char name[GFC_MAX_MANGLED_SYMBOL_LEN + 2];
 828
 829       /* Also prefix the mangled name.  */
 830       strcpy (&name[1], sym->name);
 831       name[0] = '.';
 832       length = build_decl (VAR_DECL, get_identifier (name),
 833                            gfc_charlen_type_node);
 834       DECL_ARTIFICIAL (length) = 1;
 835       TREE_USED (length) = 1;
 836       if (sym->ns->proc_name->tlink != NULL)
 837         gfc_defer_symbol_init (sym);
 838       sym->ts.cl->backend_decl = length;
 839     }
 840
 841   return sym->ts.cl->backend_decl;
 842 }
 843
 844 /* If a variable is assigned a label, we add another two auxiliary
 845    variables.  */
 846
 847 static void
 848 gfc_add_assign_aux_vars (gfc_symbol * sym)
 849 {
 850   tree addr;
 851   tree length;
 852   tree decl;
 853
 854   gcc_assert (sym->backend_decl);
 855
 856   decl = sym->backend_decl;
 857   gfc_allocate_lang_decl (decl);
 858   GFC_DECL_ASSIGN (decl) = 1;
 859   length = build_decl (VAR_DECL, create_tmp_var_name (sym->name),
 860                        gfc_charlen_type_node);
 861   addr = build_decl (VAR_DECL, create_tmp_var_name (sym->name),
 862                      pvoid_type_node);
 863   gfc_finish_var_decl (length, sym);
 864   gfc_finish_var_decl (addr, sym);
 865   /*  STRING_LENGTH is also used as flag. Less than -1 means that
 866       ASSIGN_ADDR can not be used. Equal -1 means that ASSIGN_ADDR is the
 867       target label's address. Otherwise, value is the length of a format string
 868       and ASSIGN_ADDR is its address.  */
 869   if (TREE_STATIC (length))
 870     DECL_INITIAL (length) = build_int_cst (NULL_TREE, -2);
 871   else
 872     gfc_defer_symbol_init (sym);
 873
 874   GFC_DECL_STRING_LEN (decl) = length;
 875   GFC_DECL_ASSIGN_ADDR (decl) = addr;
 876 }
 877
 878 /* Return the decl for a gfc_symbol, create it if it doesn't already
 879    exist.  */
 880
 881 tree
 882 gfc_get_symbol_decl (gfc_symbol * sym)
 883 {
 884   tree decl;
 885   tree length = NULL_TREE;
 886   int byref;
 887
 888   gcc_assert (sym->attr.referenced
 889                 || sym->attr.use_assoc
 890                 || sym->ns->proc_name->attr.if_source == IFSRC_IFBODY);
 891
 892   if (sym->ns && sym->ns->proc_name->attr.function)
 893     byref = gfc_return_by_reference (sym->ns->proc_name);
 894   else
 895     byref = 0;
 896
 897   if ((sym->attr.dummy && ! sym->attr.function) || (sym->attr.result && byref))
 898     {
 899       /* Return via extra parameter.  */
 900       if (sym->attr.result && byref
 901           && !sym->backend_decl)
 902         {
 903           sym->backend_decl =
 904             DECL_ARGUMENTS (sym->ns->proc_name->backend_decl);
 905           /* For entry master function skip over the __entry
 906              argument.  */
 907           if (sym->ns->proc_name->attr.entry_master)
 908             sym->backend_decl = TREE_CHAIN (sym->backend_decl);
 909         }
 910
 911       /* Dummy variables should already have been created.  */
 912       gcc_assert (sym->backend_decl);
 913
 914       /* Create a character length variable.  */
 915       if (sym->ts.type == BT_CHARACTER)
 916         {
 917           if (sym->ts.cl->backend_decl == NULL_TREE)
 918             length = gfc_create_string_length (sym);
 919           else
 920             length = sym->ts.cl->backend_decl;
 921           if (TREE_CODE (length) == VAR_DECL
 922               && DECL_CONTEXT (length) == NULL_TREE)
 923             {
 924               /* Add the string length to the same context as the symbol.  */
 925               if (DECL_CONTEXT (sym->backend_decl) == current_function_decl)
 926                 gfc_add_decl_to_function (length);
 927               else
 928                 gfc_add_decl_to_parent_function (length);
 929
 930               gcc_assert (DECL_CONTEXT (sym->backend_decl) ==
 931                             DECL_CONTEXT (length));
 932
 933               gfc_defer_symbol_init (sym);
 934             }
 935         }
 936
 937       /* Use a copy of the descriptor for dummy arrays.  */
 938       if (sym->attr.dimension && !TREE_USED (sym->backend_decl))
 939         {
 940           decl = gfc_build_dummy_array_decl (sym, sym->backend_decl);
 941           /* Prevent the dummy from being detected as unused if it is copied.  */
 942           if (sym->backend_decl != NULL && decl != sym->backend_decl)
 943             DECL_ARTIFICIAL (sym->backend_decl) = 1;
 944           sym->backend_decl = decl;
 945         }
 946
 947       TREE_USED (sym->backend_decl) = 1;
 948       if (sym->attr.assign && GFC_DECL_ASSIGN (sym->backend_decl) == 0)
 949         {
 950           gfc_add_assign_aux_vars (sym);
 951         }
 952       return sym->backend_decl;
 953     }
 954
 955   if (sym->backend_decl)
 956     return sym->backend_decl;
 957
 958   /* Catch function declarations.  Only used for actual parameters.  */
 959   if (sym->attr.flavor == FL_PROCEDURE)
 960     {
 961       decl = gfc_get_extern_function_decl (sym);
 962       return decl;
 963     }
 964
 965   if (sym->attr.intrinsic)
 966     internal_error ("intrinsic variable which isn't a procedure");
 967
 968   /* Create string length decl first so that they can be used in the
 969      type declaration.  */
 970   if (sym->ts.type == BT_CHARACTER)
 971     length = gfc_create_string_length (sym);
 972
 973   /* Create the decl for the variable.  */
 974   decl = build_decl (VAR_DECL, gfc_sym_identifier (sym), gfc_sym_type (sym));
 975
 976   gfc_set_decl_location (decl, &sym->declared_at);
 977
 978   /* Symbols from modules should have their assembler names mangled.
 979      This is done here rather than in gfc_finish_var_decl because it
 980      is different for string length variables.  */
 981   if (sym->module)
 982     SET_DECL_ASSEMBLER_NAME (decl, gfc_sym_mangled_identifier (sym));
 983
 984   if (sym->attr.dimension)
 985     {
 986       /* Create variables to hold the non-constant bits of array info.  */
 987       gfc_build_qualified_array (decl, sym);
 988
 989       /* Remember this variable for allocation/cleanup.  */
 990       gfc_defer_symbol_init (sym);
 991
 992       if ((sym->attr.allocatable || !sym->attr.dummy) && !sym->attr.pointer)
 993         GFC_DECL_PACKED_ARRAY (decl) = 1;
 994     }
 995
 996   if (sym->ts.type == BT_DERIVED && sym->ts.derived->attr.alloc_comp)
 997     gfc_defer_symbol_init (sym);
 998
 999   gfc_finish_var_decl (decl, sym);
1000
1001   if (sym->ts.type == BT_CHARACTER)
1002     {
1003       /* Character variables need special handling.  */
1004       gfc_allocate_lang_decl (decl);
1005
1006       if (TREE_CODE (length) != INTEGER_CST)
1007         {
1008           char name[GFC_MAX_MANGLED_SYMBOL_LEN + 2];
1009
1010           if (sym->module)
1011             {
1012               /* Also prefix the mangled name for symbols from modules.  */
1013               strcpy (&name[1], sym->name);
1014               name[0] = '.';
1015               strcpy (&name[1],
1016                       IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (length)));
1017               SET_DECL_ASSEMBLER_NAME (decl, get_identifier (name));
1018             }
1019           gfc_finish_var_decl (length, sym);
1020           gcc_assert (!sym->value);
1021         }
1022     }
1023   sym->backend_decl = decl;
1024
1025   if (sym->attr.assign)
1026     gfc_add_assign_aux_vars (sym);
1027
1028   if (TREE_STATIC (decl) && !sym->attr.use_assoc)
1029     {
1030       /* Add static initializer.  */
1031       DECL_INITIAL (decl) = gfc_conv_initializer (sym->value, &sym->ts,
1032           TREE_TYPE (decl), sym->attr.dimension,
1033           sym->attr.pointer || sym->attr.allocatable);
1034     }
1035
1036   return decl;
1037 }
1038
1039
1040 /* Substitute a temporary variable in place of the real one.  */
1041
1042 void
1043 gfc_shadow_sym (gfc_symbol * sym, tree decl, gfc_saved_var * save)
1044 {
1045   save->attr = sym->attr;
1046   save->decl = sym->backend_decl;
1047
1048   gfc_clear_attr (&sym->attr);
1049   sym->attr.referenced = 1;
1050   sym->attr.flavor = FL_VARIABLE;
1051
1052   sym->backend_decl = decl;
1053 }
1054
1055
1056 /* Restore the original variable.  */
1057
1058 void
1059 gfc_restore_sym (gfc_symbol * sym, gfc_saved_var * save)
1060 {
1061   sym->attr = save->attr;
1062   sym->backend_decl = save->decl;
1063 }
1064
1065
1066 /* Get a basic decl for an external function.  */
1067
1068 tree
1069 gfc_get_extern_function_decl (gfc_symbol * sym)
1070 {
1071   tree type;
1072   tree fndecl;
1073   gfc_expr e;
1074   gfc_intrinsic_sym *isym;
1075   gfc_expr argexpr;
1076   char s[GFC_MAX_SYMBOL_LEN + 23]; /* "_gfortran_f2c_specific" and '\0'.  */
1077   tree name;
1078   tree mangled_name;
1079
1080   if (sym->backend_decl)
1081     return sym->backend_decl;
1082
1083   /* We should never be creating external decls for alternate entry points.
1084      The procedure may be an alternate entry point, but we don't want/need
1085      to know that.  */
1086   gcc_assert (!(sym->attr.entry || sym->attr.entry_master));
1087
1088   if (sym->attr.intrinsic)
1089     {
1090       /* Call the resolution function to get the actual name.  This is
1091          a nasty hack which relies on the resolution functions only looking
1092          at the first argument.  We pass NULL for the second argument
1093          otherwise things like AINT get confused.  */
1094       isym = gfc_find_function (sym->name);
1095       gcc_assert (isym->resolve.f0 != NULL);
1096
1097       memset (&e, 0, sizeof (e));
1098       e.expr_type = EXPR_FUNCTION;
1099
1100       memset (&argexpr, 0, sizeof (argexpr));
1101       gcc_assert (isym->formal);
1102       argexpr.ts = isym->formal->ts;
1103
1104       if (isym->formal->next == NULL)
1105         isym->resolve.f1 (&e, &argexpr);
1106       else
1107         {
1108           if (isym->formal->next->next == NULL)
1109             isym->resolve.f2 (&e, &argexpr, NULL);
1110           else
1111             {
1112               /* All specific intrinsics take less than 4 arguments.  */
1113               gcc_assert (isym->formal->next->next->next == NULL);
1114               isym->resolve.f3 (&e, &argexpr, NULL, NULL);
1115             }
1116         }
1117
1118       if (gfc_option.flag_f2c
1119           && ((e.ts.type == BT_REAL && e.ts.kind == gfc_default_real_kind)
1120               || e.ts.type == BT_COMPLEX))
1121         {
1122           /* Specific which needs a different implementation if f2c
1123              calling conventions are used.  */
1124           sprintf (s, "_gfortran_f2c_specific%s", e.value.function.name);
1125         }
1126       else
1127         sprintf (s, "_gfortran_specific%s", e.value.function.name);
1128
1129       name = get_identifier (s);
1130       mangled_name = name;
1131     }
1132   else
1133     {
1134       name = gfc_sym_identifier (sym);
1135       mangled_name = gfc_sym_mangled_function_id (sym);
1136     }
1137
1138   type = gfc_get_function_type (sym);
1139   fndecl = build_decl (FUNCTION_DECL, name, type);
1140
1141   SET_DECL_ASSEMBLER_NAME (fndecl, mangled_name);
1142   /* If the return type is a pointer, avoid alias issues by setting
1143      DECL_IS_MALLOC to nonzero. This means that the function should be
1144      treated as if it were a malloc, meaning it returns a pointer that
1145      is not an alias.  */
1146   if (POINTER_TYPE_P (type))
1147     DECL_IS_MALLOC (fndecl) = 1;
1148
1149   /* Set the context of this decl.  */
1150   if (0 && sym->ns && sym->ns->proc_name)
1151     {
1152       /* TODO: Add external decls to the appropriate scope.  */
1153       DECL_CONTEXT (fndecl) = sym->ns->proc_name->backend_decl;
1154     }
1155   else
1156     {
1157       /* Global declaration, e.g. intrinsic subroutine.  */
1158       DECL_CONTEXT (fndecl) = NULL_TREE;
1159     }
1160
1161   DECL_EXTERNAL (fndecl) = 1;
1162
1163   /* This specifies if a function is globally addressable, i.e. it is
1164      the opposite of declaring static in C.  */
1165   TREE_PUBLIC (fndecl) = 1;
1166
1167   /* Set attributes for PURE functions. A call to PURE function in the
1168      Fortran 95 sense is both pure and without side effects in the C
1169      sense.  */
1170   if (sym->attr.pure || sym->attr.elemental)
1171     {
1172       if (sym->attr.function && !gfc_return_by_reference (sym))
1173         DECL_IS_PURE (fndecl) = 1;
1174       /* TODO: check if pure SUBROUTINEs don't have INTENT(OUT)
1175          parameters and don't use alternate returns (is this
1176          allowed?). In that case, calls to them are meaningless, and
1177          can be optimized away. See also in build_function_decl().  */
1178       TREE_SIDE_EFFECTS (fndecl) = 0;
1179     }
1180
1181   /* Mark non-returning functions.  */
1182   if (sym->attr.noreturn)
1183       TREE_THIS_VOLATILE(fndecl) = 1;
1184
1185   sym->backend_decl = fndecl;
1186
1187   if (DECL_CONTEXT (fndecl) == NULL_TREE)
1188     pushdecl_top_level (fndecl);
1189
1190   return fndecl;
1191 }
1192
1193
1194 /* Create a declaration for a procedure.  For external functions (in the C
1195    sense) use gfc_get_extern_function_decl.  HAS_ENTRIES is true if this is
1196    a master function with alternate entry points.  */
1197
1198 static void
1199 build_function_decl (gfc_symbol * sym)
1200 {
1201   tree fndecl, type;
1202   symbol_attribute attr;
1203   tree result_decl;
1204   gfc_formal_arglist *f;
1205
1206   gcc_assert (!sym->backend_decl);
1207   gcc_assert (!sym->attr.external);
1208
1209   /* Set the line and filename.  sym->declared_at seems to point to the
1210      last statement for subroutines, but it'll do for now.  */
1211   gfc_set_backend_locus (&sym->declared_at);
1212
1213   /* Allow only one nesting level.  Allow public declarations.  */
1214   gcc_assert (current_function_decl == NULL_TREE
1215           || DECL_CONTEXT (current_function_decl) == NULL_TREE);
1216
1217   type = gfc_get_function_type (sym);
1218   fndecl = build_decl (FUNCTION_DECL, gfc_sym_identifier (sym), type);
1219
1220   /* Perform name mangling if this is a top level or module procedure.  */
1221   if (current_function_decl == NULL_TREE)
1222     SET_DECL_ASSEMBLER_NAME (fndecl, gfc_sym_mangled_function_id (sym));
1223
1224   /* Figure out the return type of the declared function, and build a
1225      RESULT_DECL for it.  If this is a subroutine with alternate
1226      returns, build a RESULT_DECL for it.  */
1227   attr = sym->attr;
1228
1229   result_decl = NULL_TREE;
1230   /* TODO: Shouldn't this just be TREE_TYPE (TREE_TYPE (fndecl)).  */
1231   if (attr.function)
1232     {
1233       if (gfc_return_by_reference (sym))
1234         type = void_type_node;
1235       else
1236         {
1237           if (sym->result != sym)
1238             result_decl = gfc_sym_identifier (sym->result);
1239
1240           type = TREE_TYPE (TREE_TYPE (fndecl));
1241         }
1242     }
1243   else
1244     {
1245       /* Look for alternate return placeholders.  */
1246       int has_alternate_returns = 0;
1247       for (f = sym->formal; f; f = f->next)
1248         {
1249           if (f->sym == NULL)
1250             {
1251               has_alternate_returns = 1;
1252               break;
1253             }
1254         }
1255
1256       if (has_alternate_returns)
1257         type = integer_type_node;
1258       else
1259         type = void_type_node;
1260     }
1261
1262   result_decl = build_decl (RESULT_DECL, result_decl, type);
1263   DECL_ARTIFICIAL (result_decl) = 1;
1264   DECL_IGNORED_P (result_decl) = 1;
1265   DECL_CONTEXT (result_decl) = fndecl;
1266   DECL_RESULT (fndecl) = result_decl;
1267
1268   /* Don't call layout_decl for a RESULT_DECL.
1269      layout_decl (result_decl, 0);  */
1270
1271   /* If the return type is a pointer, avoid alias issues by setting
1272      DECL_IS_MALLOC to nonzero. This means that the function should be
1273      treated as if it were a malloc, meaning it returns a pointer that
1274      is not an alias.  */
1275   if (POINTER_TYPE_P (type))
1276     DECL_IS_MALLOC (fndecl) = 1;
1277
1278   /* Set up all attributes for the function.  */
1279   DECL_CONTEXT (fndecl) = current_function_decl;
1280   DECL_EXTERNAL (fndecl) = 0;
1281
1282   /* This specifies if a function is globally visible, i.e. it is
1283      the opposite of declaring static in C.  */
1284   if (DECL_CONTEXT (fndecl) == NULL_TREE
1285       && !sym->attr.entry_master)
1286     TREE_PUBLIC (fndecl) = 1;
1287
1288   /* TREE_STATIC means the function body is defined here.  */
1289   TREE_STATIC (fndecl) = 1;
1290
1291   /* Set attributes for PURE functions. A call to a PURE function in the
1292      Fortran 95 sense is both pure and without side effects in the C
1293      sense.  */
1294   if (attr.pure || attr.elemental)
1295     {
1296       /* TODO: check if a pure SUBROUTINE has no INTENT(OUT) arguments
1297          including an alternate return. In that case it can also be
1298          marked as PURE. See also in gfc_get_extern_function_decl().  */
1299       if (attr.function && !gfc_return_by_reference (sym))
1300         DECL_IS_PURE (fndecl) = 1;
1301       TREE_SIDE_EFFECTS (fndecl) = 0;
1302     }
1303
1304   /* Layout the function declaration and put it in the binding level
1305      of the current function.  */
1306   pushdecl (fndecl);
1307
1308   sym->backend_decl = fndecl;
1309 }
1310
1311
1312 /* Create the DECL_ARGUMENTS for a procedure.  */
1313
1314 static void
1315 create_function_arglist (gfc_symbol * sym)
1316 {
1317   tree fndecl;
1318   gfc_formal_arglist *f;
1319   tree typelist, hidden_typelist;
1320   tree arglist, hidden_arglist;
1321   tree type;
1322   tree parm;
1323
1324   fndecl = sym->backend_decl;
1325
1326   /* Build formal argument list. Make sure that their TREE_CONTEXT is
1327      the new FUNCTION_DECL node.  */
1328   arglist = NULL_TREE;
1329   hidden_arglist = NULL_TREE;
1330   typelist = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
1331
1332   if (sym->attr.entry_master)
1333     {
1334       type = TREE_VALUE (typelist);
1335       parm = build_decl (PARM_DECL, get_identifier ("__entry"), type);
1336
1337       DECL_CONTEXT (parm) = fndecl;
1338       DECL_ARG_TYPE (parm) = type;
1339       TREE_READONLY (parm) = 1;
1340       gfc_finish_decl (parm);
1341       DECL_ARTIFICIAL (parm) = 1;
1342
1343       arglist = chainon (arglist, parm);
1344       typelist = TREE_CHAIN (typelist);
1345     }
1346
1347   if (gfc_return_by_reference (sym))
1348     {
1349       tree type = TREE_VALUE (typelist), length = NULL;
1350
1351       if (sym->ts.type == BT_CHARACTER)
1352         {
1353           /* Length of character result.  */
1354           tree len_type = TREE_VALUE (TREE_CHAIN (typelist));
1355           gcc_assert (len_type == gfc_charlen_type_node);
1356
1357           length = build_decl (PARM_DECL,
1358                                get_identifier (".__result"),
1359                                len_type);
1360           if (!sym->ts.cl->length)
1361             {
1362               sym->ts.cl->backend_decl = length;
1363               TREE_USED (length) = 1;
1364             }
1365           gcc_assert (TREE_CODE (length) == PARM_DECL);
1366           DECL_CONTEXT (length) = fndecl;
1367           DECL_ARG_TYPE (length) = len_type;
1368           TREE_READONLY (length) = 1;
1369           DECL_ARTIFICIAL (length) = 1;
1370           gfc_finish_decl (length);
1371           if (sym->ts.cl->backend_decl == NULL
1372               || sym->ts.cl->backend_decl == length)
1373             {
1374               gfc_symbol *arg;
1375               tree backend_decl;
1376
1377               if (sym->ts.cl->backend_decl == NULL)
1378                 {
1379                   tree len = build_decl (VAR_DECL,
1380                                          get_identifier ("..__result"),
1381                                          gfc_charlen_type_node);
1382                   DECL_ARTIFICIAL (len) = 1;
1383                   TREE_USED (len) = 1;
1384                   sym->ts.cl->backend_decl = len;
1385                 }
1386
1387               /* Make sure PARM_DECL type doesn't point to incomplete type.  */
1388               arg = sym->result ? sym->result : sym;
1389               backend_decl = arg->backend_decl;
1390               /* Temporary clear it, so that gfc_sym_type creates complete
1391                  type.  */
1392               arg->backend_decl = NULL;
1393               type = gfc_sym_type (arg);
1394               arg->backend_decl = backend_decl;
1395               type = build_reference_type (type);
1396             }
1397         }
1398
1399       parm = build_decl (PARM_DECL, get_identifier ("__result"), type);
1400
1401       DECL_CONTEXT (parm) = fndecl;
1402       DECL_ARG_TYPE (parm) = TREE_VALUE (typelist);
1403       TREE_READONLY (parm) = 1;
1404       DECL_ARTIFICIAL (parm) = 1;
1405       gfc_finish_decl (parm);
1406
1407       arglist = chainon (arglist, parm);
1408       typelist = TREE_CHAIN (typelist);
1409
1410       if (sym->ts.type == BT_CHARACTER)
1411         {
1412           gfc_allocate_lang_decl (parm);
1413           arglist = chainon (arglist, length);
1414           typelist = TREE_CHAIN (typelist);
1415         }
1416     }
1417
1418   hidden_typelist = typelist;
1419   for (f = sym->formal; f; f = f->next)
1420     if (f->sym != NULL) /* Ignore alternate returns.  */
1421       hidden_typelist = TREE_CHAIN (hidden_typelist);
1422
1423   for (f = sym->formal; f; f = f->next)
1424     {
1425       char name[GFC_MAX_SYMBOL_LEN + 2];
1426
1427       /* Ignore alternate returns.  */
1428       if (f->sym == NULL)
1429         continue;
1430
1431       type = TREE_VALUE (typelist);
1432
1433       if (f->sym->ts.type == BT_CHARACTER)
1434         {
1435           tree len_type = TREE_VALUE (hidden_typelist);
1436           tree length = NULL_TREE;
1437           gcc_assert (len_type == gfc_charlen_type_node);
1438
1439           strcpy (&name[1], f->sym->name);
1440           name[0] = '_';
1441           length = build_decl (PARM_DECL, get_identifier (name), len_type);
1442
1443           hidden_arglist = chainon (hidden_arglist, length);
1444           DECL_CONTEXT (length) = fndecl;
1445           DECL_ARTIFICIAL (length) = 1;
1446           DECL_ARG_TYPE (length) = len_type;
1447           TREE_READONLY (length) = 1;
1448           gfc_finish_decl (length);
1449
1450           /* TODO: Check string lengths when -fbounds-check.  */
1451
1452           /* Use the passed value for assumed length variables.  */
1453           if (!f->sym->ts.cl->length)
1454             {
1455               TREE_USED (length) = 1;
1456               if (!f->sym->ts.cl->backend_decl)
1457                 f->sym->ts.cl->backend_decl = length;
1458               else
1459                 {
1460                   /* there is already another variable using this
1461                      gfc_charlen node, build a new one for this variable
1462                      and chain it into the list of gfc_charlens.
1463                      This happens for e.g. in the case
1464                      CHARACTER(*)::c1,c2
1465                      since CHARACTER declarations on the same line share
1466                      the same gfc_charlen node.  */
1467                   gfc_charlen *cl;
1468
1469                   cl = gfc_get_charlen ();
1470                   cl->backend_decl = length;
1471                   cl->next = f->sym->ts.cl->next;
1472                   f->sym->ts.cl->next = cl;
1473                   f->sym->ts.cl = cl;
1474                 }
1475             }
1476
1477           hidden_typelist = TREE_CHAIN (hidden_typelist);
1478
1479           if (f->sym->ts.cl->backend_decl == NULL
1480               || f->sym->ts.cl->backend_decl == length)
1481             {
1482               if (f->sym->ts.cl->backend_decl == NULL)
1483                 gfc_create_string_length (f->sym);
1484
1485               /* Make sure PARM_DECL type doesn't point to incomplete type.  */
1486               if (f->sym->attr.flavor == FL_PROCEDURE)
1487                 type = build_pointer_type (gfc_get_function_type (f->sym));
1488               else
1489                 type = gfc_sym_type (f->sym);
1490             }
1491         }
1492
1493       /* For non-constant length array arguments, make sure they use
1494          a different type node from TYPE_ARG_TYPES type.  */
1495       if (f->sym->attr.dimension
1496           && type == TREE_VALUE (typelist)
1497           && TREE_CODE (type) == POINTER_TYPE
1498           && GFC_ARRAY_TYPE_P (type)
1499           && f->sym->as->type != AS_ASSUMED_SIZE
1500           && ! COMPLETE_TYPE_P (TREE_TYPE (type)))
1501         {
1502           if (f->sym->attr.flavor == FL_PROCEDURE)
1503             type = build_pointer_type (gfc_get_function_type (f->sym));
1504           else
1505             type = gfc_sym_type (f->sym);
1506         }
1507
1508       /* Build a the argument declaration.  */
1509       parm = build_decl (PARM_DECL, gfc_sym_identifier (f->sym), type);
1510
1511       /* Fill in arg stuff.  */
1512       DECL_CONTEXT (parm) = fndecl;
1513       DECL_ARG_TYPE (parm) = TREE_VALUE (typelist);
1514       /* All implementation args are read-only.  */
1515       TREE_READONLY (parm) = 1;
1516
1517       gfc_finish_decl (parm);
1518
1519       f->sym->backend_decl = parm;
1520
1521       arglist = chainon (arglist, parm);
1522       typelist = TREE_CHAIN (typelist);
1523     }
1524
1525   /* Add the hidden string length parameters.  */
1526   arglist = chainon (arglist, hidden_arglist);
1527
1528   gcc_assert (hidden_typelist == NULL_TREE
1529               || TREE_VALUE (hidden_typelist) == void_type_node);
1530   DECL_ARGUMENTS (fndecl) = arglist;
1531 }
1532
1533 /* Convert FNDECL's code to GIMPLE and handle any nested functions.  */
1534
1535 static void
1536 gfc_gimplify_function (tree fndecl)
1537 {
1538   struct cgraph_node *cgn;
1539
1540   gimplify_function_tree (fndecl);
1541   dump_function (TDI_generic, fndecl);
1542
1543   /* Generate errors for structured block violations.  */
1544   /* ??? Could be done as part of resolve_labels.  */
1545   if (flag_openmp)
1546     diagnose_omp_structured_block_errors (fndecl);
1547
1548   /* Convert all nested functions to GIMPLE now.  We do things in this order
1549      so that items like VLA sizes are expanded properly in the context of the
1550      correct function.  */
1551   cgn = cgraph_node (fndecl);
1552   for (cgn = cgn->nested; cgn; cgn = cgn->next_nested)
1553     gfc_gimplify_function (cgn->decl);
1554 }
1555
1556
1557 /* Do the setup necessary before generating the body of a function.  */
1558
1559 static void
1560 trans_function_start (gfc_symbol * sym)
1561 {
1562   tree fndecl;
1563
1564   fndecl = sym->backend_decl;
1565
1566   /* Let GCC know the current scope is this function.  */
1567   current_function_decl = fndecl;
1568
1569   /* Let the world know what we're about to do.  */
1570   announce_function (fndecl);
1571
1572   if (DECL_CONTEXT (fndecl) == NULL_TREE)
1573     {
1574       /* Create RTL for function declaration.  */
1575       rest_of_decl_compilation (fndecl, 1, 0);
1576     }
1577
1578   /* Create RTL for function definition.  */
1579   make_decl_rtl (fndecl);
1580
1581   init_function_start (fndecl);
1582
1583   /* Even though we're inside a function body, we still don't want to
1584      call expand_expr to calculate the size of a variable-sized array.
1585      We haven't necessarily assigned RTL to all variables yet, so it's
1586      not safe to try to expand expressions involving them.  */
1587   cfun->x_dont_save_pending_sizes_p = 1;
1588
1589   /* function.c requires a push at the start of the function.  */
1590   pushlevel (0);
1591 }
1592
1593 /* Create thunks for alternate entry points.  */
1594
1595 static void
1596 build_entry_thunks (gfc_namespace * ns)
1597 {
1598   gfc_formal_arglist *formal;
1599   gfc_formal_arglist *thunk_formal;
1600   gfc_entry_list *el;
1601   gfc_symbol *thunk_sym;
1602   stmtblock_t body;
1603   tree thunk_fndecl;
1604   tree args;
1605   tree string_args;
1606   tree tmp;
1607   locus old_loc;
1608
1609   /* This should always be a toplevel function.  */
1610   gcc_assert (current_function_decl == NULL_TREE);
1611
1612   gfc_get_backend_locus (&old_loc);
1613   for (el = ns->entries; el; el = el->next)
1614     {
1615       thunk_sym = el->sym;
1616
1617       build_function_decl (thunk_sym);
1618       create_function_arglist (thunk_sym);
1619
1620       trans_function_start (thunk_sym);
1621
1622       thunk_fndecl = thunk_sym->backend_decl;
1623
1624       gfc_start_block (&body);
1625
1626       /* Pass extra parameter identifying this entry point.  */
1627       tmp = build_int_cst (gfc_array_index_type, el->id);
1628       args = tree_cons (NULL_TREE, tmp, NULL_TREE);
1629       string_args = NULL_TREE;
1630
1631       if (thunk_sym->attr.function)
1632         {
1633           if (gfc_return_by_reference (ns->proc_name))
1634             {
1635               tree ref = DECL_ARGUMENTS (current_function_decl);
1636               args = tree_cons (NULL_TREE, ref, args);
1637               if (ns->proc_name->ts.type == BT_CHARACTER)
1638                 args = tree_cons (NULL_TREE, TREE_CHAIN (ref),
1639                                   args);
1640             }
1641         }
1642
1643       for (formal = ns->proc_name->formal; formal; formal = formal->next)
1644         {
1645           /* Ignore alternate returns.  */
1646           if (formal->sym == NULL)
1647             continue;
1648
1649           /* We don't have a clever way of identifying arguments, so resort to
1650              a brute-force search.  */
1651           for (thunk_formal = thunk_sym->formal;
1652                thunk_formal;
1653                thunk_formal = thunk_formal->next)
1654             {
1655               if (thunk_formal->sym == formal->sym)
1656                 break;
1657             }
1658
1659           if (thunk_formal)
1660             {
1661               /* Pass the argument.  */
1662               DECL_ARTIFICIAL (thunk_formal->sym->backend_decl) = 1;
1663               args = tree_cons (NULL_TREE, thunk_formal->sym->backend_decl,
1664                                 args);
1665               if (formal->sym->ts.type == BT_CHARACTER)
1666                 {
1667                   tmp = thunk_formal->sym->ts.cl->backend_decl;
1668                   string_args = tree_cons (NULL_TREE, tmp, string_args);
1669                 }
1670             }
1671           else
1672             {
1673               /* Pass NULL for a missing argument.  */
1674               args = tree_cons (NULL_TREE, null_pointer_node, args);
1675               if (formal->sym->ts.type == BT_CHARACTER)
1676                 {
1677                   tmp = build_int_cst (gfc_charlen_type_node, 0);
1678                   string_args = tree_cons (NULL_TREE, tmp, string_args);
1679                 }
1680             }
1681         }
1682
1683       /* Call the master function.  */
1684       args = nreverse (args);
1685       args = chainon (args, nreverse (string_args));
1686       tmp = ns->proc_name->backend_decl;
1687       tmp = build_function_call_expr (tmp, args);
1688       if (ns->proc_name->attr.mixed_entry_master)
1689         {
1690           tree union_decl, field;
1691           tree master_type = TREE_TYPE (ns->proc_name->backend_decl);
1692
1693           union_decl = build_decl (VAR_DECL, get_identifier ("__result"),
1694                                    TREE_TYPE (master_type));
1695           DECL_ARTIFICIAL (union_decl) = 1;
1696           DECL_EXTERNAL (union_decl) = 0;
1697           TREE_PUBLIC (union_decl) = 0;
1698           TREE_USED (union_decl) = 1;
1699           layout_decl (union_decl, 0);
1700           pushdecl (union_decl);
1701
1702           DECL_CONTEXT (union_decl) = current_function_decl;
1703           tmp = build2 (MODIFY_EXPR,
1704                         TREE_TYPE (union_decl),
1705                         union_decl, tmp);
1706           gfc_add_expr_to_block (&body, tmp);
1707
1708           for (field = TYPE_FIELDS (TREE_TYPE (union_decl));
1709                field; field = TREE_CHAIN (field))
1710             if (strcmp (IDENTIFIER_POINTER (DECL_NAME (field)),
1711                 thunk_sym->result->name) == 0)
1712               break;
1713           gcc_assert (field != NULL_TREE);
1714           tmp = build3 (COMPONENT_REF, TREE_TYPE (field), union_decl, field,
1715                         NULL_TREE);
1716           tmp = build2 (MODIFY_EXPR,
1717                         TREE_TYPE (DECL_RESULT (current_function_decl)),
1718                         DECL_RESULT (current_function_decl), tmp);
1719           tmp = build1_v (RETURN_EXPR, tmp);
1720         }
1721       else if (TREE_TYPE (DECL_RESULT (current_function_decl))
1722                != void_type_node)
1723         {
1724           tmp = build2 (MODIFY_EXPR,
1725                         TREE_TYPE (DECL_RESULT (current_function_decl)),
1726                         DECL_RESULT (current_function_decl), tmp);
1727           tmp = build1_v (RETURN_EXPR, tmp);
1728         }
1729       gfc_add_expr_to_block (&body, tmp);
1730
1731       /* Finish off this function and send it for code generation.  */
1732       DECL_SAVED_TREE (thunk_fndecl) = gfc_finish_block (&body);
1733       poplevel (1, 0, 1);
1734       BLOCK_SUPERCONTEXT (DECL_INITIAL (thunk_fndecl)) = thunk_fndecl;
1735
1736       /* Output the GENERIC tree.  */
1737       dump_function (TDI_original, thunk_fndecl);
1738
1739       /* Store the end of the function, so that we get good line number
1740          info for the epilogue.  */
1741       cfun->function_end_locus = input_location;
1742
1743       /* We're leaving the context of this function, so zap cfun.
1744          It's still in DECL_STRUCT_FUNCTION, and we'll restore it in
1745          tree_rest_of_compilation.  */
1746       cfun = NULL;
1747
1748       current_function_decl = NULL_TREE;
1749
1750       gfc_gimplify_function (thunk_fndecl);
1751       cgraph_finalize_function (thunk_fndecl, false);
1752
1753       /* We share the symbols in the formal argument list with other entry
1754          points and the master function.  Clear them so that they are
1755          recreated for each function.  */
1756       for (formal = thunk_sym->formal; formal; formal = formal->next)
1757         if (formal->sym != NULL)  /* Ignore alternate returns.  */
1758           {
1759             formal->sym->backend_decl = NULL_TREE;
1760             if (formal->sym->ts.type == BT_CHARACTER)
1761               formal->sym->ts.cl->backend_decl = NULL_TREE;
1762           }
1763
1764       if (thunk_sym->attr.function)
1765         {
1766           if (thunk_sym->ts.type == BT_CHARACTER)
1767             thunk_sym->ts.cl->backend_decl = NULL_TREE;
1768           if (thunk_sym->result->ts.type == BT_CHARACTER)
1769             thunk_sym->result->ts.cl->backend_decl = NULL_TREE;
1770         }
1771     }
1772
1773   gfc_set_backend_locus (&old_loc);
1774 }
1775
1776
1777 /* Create a decl for a function, and create any thunks for alternate entry
1778    points.  */
1779
1780 void
1781 gfc_create_function_decl (gfc_namespace * ns)
1782 {
1783   /* Create a declaration for the master function.  */
1784   build_function_decl (ns->proc_name);
1785
1786   /* Compile the entry thunks.  */
1787   if (ns->entries)
1788     build_entry_thunks (ns);
1789
1790   /* Now create the read argument list.  */
1791   create_function_arglist (ns->proc_name);
1792 }
1793
1794 /* Return the decl used to hold the function return value.  If
1795    parent_flag is set, the context is the parent_scope.  */
1796
1797 tree
1798 gfc_get_fake_result_decl (gfc_symbol * sym, int parent_flag)
1799 {
1800   tree decl;
1801   tree length;
1802   tree this_fake_result_decl;
1803   tree this_function_decl;
1804
1805   char name[GFC_MAX_SYMBOL_LEN + 10];
1806
1807   if (parent_flag)
1808     {
1809       this_fake_result_decl = parent_fake_result_decl;
1810       this_function_decl = DECL_CONTEXT (current_function_decl);
1811     }
1812   else
1813     {
1814       this_fake_result_decl = current_fake_result_decl;
1815       this_function_decl = current_function_decl;
1816     }
1817
1818   if (sym
1819       && sym->ns->proc_name->backend_decl == this_function_decl
1820       && sym->ns->proc_name->attr.entry_master
1821       && sym != sym->ns->proc_name)
1822     {
1823       tree t = NULL, var;
1824       if (this_fake_result_decl != NULL)
1825         for (t = TREE_CHAIN (this_fake_result_decl); t; t = TREE_CHAIN (t))
1826           if (strcmp (IDENTIFIER_POINTER (TREE_PURPOSE (t)), sym->name) == 0)
1827             break;
1828       if (t)
1829         return TREE_VALUE (t);
1830       decl = gfc_get_fake_result_decl (sym->ns->proc_name, parent_flag);
1831
1832       if (parent_flag)
1833         this_fake_result_decl = parent_fake_result_decl;
1834       else
1835         this_fake_result_decl = current_fake_result_decl;
1836
1837       if (decl && sym->ns->proc_name->attr.mixed_entry_master)
1838         {
1839           tree field;
1840
1841           for (field = TYPE_FIELDS (TREE_TYPE (decl));
1842                field; field = TREE_CHAIN (field))
1843             if (strcmp (IDENTIFIER_POINTER (DECL_NAME (field)),
1844                 sym->name) == 0)
1845               break;
1846
1847           gcc_assert (field != NULL_TREE);
1848           decl = build3 (COMPONENT_REF, TREE_TYPE (field), decl, field,
1849                          NULL_TREE);
1850         }
1851
1852       var = create_tmp_var_raw (TREE_TYPE (decl), sym->name);
1853       if (parent_flag)
1854         gfc_add_decl_to_parent_function (var);
1855       else
1856         gfc_add_decl_to_function (var);
1857
1858       SET_DECL_VALUE_EXPR (var, decl);
1859       DECL_HAS_VALUE_EXPR_P (var) = 1;
1860       GFC_DECL_RESULT (var) = 1;
1861
1862       TREE_CHAIN (this_fake_result_decl)
1863           = tree_cons (get_identifier (sym->name), var,
1864                        TREE_CHAIN (this_fake_result_decl));
1865       return var;
1866     }
1867
1868   if (this_fake_result_decl != NULL_TREE)
1869     return TREE_VALUE (this_fake_result_decl);
1870
1871   /* Only when gfc_get_fake_result_decl is called by gfc_trans_return,
1872      sym is NULL.  */
1873   if (!sym)
1874     return NULL_TREE;
1875
1876   if (sym->ts.type == BT_CHARACTER)
1877     {
1878       if (sym->ts.cl->backend_decl == NULL_TREE)
1879         length = gfc_create_string_length (sym);
1880       else
1881         length = sym->ts.cl->backend_decl;
1882       if (TREE_CODE (length) == VAR_DECL
1883           && DECL_CONTEXT (length) == NULL_TREE)
1884         gfc_add_decl_to_function (length);
1885     }
1886
1887   if (gfc_return_by_reference (sym))
1888     {
1889       decl = DECL_ARGUMENTS (this_function_decl);
1890
1891       if (sym->ns->proc_name->backend_decl == this_function_decl
1892           && sym->ns->proc_name->attr.entry_master)
1893         decl = TREE_CHAIN (decl);
1894
1895       TREE_USED (decl) = 1;
1896       if (sym->as)
1897         decl = gfc_build_dummy_array_decl (sym, decl);
1898     }
1899   else
1900     {
1901       sprintf (name, "__result_%.20s",
1902                IDENTIFIER_POINTER (DECL_NAME (this_function_decl)));
1903
1904       if (!sym->attr.mixed_entry_master && sym->attr.function)
1905         decl = build_decl (VAR_DECL, get_identifier (name),
1906                            gfc_sym_type (sym));
1907       else
1908         decl = build_decl (VAR_DECL, get_identifier (name),
1909                            TREE_TYPE (TREE_TYPE (this_function_decl)));
1910       DECL_ARTIFICIAL (decl) = 1;
1911       DECL_EXTERNAL (decl) = 0;
1912       TREE_PUBLIC (decl) = 0;
1913       TREE_USED (decl) = 1;
1914       GFC_DECL_RESULT (decl) = 1;
1915       TREE_ADDRESSABLE (decl) = 1;
1916
1917       layout_decl (decl, 0);
1918
1919       if (parent_flag)
1920         gfc_add_decl_to_parent_function (decl);
1921       else
1922         gfc_add_decl_to_function (decl);
1923     }
1924
1925   if (parent_flag)
1926     parent_fake_result_decl = build_tree_list (NULL, decl);
1927   else
1928     current_fake_result_decl = build_tree_list (NULL, decl);
1929
1930   return decl;
1931 }
1932
1933
1934 /* Builds a function decl.  The remaining parameters are the types of the
1935    function arguments.  Negative nargs indicates a varargs function.  */
1936
1937 tree
1938 gfc_build_library_function_decl (tree name, tree rettype, int nargs, ...)
1939 {
1940   tree arglist;
1941   tree argtype;
1942   tree fntype;
1943   tree fndecl;
1944   va_list p;
1945   int n;
1946
1947   /* Library functions must be declared with global scope.  */
1948   gcc_assert (current_function_decl == NULL_TREE);
1949
1950   va_start (p, nargs);
1951
1952
1953   /* Create a list of the argument types.  */
1954   for (arglist = NULL_TREE, n = abs (nargs); n > 0; n--)
1955     {
1956       argtype = va_arg (p, tree);
1957       arglist = gfc_chainon_list (arglist, argtype);
1958     }
1959
1960   if (nargs >= 0)
1961     {
1962       /* Terminate the list.  */
1963       arglist = gfc_chainon_list (arglist, void_type_node);
1964     }
1965
1966   /* Build the function type and decl.  */
1967   fntype = build_function_type (rettype, arglist);
1968   fndecl = build_decl (FUNCTION_DECL, name, fntype);
1969
1970   /* Mark this decl as external.  */
1971   DECL_EXTERNAL (fndecl) = 1;
1972   TREE_PUBLIC (fndecl) = 1;
1973
1974   va_end (p);
1975
1976   pushdecl (fndecl);
1977
1978   rest_of_decl_compilation (fndecl, 1, 0);
1979
1980   return fndecl;
1981 }
1982
1983 static void
1984 gfc_build_intrinsic_function_decls (void)
1985 {
1986   tree gfc_int4_type_node = gfc_get_int_type (4);
1987   tree gfc_int8_type_node = gfc_get_int_type (8);
1988   tree gfc_int16_type_node = gfc_get_int_type (16);
1989   tree gfc_logical4_type_node = gfc_get_logical_type (4);
1990   tree gfc_real4_type_node = gfc_get_real_type (4);
1991   tree gfc_real8_type_node = gfc_get_real_type (8);
1992   tree gfc_real10_type_node = gfc_get_real_type (10);
1993   tree gfc_real16_type_node = gfc_get_real_type (16);
1994   tree gfc_complex4_type_node = gfc_get_complex_type (4);
1995   tree gfc_complex8_type_node = gfc_get_complex_type (8);
1996   tree gfc_complex10_type_node = gfc_get_complex_type (10);
1997   tree gfc_complex16_type_node = gfc_get_complex_type (16);
1998
1999   /* String functions.  */
2000   gfor_fndecl_compare_string =
2001     gfc_build_library_function_decl (get_identifier (PREFIX("compare_string")),
2002                                      integer_type_node, 4,
2003                                      gfc_charlen_type_node, pchar_type_node,
2004                                      gfc_charlen_type_node, pchar_type_node);
2005
2006   gfor_fndecl_concat_string =
2007     gfc_build_library_function_decl (get_identifier (PREFIX("concat_string")),
2008                                      void_type_node,
2009                                      6,
2010                                      gfc_charlen_type_node, pchar_type_node,
2011                                      gfc_charlen_type_node, pchar_type_node,
2012                                      gfc_charlen_type_node, pchar_type_node);
2013
2014   gfor_fndecl_string_len_trim =
2015     gfc_build_library_function_decl (get_identifier (PREFIX("string_len_trim")),
2016                                      gfc_int4_type_node,
2017                                      2, gfc_charlen_type_node,
2018                                      pchar_type_node);
2019
2020   gfor_fndecl_string_index =
2021     gfc_build_library_function_decl (get_identifier (PREFIX("string_index")),
2022                                      gfc_int4_type_node,
2023                                      5, gfc_charlen_type_node, pchar_type_node,
2024                                      gfc_charlen_type_node, pchar_type_node,
2025                                      gfc_logical4_type_node);
2026
2027   gfor_fndecl_string_scan =
2028     gfc_build_library_function_decl (get_identifier (PREFIX("string_scan")),
2029                                      gfc_int4_type_node,
2030                                      5, gfc_charlen_type_node, pchar_type_node,
2031                                      gfc_charlen_type_node, pchar_type_node,
2032                                      gfc_logical4_type_node);
2033
2034   gfor_fndecl_string_verify =
2035     gfc_build_library_function_decl (get_identifier (PREFIX("string_verify")),
2036                                      gfc_int4_type_node,
2037                                      5, gfc_charlen_type_node, pchar_type_node,
2038                                      gfc_charlen_type_node, pchar_type_node,
2039                                      gfc_logical4_type_node);
2040
2041   gfor_fndecl_string_trim =
2042     gfc_build_library_function_decl (get_identifier (PREFIX("string_trim")),
2043                                      void_type_node,
2044                                      4,
2045                                      build_pointer_type (gfc_charlen_type_node),
2046                                      ppvoid_type_node,
2047                                      gfc_charlen_type_node,
2048                                      pchar_type_node);
2049
2050   gfor_fndecl_string_minmax =
2051     gfc_build_library_function_decl (get_identifier (PREFIX("string_minmax")),
2052                                      void_type_node, -4,
2053                                      build_pointer_type (gfc_charlen_type_node),
2054                                      ppvoid_type_node, integer_type_node,
2055                                      integer_type_node);
2056
2057   gfor_fndecl_ttynam =
2058     gfc_build_library_function_decl (get_identifier (PREFIX("ttynam")),
2059                                      void_type_node,
2060                                      3,
2061                                      pchar_type_node,
2062                                      gfc_charlen_type_node,
2063                                      integer_type_node);
2064
2065   gfor_fndecl_fdate =
2066     gfc_build_library_function_decl (get_identifier (PREFIX("fdate")),
2067                                      void_type_node,
2068                                      2,
2069                                      pchar_type_node,
2070                                      gfc_charlen_type_node);
2071
2072   gfor_fndecl_ctime =
2073     gfc_build_library_function_decl (get_identifier (PREFIX("ctime")),
2074                                      void_type_node,
2075                                      3,
2076                                      pchar_type_node,
2077                                      gfc_charlen_type_node,
2078                                      gfc_int8_type_node);
2079
2080   gfor_fndecl_adjustl =
2081     gfc_build_library_function_decl (get_identifier (PREFIX("adjustl")),
2082                                      void_type_node,
2083                                      3,
2084                                      pchar_type_node,
2085                                      gfc_charlen_type_node, pchar_type_node);
2086
2087   gfor_fndecl_adjustr =
2088     gfc_build_library_function_decl (get_identifier (PREFIX("adjustr")),
2089                                      void_type_node,
2090                                      3,
2091                                      pchar_type_node,
2092                                      gfc_charlen_type_node, pchar_type_node);
2093
2094   gfor_fndecl_si_kind =
2095     gfc_build_library_function_decl (get_identifier
2096                                         (PREFIX("selected_int_kind")),
2097                                      gfc_int4_type_node,
2098                                      1,
2099                                      pvoid_type_node);
2100
2101   gfor_fndecl_sr_kind =
2102     gfc_build_library_function_decl (get_identifier
2103                                         (PREFIX("selected_real_kind")),
2104                                      gfc_int4_type_node,
2105                                      2, pvoid_type_node,
2106                                      pvoid_type_node);
2107
2108   /* Power functions.  */
2109   {
2110     tree ctype, rtype, itype, jtype;
2111     int rkind, ikind, jkind;
2112 #define NIKINDS 3
2113 #define NRKINDS 4
2114     static int ikinds[NIKINDS] = {4, 8, 16};
2115     static int rkinds[NRKINDS] = {4, 8, 10, 16};
2116     char name[PREFIX_LEN + 12]; /* _gfortran_pow_?n_?n */
2117
2118     for (ikind=0; ikind < NIKINDS; ikind++)
2119       {
2120         itype = gfc_get_int_type (ikinds[ikind]);
2121
2122         for (jkind=0; jkind < NIKINDS; jkind++)
2123           {
2124             jtype = gfc_get_int_type (ikinds[jkind]);
2125             if (itype && jtype)
2126               {
2127                 sprintf(name, PREFIX("pow_i%d_i%d"), ikinds[ikind],
2128                         ikinds[jkind]);
2129                 gfor_fndecl_math_powi[jkind][ikind].integer =
2130                   gfc_build_library_function_decl (get_identifier (name),
2131                     jtype, 2, jtype, itype);
2132                 TREE_READONLY (gfor_fndecl_math_powi[jkind][ikind].integer) = 1;
2133               }
2134           }
2135
2136         for (rkind = 0; rkind < NRKINDS; rkind ++)
2137           {
2138             rtype = gfc_get_real_type (rkinds[rkind]);
2139             if (rtype && itype)
2140               {
2141                 sprintf(name, PREFIX("pow_r%d_i%d"), rkinds[rkind],
2142                         ikinds[ikind]);
2143                 gfor_fndecl_math_powi[rkind][ikind].real =
2144                   gfc_build_library_function_decl (get_identifier (name),
2145                     rtype, 2, rtype, itype);
2146                 TREE_READONLY (gfor_fndecl_math_powi[rkind][ikind].real) = 1;
2147               }
2148
2149             ctype = gfc_get_complex_type (rkinds[rkind]);
2150             if (ctype && itype)
2151               {
2152                 sprintf(name, PREFIX("pow_c%d_i%d"), rkinds[rkind],
2153                         ikinds[ikind]);
2154                 gfor_fndecl_math_powi[rkind][ikind].cmplx =
2155                   gfc_build_library_function_decl (get_identifier (name),
2156                     ctype, 2,ctype, itype);
2157                 TREE_READONLY (gfor_fndecl_math_powi[rkind][ikind].cmplx) = 1;
2158               }
2159           }
2160       }
2161 #undef NIKINDS
2162 #undef NRKINDS
2163   }
2164
2165   gfor_fndecl_math_cpowf =
2166     gfc_build_library_function_decl (get_identifier ("cpowf"),
2167                                      gfc_complex4_type_node,
2168                                      1, gfc_complex4_type_node);
2169   gfor_fndecl_math_cpow =
2170     gfc_build_library_function_decl (get_identifier ("cpow"),
2171                                      gfc_complex8_type_node,
2172                                      1, gfc_complex8_type_node);
2173   if (gfc_complex10_type_node)
2174     gfor_fndecl_math_cpowl10 =
2175       gfc_build_library_function_decl (get_identifier ("cpowl"),
2176                                        gfc_complex10_type_node, 1,
2177                                        gfc_complex10_type_node);
2178   if (gfc_complex16_type_node)
2179     gfor_fndecl_math_cpowl16 =
2180       gfc_build_library_function_decl (get_identifier ("cpowl"),
2181                                        gfc_complex16_type_node, 1,
2182                                        gfc_complex16_type_node);
2183
2184   gfor_fndecl_math_ishftc4 =
2185     gfc_build_library_function_decl (get_identifier (PREFIX("ishftc4")),
2186                                      gfc_int4_type_node,
2187                                      3, gfc_int4_type_node,
2188                                      gfc_int4_type_node, gfc_int4_type_node);
2189   gfor_fndecl_math_ishftc8 =
2190     gfc_build_library_function_decl (get_identifier (PREFIX("ishftc8")),
2191                                      gfc_int8_type_node,
2192                                      3, gfc_int8_type_node,
2193                                      gfc_int4_type_node, gfc_int4_type_node);
2194   if (gfc_int16_type_node)
2195     gfor_fndecl_math_ishftc16 =
2196       gfc_build_library_function_decl (get_identifier (PREFIX("ishftc16")),
2197                                        gfc_int16_type_node, 3,
2198                                        gfc_int16_type_node,
2199                                        gfc_int4_type_node,
2200                                        gfc_int4_type_node);
2201
2202   gfor_fndecl_math_exponent4 =
2203     gfc_build_library_function_decl (get_identifier (PREFIX("exponent_r4")),
2204                                      gfc_int4_type_node,
2205                                      1, gfc_real4_type_node);
2206   gfor_fndecl_math_exponent8 =
2207     gfc_build_library_function_decl (get_identifier (PREFIX("exponent_r8")),
2208                                      gfc_int4_type_node,
2209                                      1, gfc_real8_type_node);
2210   if (gfc_real10_type_node)
2211     gfor_fndecl_math_exponent10 =
2212       gfc_build_library_function_decl (get_identifier (PREFIX("exponent_r10")),
2213                                        gfc_int4_type_node, 1,
2214                                        gfc_real10_type_node);
2215   if (gfc_real16_type_node)
2216     gfor_fndecl_math_exponent16 =
2217       gfc_build_library_function_decl (get_identifier (PREFIX("exponent_r16")),
2218                                        gfc_int4_type_node, 1,
2219                                        gfc_real16_type_node);
2220
2221   /* BLAS functions.  */
2222   {
2223     tree pint = build_pointer_type (integer_type_node);
2224     tree ps = build_pointer_type (gfc_get_real_type (gfc_default_real_kind));
2225     tree pd = build_pointer_type (gfc_get_real_type (gfc_default_double_kind));
2226     tree pc = build_pointer_type (gfc_get_complex_type (gfc_default_real_kind));
2227     tree pz = build_pointer_type
2228                 (gfc_get_complex_type (gfc_default_double_kind));
2229
2230     gfor_fndecl_sgemm = gfc_build_library_function_decl
2231                           (get_identifier
2232                              (gfc_option.flag_underscoring ? "sgemm_"
2233                                                            : "sgemm"),
2234                            void_type_node, 15, pchar_type_node,
2235                            pchar_type_node, pint, pint, pint, ps, ps, pint,
2236                            ps, pint, ps, ps, pint, integer_type_node,
2237                            integer_type_node);
2238     gfor_fndecl_dgemm = gfc_build_library_function_decl
2239                           (get_identifier
2240                              (gfc_option.flag_underscoring ? "dgemm_"
2241                                                            : "dgemm"),
2242                            void_type_node, 15, pchar_type_node,
2243                            pchar_type_node, pint, pint, pint, pd, pd, pint,
2244                            pd, pint, pd, pd, pint, integer_type_node,
2245                            integer_type_node);
2246     gfor_fndecl_cgemm = gfc_build_library_function_decl
2247                           (get_identifier
2248                              (gfc_option.flag_underscoring ? "cgemm_"
2249                                                            : "cgemm"),
2250                            void_type_node, 15, pchar_type_node,
2251                            pchar_type_node, pint, pint, pint, pc, pc, pint,
2252                            pc, pint, pc, pc, pint, integer_type_node,
2253                            integer_type_node);
2254     gfor_fndecl_zgemm = gfc_build_library_function_decl
2255                           (get_identifier
2256                              (gfc_option.flag_underscoring ? "zgemm_"
2257                                                            : "zgemm"),
2258                            void_type_node, 15, pchar_type_node,
2259                            pchar_type_node, pint, pint, pint, pz, pz, pint,
2260                            pz, pint, pz, pz, pint, integer_type_node,
2261                            integer_type_node);
2262   }
2263
2264   /* Other functions.  */
2265   gfor_fndecl_size0 =
2266     gfc_build_library_function_decl (get_identifier (PREFIX("size0")),
2267                                      gfc_array_index_type,
2268                                      1, pvoid_type_node);
2269   gfor_fndecl_size1 =
2270     gfc_build_library_function_decl (get_identifier (PREFIX("size1")),
2271                                      gfc_array_index_type,
2272                                      2, pvoid_type_node,
2273                                      gfc_array_index_type);
2274
2275   gfor_fndecl_iargc =
2276     gfc_build_library_function_decl (get_identifier (PREFIX ("iargc")),
2277                                      gfc_int4_type_node,
2278                                      0);
2279 }
2280
2281
2282 /* Make prototypes for runtime library functions.  */
2283
2284 void
2285 gfc_build_builtin_function_decls (void)
2286 {
2287   tree gfc_int4_type_node = gfc_get_int_type (4);
2288   tree gfc_pint4_type_node = build_pointer_type (gfc_int4_type_node);
2289
2290   gfor_fndecl_internal_realloc =
2291     gfc_build_library_function_decl (get_identifier
2292                                      (PREFIX("internal_realloc")),
2293                                      pvoid_type_node, 2, pvoid_type_node,
2294                                      gfc_array_index_type);
2295
2296   gfor_fndecl_allocate =
2297     gfc_build_library_function_decl (get_identifier (PREFIX("allocate")),
2298                                      pvoid_type_node, 2,
2299                                      gfc_array_index_type, gfc_pint4_type_node);
2300   DECL_IS_MALLOC (gfor_fndecl_allocate) = 1;
2301
2302   gfor_fndecl_allocate_array =
2303     gfc_build_library_function_decl (get_identifier (PREFIX("allocate_array")),
2304                                      pvoid_type_node, 3, pvoid_type_node,
2305                                      gfc_array_index_type, gfc_pint4_type_node);
2306   DECL_IS_MALLOC (gfor_fndecl_allocate_array) = 1;
2307
2308   gfor_fndecl_deallocate =
2309     gfc_build_library_function_decl (get_identifier (PREFIX("deallocate")),
2310                                      void_type_node, 2, pvoid_type_node,
2311                                      gfc_pint4_type_node);
2312
2313   gfor_fndecl_stop_numeric =
2314     gfc_build_library_function_decl (get_identifier (PREFIX("stop_numeric")),
2315                                      void_type_node, 1, gfc_int4_type_node);
2316
2317   /* Stop doesn't return.  */
2318   TREE_THIS_VOLATILE (gfor_fndecl_stop_numeric) = 1;
2319
2320   gfor_fndecl_stop_string =
2321     gfc_build_library_function_decl (get_identifier (PREFIX("stop_string")),
2322                                      void_type_node, 2, pchar_type_node,
2323                                      gfc_int4_type_node);
2324   /* Stop doesn't return.  */
2325   TREE_THIS_VOLATILE (gfor_fndecl_stop_string) = 1;
2326
2327   gfor_fndecl_pause_numeric =
2328     gfc_build_library_function_decl (get_identifier (PREFIX("pause_numeric")),
2329                                      void_type_node, 1, gfc_int4_type_node);
2330
2331   gfor_fndecl_pause_string =
2332     gfc_build_library_function_decl (get_identifier (PREFIX("pause_string")),
2333                                      void_type_node, 2, pchar_type_node,
2334                                      gfc_int4_type_node);
2335
2336   gfor_fndecl_select_string =
2337     gfc_build_library_function_decl (get_identifier (PREFIX("select_string")),
2338                                      integer_type_node, 0);
2339
2340   gfor_fndecl_runtime_error =
2341     gfc_build_library_function_decl (get_identifier (PREFIX("runtime_error")),
2342                                      void_type_node, -1, pchar_type_node);
2343   /* The runtime_error function does not return.  */
2344   TREE_THIS_VOLATILE (gfor_fndecl_runtime_error) = 1;
2345
2346   gfor_fndecl_runtime_error_at =
2347     gfc_build_library_function_decl (get_identifier (PREFIX("runtime_error_at")),
2348                                      void_type_node, -2, pchar_type_node,
2349                                      pchar_type_node);
2350   /* The runtime_error_at function does not return.  */
2351   TREE_THIS_VOLATILE (gfor_fndecl_runtime_error_at) = 1;
2352
2353   gfor_fndecl_generate_error =
2354     gfc_build_library_function_decl (get_identifier (PREFIX("generate_error")),
2355                                      void_type_node, 3, pvoid_type_node,
2356                                      integer_type_node, pchar_type_node);
2357
2358   gfor_fndecl_os_error =
2359     gfc_build_library_function_decl (get_identifier (PREFIX("os_error")),
2360                                      void_type_node, 1, pchar_type_node);
2361   /* The runtime_error function does not return.  */
2362   TREE_THIS_VOLATILE (gfor_fndecl_os_error) = 1;
2363
2364   gfor_fndecl_set_fpe =
2365     gfc_build_library_function_decl (get_identifier (PREFIX("set_fpe")),
2366                                     void_type_node, 1, integer_type_node);
2367
2368   /* Keep the array dimension in sync with the call, later in this file.  */
2369   gfor_fndecl_set_options =
2370     gfc_build_library_function_decl (get_identifier (PREFIX("set_options")),
2371                                     void_type_node, 2, integer_type_node,
2372                                     pvoid_type_node);
2373
2374   gfor_fndecl_set_convert =
2375     gfc_build_library_function_decl (get_identifier (PREFIX("set_convert")),
2376                                      void_type_node, 1, integer_type_node);
2377
2378   gfor_fndecl_set_record_marker =
2379     gfc_build_library_function_decl (get_identifier (PREFIX("set_record_marker")),
2380                                      void_type_node, 1, integer_type_node);
2381
2382   gfor_fndecl_set_max_subrecord_length =
2383     gfc_build_library_function_decl (get_identifier (PREFIX("set_max_subrecord_length")),
2384                                      void_type_node, 1, integer_type_node);
2385
2386   gfor_fndecl_in_pack = gfc_build_library_function_decl (
2387         get_identifier (PREFIX("internal_pack")),
2388         pvoid_type_node, 1, pvoid_type_node);
2389
2390   gfor_fndecl_in_unpack = gfc_build_library_function_decl (
2391         get_identifier (PREFIX("internal_unpack")),
2392         pvoid_type_node, 1, pvoid_type_node);
2393
2394   gfor_fndecl_associated =
2395     gfc_build_library_function_decl (
2396                                      get_identifier (PREFIX("associated")),
2397                                      integer_type_node, 2, ppvoid_type_node,
2398                                      ppvoid_type_node);
2399
2400   gfc_build_intrinsic_function_decls ();
2401   gfc_build_intrinsic_lib_fndecls ();
2402   gfc_build_io_library_fndecls ();
2403 }
2404
2405
2406 /* Evaluate the length of dummy character variables.  */
2407
2408 static tree
2409 gfc_trans_dummy_character (gfc_symbol *sym, gfc_charlen *cl, tree fnbody)
2410 {
2411   stmtblock_t body;
2412
2413   gfc_finish_decl (cl->backend_decl);
2414
2415   gfc_start_block (&body);
2416
2417   /* Evaluate the string length expression.  */
2418   gfc_trans_init_string_length (cl, &body);
2419
2420   gfc_trans_vla_type_sizes (sym, &body);
2421
2422   gfc_add_expr_to_block (&body, fnbody);
2423   return gfc_finish_block (&body);
2424 }
2425
2426
2427 /* Allocate and cleanup an automatic character variable.  */
2428
2429 static tree
2430 gfc_trans_auto_character_variable (gfc_symbol * sym, tree fnbody)
2431 {
2432   stmtblock_t body;
2433   tree decl;
2434   tree tmp;
2435
2436   gcc_assert (sym->backend_decl);
2437   gcc_assert (sym->ts.cl && sym->ts.cl->length);
2438
2439   gfc_start_block (&body);
2440
2441   /* Evaluate the string length expression.  */
2442   gfc_trans_init_string_length (sym->ts.cl, &body);
2443
2444   gfc_trans_vla_type_sizes (sym, &body);
2445
2446   decl = sym->backend_decl;
2447
2448   /* Emit a DECL_EXPR for this variable, which will cause the
2449      gimplifier to allocate storage, and all that good stuff.  */
2450   tmp = build1 (DECL_EXPR, TREE_TYPE (decl), decl);
2451   gfc_add_expr_to_block (&body, tmp);
2452
2453   gfc_add_expr_to_block (&body, fnbody);
2454   return gfc_finish_block (&body);
2455 }
2456
2457 /* Set the initial value of ASSIGN statement auxiliary variable explicitly.  */
2458
2459 static tree
2460 gfc_trans_assign_aux_var (gfc_symbol * sym, tree fnbody)
2461 {
2462   stmtblock_t body;
2463
2464   gcc_assert (sym->backend_decl);
2465   gfc_start_block (&body);
2466
2467   /* Set the initial value to length. See the comments in
2468      function gfc_add_assign_aux_vars in this file.  */
2469   gfc_add_modify_expr (&body, GFC_DECL_STRING_LEN (sym->backend_decl),
2470                        build_int_cst (NULL_TREE, -2));
2471
2472   gfc_add_expr_to_block (&body, fnbody);
2473   return gfc_finish_block (&body);
2474 }
2475
2476 static void
2477 gfc_trans_vla_one_sizepos (tree *tp, stmtblock_t *body)
2478 {
2479   tree t = *tp, var, val;
2480
2481   if (t == NULL || t == error_mark_node)
2482     return;
2483   if (TREE_CONSTANT (t) || DECL_P (t))
2484     return;
2485
2486   if (TREE_CODE (t) == SAVE_EXPR)
2487     {
2488       if (SAVE_EXPR_RESOLVED_P (t))
2489         {
2490           *tp = TREE_OPERAND (t, 0);
2491           return;
2492         }
2493       val = TREE_OPERAND (t, 0);
2494     }
2495   else
2496     val = t;
2497
2498   var = gfc_create_var_np (TREE_TYPE (t), NULL);
2499   gfc_add_decl_to_function (var);
2500   gfc_add_modify_expr (body, var, val);
2501   if (TREE_CODE (t) == SAVE_EXPR)
2502     TREE_OPERAND (t, 0) = var;
2503   *tp = var;
2504 }
2505
2506 static void
2507 gfc_trans_vla_type_sizes_1 (tree type, stmtblock_t *body)
2508 {
2509   tree t;
2510
2511   if (type == NULL || type == error_mark_node)
2512     return;
2513
2514   type = TYPE_MAIN_VARIANT (type);
2515
2516   if (TREE_CODE (type) == INTEGER_TYPE)
2517     {
2518       gfc_trans_vla_one_sizepos (&TYPE_MIN_VALUE (type), body);
2519       gfc_trans_vla_one_sizepos (&TYPE_MAX_VALUE (type), body);
2520
2521       for (t = TYPE_NEXT_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t))
2522         {
2523           TYPE_MIN_VALUE (t) = TYPE_MIN_VALUE (type);
2524           TYPE_MAX_VALUE (t) = TYPE_MAX_VALUE (type);
2525         }
2526     }
2527   else if (TREE_CODE (type) == ARRAY_TYPE)
2528     {
2529       gfc_trans_vla_type_sizes_1 (TREE_TYPE (type), body);
2530       gfc_trans_vla_type_sizes_1 (TYPE_DOMAIN (type), body);
2531       gfc_trans_vla_one_sizepos (&TYPE_SIZE (type), body);
2532       gfc_trans_vla_one_sizepos (&TYPE_SIZE_UNIT (type), body);
2533
2534       for (t = TYPE_NEXT_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t))
2535         {
2536           TYPE_SIZE (t) = TYPE_SIZE (type);
2537           TYPE_SIZE_UNIT (t) = TYPE_SIZE_UNIT (type);
2538         }
2539     }
2540 }
2541
2542 /* Make sure all type sizes and array domains are either constant,
2543    or variable or parameter decls.  This is a simplified variant
2544    of gimplify_type_sizes, but we can't use it here, as none of the
2545    variables in the expressions have been gimplified yet.
2546    As type sizes and domains for various variable length arrays
2547    contain VAR_DECLs that are only initialized at gfc_trans_deferred_vars
2548    time, without this routine gimplify_type_sizes in the middle-end
2549    could result in the type sizes being gimplified earlier than where
2550    those variables are initialized.  */
2551
2552 void
2553 gfc_trans_vla_type_sizes (gfc_symbol *sym, stmtblock_t *body)
2554 {
2555   tree type = TREE_TYPE (sym->backend_decl);
2556
2557   if (TREE_CODE (type) == FUNCTION_TYPE
2558       && (sym->attr.function || sym->attr.result || sym->attr.entry))
2559     {
2560       if (! current_fake_result_decl)
2561         return;
2562
2563       type = TREE_TYPE (TREE_VALUE (current_fake_result_decl));
2564     }
2565
2566   while (POINTER_TYPE_P (type))
2567     type = TREE_TYPE (type);
2568
2569   if (GFC_DESCRIPTOR_TYPE_P (type))
2570     {
2571       tree etype = GFC_TYPE_ARRAY_DATAPTR_TYPE (type);
2572
2573       while (POINTER_TYPE_P (etype))
2574         etype = TREE_TYPE (etype);
2575
2576       gfc_trans_vla_type_sizes_1 (etype, body);
2577     }
2578
2579   gfc_trans_vla_type_sizes_1 (type, body);
2580 }
2581
2582
2583 /* Generate function entry and exit code, and add it to the function body.
2584    This includes:
2585     Allocation and initialization of array variables.
2586     Allocation of character string variables.
2587     Initialization and possibly repacking of dummy arrays.
2588     Initialization of ASSIGN statement auxiliary variable.  */
2589
2590 static tree
2591 gfc_trans_deferred_vars (gfc_symbol * proc_sym, tree fnbody)
2592 {
2593   locus loc;
2594   gfc_symbol *sym;
2595   gfc_formal_arglist *f;
2596   stmtblock_t body;
2597   bool seen_trans_deferred_array = false;
2598
2599   /* Deal with implicit return variables.  Explicit return variables will
2600      already have been added.  */
2601   if (gfc_return_by_reference (proc_sym) && proc_sym->result == proc_sym)
2602     {
2603       if (!current_fake_result_decl)
2604         {
2605           gfc_entry_list *el = NULL;
2606           if (proc_sym->attr.entry_master)
2607             {
2608               for (el = proc_sym->ns->entries; el; el = el->next)
2609                 if (el->sym != el->sym->result)
2610                   break;
2611             }
2612           if (el == NULL)
2613             warning (0, "Function does not return a value");
2614         }
2615       else if (proc_sym->as)
2616         {
2617           tree result = TREE_VALUE (current_fake_result_decl);
2618           fnbody = gfc_trans_dummy_array_bias (proc_sym, result, fnbody);
2619
2620           /* An automatic character length, pointer array result.  */
2621           if (proc_sym->ts.type == BT_CHARACTER
2622                 && TREE_CODE (proc_sym->ts.cl->backend_decl) == VAR_DECL)
2623             fnbody = gfc_trans_dummy_character (proc_sym, proc_sym->ts.cl,
2624                                                 fnbody);
2625         }
2626       else if (proc_sym->ts.type == BT_CHARACTER)
2627         {
2628           if (TREE_CODE (proc_sym->ts.cl->backend_decl) == VAR_DECL)
2629             fnbody = gfc_trans_dummy_character (proc_sym, proc_sym->ts.cl,
2630                                                 fnbody);
2631         }
2632       else
2633         gcc_assert (gfc_option.flag_f2c
2634                     && proc_sym->ts.type == BT_COMPLEX);
2635     }
2636
2637   for (sym = proc_sym->tlink; sym != proc_sym; sym = sym->tlink)
2638     {
2639       bool sym_has_alloc_comp = (sym->ts.type == BT_DERIVED)
2640                                    && sym->ts.derived->attr.alloc_comp;
2641       if (sym->attr.dimension)
2642         {
2643           switch (sym->as->type)
2644             {
2645             case AS_EXPLICIT:
2646               if (sym->attr.dummy || sym->attr.result)
2647                 fnbody =
2648                   gfc_trans_dummy_array_bias (sym, sym->backend_decl, fnbody);
2649               else if (sym->attr.pointer || sym->attr.allocatable)
2650                 {
2651                   if (TREE_STATIC (sym->backend_decl))
2652                     gfc_trans_static_array_pointer (sym);
2653                   else
2654                     {
2655                       seen_trans_deferred_array = true;
2656                       fnbody = gfc_trans_deferred_array (sym, fnbody);
2657                     }
2658                 }
2659               else
2660                 {
2661                   if (sym_has_alloc_comp)
2662                     {
2663                       seen_trans_deferred_array = true;
2664                       fnbody = gfc_trans_deferred_array (sym, fnbody);
2665                     }
2666
2667                   gfc_get_backend_locus (&loc);
2668                   gfc_set_backend_locus (&sym->declared_at);
2669                   fnbody = gfc_trans_auto_array_allocation (sym->backend_decl,
2670                       sym, fnbody);
2671                   gfc_set_backend_locus (&loc);
2672                 }
2673               break;
2674
2675             case AS_ASSUMED_SIZE:
2676               /* Must be a dummy parameter.  */
2677               gcc_assert (sym->attr.dummy);
2678
2679               /* We should always pass assumed size arrays the g77 way.  */
2680               fnbody = gfc_trans_g77_array (sym, fnbody);
2681               break;
2682
2683             case AS_ASSUMED_SHAPE:
2684               /* Must be a dummy parameter.  */
2685               gcc_assert (sym->attr.dummy);
2686
2687               fnbody = gfc_trans_dummy_array_bias (sym, sym->backend_decl,
2688                                                    fnbody);
2689               break;
2690
2691             case AS_DEFERRED:
2692               seen_trans_deferred_array = true;
2693               fnbody = gfc_trans_deferred_array (sym, fnbody);
2694               break;
2695
2696             default:
2697               gcc_unreachable ();
2698             }
2699           if (sym_has_alloc_comp && !seen_trans_deferred_array)
2700             fnbody = gfc_trans_deferred_array (sym, fnbody);
2701         }
2702       else if (sym_has_alloc_comp)
2703         fnbody = gfc_trans_deferred_array (sym, fnbody);
2704       else if (sym->ts.type == BT_CHARACTER)
2705         {
2706           gfc_get_backend_locus (&loc);
2707           gfc_set_backend_locus (&sym->declared_at);
2708           if (sym->attr.dummy || sym->attr.result)
2709             fnbody = gfc_trans_dummy_character (sym, sym->ts.cl, fnbody);
2710           else
2711             fnbody = gfc_trans_auto_character_variable (sym, fnbody);
2712           gfc_set_backend_locus (&loc);
2713         }
2714       else if (sym->attr.assign)
2715         {
2716           gfc_get_backend_locus (&loc);
2717           gfc_set_backend_locus (&sym->declared_at);
2718           fnbody = gfc_trans_assign_aux_var (sym, fnbody);
2719           gfc_set_backend_locus (&loc);
2720         }
2721       else
2722         gcc_unreachable ();
2723     }
2724
2725   gfc_init_block (&body);
2726
2727   for (f = proc_sym->formal; f; f = f->next)
2728     {
2729       if (f->sym && f->sym->tlink == NULL && f->sym->ts.type == BT_CHARACTER)
2730         {
2731           gcc_assert (f->sym->ts.cl->backend_decl != NULL);
2732           if (TREE_CODE (f->sym->ts.cl->backend_decl) == PARM_DECL)
2733             gfc_trans_vla_type_sizes (f->sym, &body);
2734         }
2735
2736       /* If an INTENT(OUT) dummy of derived type has a default
2737          initializer, it must be initialized here.  */
2738       if (f->sym && f->sym->attr.intent == INTENT_OUT
2739             && f->sym->ts.type == BT_DERIVED
2740             && !f->sym->ts.derived->attr.alloc_comp
2741             && f->sym->value)
2742         {
2743           gfc_expr *tmpe;
2744           tree tmp, present;
2745           gcc_assert (!f->sym->attr.allocatable);
2746           gfc_set_sym_referenced (f->sym);
2747           tmpe = gfc_lval_expr_from_sym (f->sym);
2748           tmp = gfc_trans_assignment (tmpe, f->sym->value, false);
2749
2750           present = gfc_conv_expr_present (f->sym);
2751           tmp = build3 (COND_EXPR, TREE_TYPE (tmp), present,
2752                         tmp, build_empty_stmt ());
2753           gfc_add_expr_to_block (&body, tmp);
2754           gfc_free_expr (tmpe);
2755         }
2756     }
2757
2758   if (gfc_return_by_reference (proc_sym) && proc_sym->ts.type == BT_CHARACTER
2759       && current_fake_result_decl != NULL)
2760     {
2761       gcc_assert (proc_sym->ts.cl->backend_decl != NULL);
2762       if (TREE_CODE (proc_sym->ts.cl->backend_decl) == PARM_DECL)
2763         gfc_trans_vla_type_sizes (proc_sym, &body);
2764     }
2765
2766   gfc_add_expr_to_block (&body, fnbody);
2767   return gfc_finish_block (&body);
2768 }
2769
2770
2771 /* Output an initialized decl for a module variable.  */
2772
2773 static void
2774 gfc_create_module_variable (gfc_symbol * sym)
2775 {
2776   tree decl;
2777
2778   /* Module functions with alternate entries are dealt with later and
2779      would get caught by the next condition.  */
2780   if (sym->attr.entry)
2781     return;
2782
2783   /* Make sure we convert the types of the derived types from iso_c_binding
2784      into (void *).  */
2785   if (sym->attr.flavor != FL_PROCEDURE && sym->attr.is_iso_c
2786       && sym->ts.type == BT_DERIVED)
2787     sym->backend_decl = gfc_typenode_for_spec (&(sym->ts));
2788
2789   /* Only output variables and array valued parameters.  */
2790   if (sym->attr.flavor != FL_VARIABLE
2791       && (sym->attr.flavor != FL_PARAMETER || sym->attr.dimension == 0))
2792     return;
2793
2794   /* Don't generate variables from other modules. Variables from
2795      COMMONs will already have been generated.  */
2796   if (sym->attr.use_assoc || sym->attr.in_common)
2797     return;
2798
2799   /* Equivalenced variables arrive here after creation.  */
2800   if (sym->backend_decl
2801         && (sym->equiv_built || sym->attr.in_equivalence))
2802       return;
2803
2804   if (sym->backend_decl)
2805     internal_error ("backend decl for module variable %s already exists",
2806                     sym->name);
2807
2808   /* We always want module variables to be created.  */
2809   sym->attr.referenced = 1;
2810   /* Create the decl.  */
2811   decl = gfc_get_symbol_decl (sym);
2812
2813   /* Create the variable.  */
2814   pushdecl (decl);
2815   rest_of_decl_compilation (decl, 1, 0);
2816
2817   /* Also add length of strings.  */
2818   if (sym->ts.type == BT_CHARACTER)
2819     {
2820       tree length;
2821
2822       length = sym->ts.cl->backend_decl;
2823       if (!INTEGER_CST_P (length))
2824         {
2825           pushdecl (length);
2826           rest_of_decl_compilation (length, 1, 0);
2827         }
2828     }
2829 }
2830
2831
2832 /* Generate all the required code for module variables.  */
2833
2834 void
2835 gfc_generate_module_vars (gfc_namespace * ns)
2836 {
2837   module_namespace = ns;
2838
2839   /* Check if the frontend left the namespace in a reasonable state.  */
2840   gcc_assert (ns->proc_name && !ns->proc_name->tlink);
2841
2842   /* Generate COMMON blocks.  */
2843   gfc_trans_common (ns);
2844
2845   /* Create decls for all the module variables.  */
2846   gfc_traverse_ns (ns, gfc_create_module_variable);
2847 }
2848
2849 static void
2850 gfc_generate_contained_functions (gfc_namespace * parent)
2851 {
2852   gfc_namespace *ns;
2853
2854   /* We create all the prototypes before generating any code.  */
2855   for (ns = parent->contained; ns; ns = ns->sibling)
2856     {
2857       /* Skip namespaces from used modules.  */
2858       if (ns->parent != parent)
2859         continue;
2860
2861       gfc_create_function_decl (ns);
2862     }
2863
2864   for (ns = parent->contained; ns; ns = ns->sibling)
2865     {
2866       /* Skip namespaces from used modules.  */
2867       if (ns->parent != parent)
2868         continue;
2869
2870       gfc_generate_function_code (ns);
2871     }
2872 }
2873
2874
2875 /* Drill down through expressions for the array specification bounds and
2876    character length calling generate_local_decl for all those variables
2877    that have not already been declared.  */
2878
2879 static void
2880 generate_local_decl (gfc_symbol *);
2881
2882 static void
2883 generate_expr_decls (gfc_symbol *sym, gfc_expr *e)
2884 {
2885   gfc_actual_arglist *arg;
2886   gfc_ref *ref;
2887   int i;
2888
2889   if (e == NULL)
2890     return;
2891
2892   switch (e->expr_type)
2893     {
2894     case EXPR_FUNCTION:
2895       for (arg = e->value.function.actual; arg; arg = arg->next)
2896         generate_expr_decls (sym, arg->expr);
2897       break;
2898
2899     /* If the variable is not the same as the dependent, 'sym', and
2900        it is not marked as being declared and it is in the same
2901        namespace as 'sym', add it to the local declarations.  */
2902     case EXPR_VARIABLE:
2903       if (sym == e->symtree->n.sym
2904             || e->symtree->n.sym->mark
2905             || e->symtree->n.sym->ns != sym->ns)
2906         return;
2907
2908       generate_local_decl (e->symtree->n.sym);
2909       break;
2910
2911     case EXPR_OP:
2912       generate_expr_decls (sym, e->value.op.op1);
2913       generate_expr_decls (sym, e->value.op.op2);
2914       break;
2915
2916     default:
2917       break;
2918     }
2919
2920   if (e->ref)
2921     {
2922       for (ref = e->ref; ref; ref = ref->next)
2923         {
2924           switch (ref->type)
2925             {
2926             case REF_ARRAY:
2927               for (i = 0; i < ref->u.ar.dimen; i++)
2928                 {
2929                   generate_expr_decls (sym, ref->u.ar.start[i]);
2930                   generate_expr_decls (sym, ref->u.ar.end[i]);
2931                   generate_expr_decls (sym, ref->u.ar.stride[i]);
2932                 }
2933               break;
2934
2935             case REF_SUBSTRING:
2936               generate_expr_decls (sym, ref->u.ss.start);
2937               generate_expr_decls (sym, ref->u.ss.end);
2938               break;
2939
2940             case REF_COMPONENT:
2941               if (ref->u.c.component->ts.type == BT_CHARACTER
2942                     && ref->u.c.component->ts.cl->length->expr_type
2943                                                 != EXPR_CONSTANT)
2944                 generate_expr_decls (sym, ref->u.c.component->ts.cl->length);
2945
2946               if (ref->u.c.component->as)
2947                 for (i = 0; i < ref->u.c.component->as->rank; i++)
2948                   {
2949                     generate_expr_decls (sym, ref->u.c.component->as->lower[i]);
2950                     generate_expr_decls (sym, ref->u.c.component->as->upper[i]);
2951                   }
2952               break;
2953             }
2954         }
2955     }
2956 }
2957
2958
2959 /* Check for dependencies in the character length and array spec.  */
2960
2961 static void
2962 generate_dependency_declarations (gfc_symbol *sym)
2963 {
2964   int i;
2965
2966   if (sym->ts.type == BT_CHARACTER
2967         && sym->ts.cl->length->expr_type != EXPR_CONSTANT)
2968     generate_expr_decls (sym, sym->ts.cl->length);
2969
2970   if (sym->as && sym->as->rank)
2971     {
2972       for (i = 0; i < sym->as->rank; i++)
2973         {
2974           generate_expr_decls (sym, sym->as->lower[i]);
2975           generate_expr_decls (sym, sym->as->upper[i]);
2976         }
2977     }
2978 }
2979
2980
2981 /* Generate decls for all local variables.  We do this to ensure correct
2982    handling of expressions which only appear in the specification of
2983    other functions.  */
2984
2985 static void
2986 generate_local_decl (gfc_symbol * sym)
2987 {
2988   if (sym->attr.flavor == FL_VARIABLE)
2989     {
2990       /* Check for dependencies in the array specification and string
2991         length, adding the necessary declarations to the function.  We
2992         mark the symbol now, as well as in traverse_ns, to prevent
2993         getting stuck in a circular dependency.  */
2994       sym->mark = 1;
2995       if (!sym->attr.dummy && !sym->ns->proc_name->attr.entry_master)
2996         generate_dependency_declarations (sym);
2997
2998       if (sym->attr.referenced)
2999         gfc_get_symbol_decl (sym);
3000       /* INTENT(out) dummy arguments are likely meant to be set.  */
3001       else if (warn_unused_variable
3002                && sym->attr.dummy
3003                && sym->attr.intent == INTENT_OUT)
3004         gfc_warning ("Dummy argument '%s' at %L was declared INTENT(OUT) but was not set",
3005                      sym->name, &sym->declared_at);
3006       /* Specific warning for unused dummy arguments. */
3007       else if (warn_unused_variable && sym->attr.dummy)
3008         gfc_warning ("Unused dummy argument '%s' at %L", sym->name,
3009                      &sym->declared_at);
3010       /* Warn for unused variables, but not if they're inside a common
3011          block or are use-associated.  */
3012       else if (warn_unused_variable
3013                && !(sym->attr.in_common || sym->attr.use_assoc))
3014         gfc_warning ("Unused variable '%s' declared at %L", sym->name,
3015                      &sym->declared_at);
3016       /* For variable length CHARACTER parameters, the PARM_DECL already
3017          references the length variable, so force gfc_get_symbol_decl
3018          even when not referenced.  If optimize > 0, it will be optimized
3019          away anyway.  But do this only after emitting -Wunused-parameter
3020          warning if requested.  */
3021       if (sym->attr.dummy && ! sym->attr.referenced
3022           && sym->ts.type == BT_CHARACTER
3023           && sym->ts.cl->backend_decl != NULL
3024           && TREE_CODE (sym->ts.cl->backend_decl) == VAR_DECL)
3025         {
3026           sym->attr.referenced = 1;
3027           gfc_get_symbol_decl (sym);
3028         }
3029
3030       /* We do not want the middle-end to warn about unused parameters
3031          as this was already done above.  */
3032       if (sym->attr.dummy && sym->backend_decl != NULL_TREE)
3033           TREE_NO_WARNING(sym->backend_decl) = 1;
3034     }
3035   else if (sym->attr.flavor == FL_PARAMETER)
3036     {
3037       if (warn_unused_parameter
3038            && !sym->attr.referenced
3039            && !sym->attr.use_assoc)
3040         gfc_warning ("Unused parameter '%s' declared at %L", sym->name,
3041                      &sym->declared_at);
3042     }
3043
3044   if (sym->attr.dummy == 1)
3045     {
3046       /* Modify the tree type for scalar character dummy arguments of bind(c)
3047          procedures if they are passed by value.  The tree type for them will
3048          be promoted to INTEGER_TYPE for the middle end, which appears to be
3049          what C would do with characters passed by-value.  The value attribute
3050          implies the dummy is a scalar.  */
3051       if (sym->attr.value == 1 && sym->backend_decl != NULL
3052           && sym->ts.type == BT_CHARACTER && sym->ts.is_c_interop
3053           && sym->ns->proc_name != NULL && sym->ns->proc_name->attr.is_bind_c)
3054         gfc_conv_scalar_char_value (sym, NULL, NULL);
3055     }
3056
3057   /* Make sure we convert the types of the derived types from iso_c_binding
3058      into (void *).  */
3059   if (sym->attr.flavor != FL_PROCEDURE && sym->attr.is_iso_c
3060       && sym->ts.type == BT_DERIVED)
3061     sym->backend_decl = gfc_typenode_for_spec (&(sym->ts));
3062 }
3063
3064 static void
3065 generate_local_vars (gfc_namespace * ns)
3066 {
3067   gfc_traverse_ns (ns, generate_local_decl);
3068 }
3069
3070
3071 /* Generate a switch statement to jump to the correct entry point.  Also
3072    creates the label decls for the entry points.  */
3073
3074 static tree
3075 gfc_trans_entry_master_switch (gfc_entry_list * el)
3076 {
3077   stmtblock_t block;
3078   tree label;
3079   tree tmp;
3080   tree val;
3081
3082   gfc_init_block (&block);
3083   for (; el; el = el->next)
3084     {
3085       /* Add the case label.  */
3086       label = gfc_build_label_decl (NULL_TREE);
3087       val = build_int_cst (gfc_array_index_type, el->id);
3088       tmp = build3_v (CASE_LABEL_EXPR, val, NULL_TREE, label);
3089       gfc_add_expr_to_block (&block, tmp);
3090
3091       /* And jump to the actual entry point.  */
3092       label = gfc_build_label_decl (NULL_TREE);
3093       tmp = build1_v (GOTO_EXPR, label);
3094       gfc_add_expr_to_block (&block, tmp);
3095
3096       /* Save the label decl.  */
3097       el->label = label;
3098     }
3099   tmp = gfc_finish_block (&block);
3100   /* The first argument selects the entry point.  */
3101   val = DECL_ARGUMENTS (current_function_decl);
3102   tmp = build3_v (SWITCH_EXPR, val, tmp, NULL_TREE);
3103   return tmp;
3104 }
3105
3106
3107 /* Generate code for a function.  */
3108
3109 void
3110 gfc_generate_function_code (gfc_namespace * ns)
3111 {
3112   tree fndecl;
3113   tree old_context;
3114   tree decl;
3115   tree tmp;
3116   tree tmp2;
3117   stmtblock_t block;
3118   stmtblock_t body;
3119   tree result;
3120   gfc_symbol *sym;
3121   int rank;
3122
3123   sym = ns->proc_name;
3124
3125   /* Check that the frontend isn't still using this.  */
3126   gcc_assert (sym->tlink == NULL);
3127   sym->tlink = sym;
3128
3129   /* Create the declaration for functions with global scope.  */
3130   if (!sym->backend_decl)
3131     gfc_create_function_decl (ns);
3132
3133   fndecl = sym->backend_decl;
3134   old_context = current_function_decl;
3135
3136   if (old_context)
3137     {
3138       push_function_context ();
3139       saved_parent_function_decls = saved_function_decls;
3140       saved_function_decls = NULL_TREE;
3141     }
3142
3143   trans_function_start (sym);
3144
3145   gfc_start_block (&block);
3146
3147   if (ns->entries && ns->proc_name->ts.type == BT_CHARACTER)
3148     {
3149       /* Copy length backend_decls to all entry point result
3150          symbols.  */
3151       gfc_entry_list *el;
3152       tree backend_decl;
3153
3154       gfc_conv_const_charlen (ns->proc_name->ts.cl);
3155       backend_decl = ns->proc_name->result->ts.cl->backend_decl;
3156       for (el = ns->entries; el; el = el->next)
3157         el->sym->result->ts.cl->backend_decl = backend_decl;
3158     }
3159
3160   /* Translate COMMON blocks.  */
3161   gfc_trans_common (ns);
3162
3163   /* Null the parent fake result declaration if this namespace is
3164      a module function or an external procedures.  */
3165   if ((ns->parent && ns->parent->proc_name->attr.flavor == FL_MODULE)
3166         || ns->parent == NULL)
3167     parent_fake_result_decl = NULL_TREE;
3168
3169   gfc_generate_contained_functions (ns);
3170
3171   generate_local_vars (ns);
3172
3173   /* Keep the parent fake result declaration in module functions
3174      or external procedures.  */
3175   if ((ns->parent && ns->parent->proc_name->attr.flavor == FL_MODULE)
3176         || ns->parent == NULL)
3177     current_fake_result_decl = parent_fake_result_decl;
3178   else
3179     current_fake_result_decl = NULL_TREE;
3180
3181   current_function_return_label = NULL;
3182
3183   /* Now generate the code for the body of this function.  */
3184   gfc_init_block (&body);
3185
3186   /* If this is the main program, add a call to set_options to set up the
3187      runtime library Fortran language standard parameters.  */
3188   if (sym->attr.is_main_program)
3189     {
3190       tree array_type, array, var;
3191
3192       /* Passing a new option to the library requires four modifications:
3193            + add it to the tree_cons list below
3194            + change the array size in the call to build_array_type
3195            + change the first argument to the library call
3196              gfor_fndecl_set_options
3197            + modify the library (runtime/compile_options.c)!  */
3198       array = tree_cons (NULL_TREE,
3199                          build_int_cst (integer_type_node,
3200                                         gfc_option.warn_std), NULL_TREE);
3201       array = tree_cons (NULL_TREE,
3202                          build_int_cst (integer_type_node,
3203                                         gfc_option.allow_std), array);
3204       array = tree_cons (NULL_TREE,
3205                          build_int_cst (integer_type_node, pedantic), array);
3206       array = tree_cons (NULL_TREE,
3207                          build_int_cst (integer_type_node,
3208                                         gfc_option.flag_dump_core), array);
3209       array = tree_cons (NULL_TREE,
3210                          build_int_cst (integer_type_node,
3211                                         gfc_option.flag_backtrace), array);
3212       array = tree_cons (NULL_TREE,
3213                          build_int_cst (integer_type_node,
3214                                         gfc_option.flag_sign_zero), array);
3215
3216       array = tree_cons (NULL_TREE,
3217                          build_int_cst (integer_type_node,
3218                                         flag_bounds_check), array);
3219
3220       array_type = build_array_type (integer_type_node,
3221                                      build_index_type (build_int_cst (NULL_TREE,
3222                                                                       6)));
3223       array = build_constructor_from_list (array_type, nreverse (array));
3224       TREE_CONSTANT (array) = 1;
3225       TREE_INVARIANT (array) = 1;
3226       TREE_STATIC (array) = 1;
3227
3228       /* Create a static variable to hold the jump table.  */
3229       var = gfc_create_var (array_type, "options");
3230       TREE_CONSTANT (var) = 1;
3231       TREE_INVARIANT (var) = 1;
3232       TREE_STATIC (var) = 1;
3233       TREE_READONLY (var) = 1;
3234       DECL_INITIAL (var) = array;
3235       var = gfc_build_addr_expr (pvoid_type_node, var);
3236
3237       tmp = build_call_expr (gfor_fndecl_set_options, 2,
3238                              build_int_cst (integer_type_node, 7), var);
3239       gfc_add_expr_to_block (&body, tmp);
3240     }
3241
3242   /* If this is the main program and a -ffpe-trap option was provided,
3243      add a call to set_fpe so that the library will raise a FPE when
3244      needed.  */
3245   if (sym->attr.is_main_program && gfc_option.fpe != 0)
3246     {
3247       tmp = build_call_expr (gfor_fndecl_set_fpe, 1,
3248                              build_int_cst (integer_type_node,
3249                                             gfc_option.fpe));
3250       gfc_add_expr_to_block (&body, tmp);
3251     }
3252
3253   /* If this is the main program and an -fconvert option was provided,
3254      add a call to set_convert.  */
3255
3256   if (sym->attr.is_main_program && gfc_option.convert != CONVERT_NATIVE)
3257     {
3258       tmp = build_call_expr (gfor_fndecl_set_convert, 1,
3259                              build_int_cst (integer_type_node,
3260                                             gfc_option.convert));
3261       gfc_add_expr_to_block (&body, tmp);
3262     }
3263
3264   /* If this is the main program and an -frecord-marker option was provided,
3265      add a call to set_record_marker.  */
3266
3267   if (sym->attr.is_main_program && gfc_option.record_marker != 0)
3268     {
3269       tmp = build_call_expr (gfor_fndecl_set_record_marker, 1,
3270                              build_int_cst (integer_type_node,
3271                                             gfc_option.record_marker));
3272       gfc_add_expr_to_block (&body, tmp);
3273     }
3274
3275   if (sym->attr.is_main_program && gfc_option.max_subrecord_length != 0)
3276     {
3277       tmp = build_call_expr (gfor_fndecl_set_max_subrecord_length,
3278                              1,
3279                              build_int_cst (integer_type_node,
3280                                             gfc_option.max_subrecord_length));
3281       gfc_add_expr_to_block (&body, tmp);
3282     }
3283
3284   if (TREE_TYPE (DECL_RESULT (fndecl)) != void_type_node
3285       && sym->attr.subroutine)
3286     {
3287       tree alternate_return;
3288       alternate_return = gfc_get_fake_result_decl (sym, 0);
3289       gfc_add_modify_expr (&body, alternate_return, integer_zero_node);
3290     }
3291
3292   if (ns->entries)
3293     {
3294       /* Jump to the correct entry point.  */
3295       tmp = gfc_trans_entry_master_switch (ns->entries);
3296       gfc_add_expr_to_block (&body, tmp);
3297     }
3298
3299   tmp = gfc_trans_code (ns->code);
3300   gfc_add_expr_to_block (&body, tmp);
3301
3302   /* Add a return label if needed.  */
3303   if (current_function_return_label)
3304     {
3305       tmp = build1_v (LABEL_EXPR, current_function_return_label);
3306       gfc_add_expr_to_block (&body, tmp);
3307     }
3308
3309   tmp = gfc_finish_block (&body);
3310   /* Add code to create and cleanup arrays.  */
3311   tmp = gfc_trans_deferred_vars (sym, tmp);
3312
3313   if (TREE_TYPE (DECL_RESULT (fndecl)) != void_type_node)
3314     {
3315       if (sym->attr.subroutine || sym == sym->result)
3316         {
3317           if (current_fake_result_decl != NULL)
3318             result = TREE_VALUE (current_fake_result_decl);
3319           else
3320             result = NULL_TREE;
3321           current_fake_result_decl = NULL_TREE;
3322         }
3323       else
3324         result = sym->result->backend_decl;
3325
3326       if (result != NULL_TREE && sym->attr.function
3327             && sym->ts.type == BT_DERIVED
3328             && sym->ts.derived->attr.alloc_comp
3329             && !sym->attr.pointer)
3330         {
3331           rank = sym->as ? sym->as->rank : 0;
3332           tmp2 = gfc_nullify_alloc_comp (sym->ts.derived, result, rank);
3333           gfc_add_expr_to_block (&block, tmp2);
3334         }
3335
3336      gfc_add_expr_to_block (&block, tmp);
3337
3338      if (result == NULL_TREE)
3339         warning (0, "Function return value not set");
3340       else
3341         {
3342           /* Set the return value to the dummy result variable.  The
3343              types may be different for scalar default REAL functions
3344              with -ff2c, therefore we have to convert.  */
3345           tmp = convert (TREE_TYPE (DECL_RESULT (fndecl)), result);
3346           tmp = build2 (MODIFY_EXPR, TREE_TYPE (tmp),
3347                         DECL_RESULT (fndecl), tmp);
3348           tmp = build1_v (RETURN_EXPR, tmp);
3349           gfc_add_expr_to_block (&block, tmp);
3350         }
3351     }
3352   else
3353     gfc_add_expr_to_block (&block, tmp);
3354
3355
3356   /* Add all the decls we created during processing.  */
3357   decl = saved_function_decls;
3358   while (decl)
3359     {
3360       tree next;
3361
3362       next = TREE_CHAIN (decl);
3363       TREE_CHAIN (decl) = NULL_TREE;
3364       pushdecl (decl);
3365       decl = next;
3366     }
3367   saved_function_decls = NULL_TREE;
3368
3369   DECL_SAVED_TREE (fndecl) = gfc_finish_block (&block);
3370
3371   /* Finish off this function and send it for code generation.  */
3372   poplevel (1, 0, 1);
3373   BLOCK_SUPERCONTEXT (DECL_INITIAL (fndecl)) = fndecl;
3374
3375   /* Output the GENERIC tree.  */
3376   dump_function (TDI_original, fndecl);
3377
3378   /* Store the end of the function, so that we get good line number
3379      info for the epilogue.  */
3380   cfun->function_end_locus = input_location;
3381
3382   /* We're leaving the context of this function, so zap cfun.
3383      It's still in DECL_STRUCT_FUNCTION, and we'll restore it in
3384      tree_rest_of_compilation.  */
3385   cfun = NULL;
3386
3387   if (old_context)
3388     {
3389       pop_function_context ();
3390       saved_function_decls = saved_parent_function_decls;
3391     }
3392   current_function_decl = old_context;
3393
3394   if (decl_function_context (fndecl))
3395     /* Register this function with cgraph just far enough to get it
3396        added to our parent's nested function list.  */
3397     (void) cgraph_node (fndecl);
3398   else
3399     {
3400       gfc_gimplify_function (fndecl);
3401       cgraph_finalize_function (fndecl, false);
3402     }
3403 }
3404
3405 void
3406 gfc_generate_constructors (void)
3407 {
3408   gcc_assert (gfc_static_ctors == NULL_TREE);
3409 #if 0
3410   tree fnname;
3411   tree type;
3412   tree fndecl;
3413   tree decl;
3414   tree tmp;
3415
3416   if (gfc_static_ctors == NULL_TREE)
3417     return;
3418
3419   fnname = get_file_function_name ("I");
3420   type = build_function_type (void_type_node,
3421                               gfc_chainon_list (NULL_TREE, void_type_node));
3422
3423   fndecl = build_decl (FUNCTION_DECL, fnname, type);
3424   TREE_PUBLIC (fndecl) = 1;
3425
3426   decl = build_decl (RESULT_DECL, NULL_TREE, void_type_node);
3427   DECL_ARTIFICIAL (decl) = 1;
3428   DECL_IGNORED_P (decl) = 1;
3429   DECL_CONTEXT (decl) = fndecl;
3430   DECL_RESULT (fndecl) = decl;
3431
3432   pushdecl (fndecl);
3433
3434   current_function_decl = fndecl;
3435
3436   rest_of_decl_compilation (fndecl, 1, 0);
3437
3438   make_decl_rtl (fndecl);
3439
3440   init_function_start (fndecl);
3441
3442   pushlevel (0);
3443
3444   for (; gfc_static_ctors; gfc_static_ctors = TREE_CHAIN (gfc_static_ctors))
3445     {
3446       tmp = build_call_expr (TREE_VALUE (gfc_static_ctors), 0);
3447       DECL_SAVED_TREE (fndecl) = build_stmt (EXPR_STMT, tmp);
3448     }
3449
3450   poplevel (1, 0, 1);
3451
3452   BLOCK_SUPERCONTEXT (DECL_INITIAL (fndecl)) = fndecl;
3453
3454   free_after_parsing (cfun);
3455   free_after_compilation (cfun);
3456
3457   tree_rest_of_compilation (fndecl);
3458
3459   current_function_decl = NULL_TREE;
3460 #endif
3461 }
3462
3463 /* Translates a BLOCK DATA program unit. This means emitting the
3464    commons contained therein plus their initializations. We also emit
3465    a globally visible symbol to make sure that each BLOCK DATA program
3466    unit remains unique.  */
3467
3468 void
3469 gfc_generate_block_data (gfc_namespace * ns)
3470 {
3471   tree decl;
3472   tree id;
3473
3474   /* Tell the backend the source location of the block data.  */
3475   if (ns->proc_name)
3476     gfc_set_backend_locus (&ns->proc_name->declared_at);
3477   else
3478     gfc_set_backend_locus (&gfc_current_locus);
3479
3480   /* Process the DATA statements.  */
3481   gfc_trans_common (ns);
3482
3483   /* Create a global symbol with the mane of the block data.  This is to
3484      generate linker errors if the same name is used twice.  It is never
3485      really used.  */
3486   if (ns->proc_name)
3487     id = gfc_sym_mangled_function_id (ns->proc_name);
3488   else
3489     id = get_identifier ("__BLOCK_DATA__");
3490
3491   decl = build_decl (VAR_DECL, id, gfc_array_index_type);
3492   TREE_PUBLIC (decl) = 1;
3493   TREE_STATIC (decl) = 1;
3494
3495   pushdecl (decl);
3496   rest_of_decl_compilation (decl, 1, 0);
3497 }
3498
3499
3500 #include "gt-fortran-trans-decl.h"