gcc/c-pragma.c

   1 /* Handle #pragma, system V.4 style.  Supports #pragma weak and #pragma pack.
   2    Copyright (C) 1992, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004
   3    Free Software Foundation, Inc.
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify it under
   8 the terms of the GNU General Public License as published by the Free
   9 Software Foundation; either version 2, or (at your option) any later
  10 version.
  11
  12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15 for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING.  If not, write to the Free
  19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
  20 02111-1307, USA.  */
  21
  22 #include "config.h"
  23 #include "system.h"
  24 #include "coretypes.h"
  25 #include "tm.h"
  26 #include "rtl.h"
  27 #include "tree.h"
  28 #include "function.h"
  29 #include "cpplib.h"
  30 #include "c-pragma.h"
  31 #include "flags.h"
  32 #include "toplev.h"
  33 #include "ggc.h"
  34 #include "c-common.h"
  35 #include "output.h"
  36 #include "tm_p.h"
  37 #include "target.h"
  38
  39 #define GCC_BAD(msgid) do { warning (msgid); return; } while (0)
  40 #define GCC_BAD2(msgid, arg) do { warning (msgid, arg); return; } while (0)
  41
  42 typedef struct align_stack GTY(())
  43 {
  44   int                  alignment;
  45   tree                 id;
  46   struct align_stack * prev;
  47 } align_stack;
  48
  49 static GTY(()) struct align_stack * alignment_stack;
  50
  51 #ifdef HANDLE_PRAGMA_PACK
  52 static void handle_pragma_pack (cpp_reader *);
  53
  54 #ifdef HANDLE_PRAGMA_PACK_PUSH_POP
  55 /* If we have a "global" #pragma pack(<n>) in effect when the first
  56    #pragma pack(push,<n>) is encountered, this stores the value of
  57    maximum_field_alignment in effect.  When the final pop_alignment()
  58    happens, we restore the value to this, not to a value of 0 for
  59    maximum_field_alignment.  Value is in bits.  */
  60 static int default_alignment;
  61 #define SET_GLOBAL_ALIGNMENT(ALIGN) (maximum_field_alignment = *(alignment_stack == NULL \
  62         ? &default_alignment \
  63         : &alignment_stack->alignment) = (ALIGN))
  64
  65 static void push_alignment (int, tree);
  66 static void pop_alignment (tree);
  67
  68 /* Push an alignment value onto the stack.  */
  69 static void
  70 push_alignment (int alignment, tree id)
  71 {
  72   align_stack * entry;
  73
  74   entry = ggc_alloc (sizeof (* entry));
  75
  76   entry->alignment  = alignment;
  77   entry->id         = id;
  78   entry->prev       = alignment_stack;
  79
  80   /* The current value of maximum_field_alignment is not necessarily
  81      0 since there may be a #pragma pack(<n>) in effect; remember it
  82      so that we can restore it after the final #pragma pop().  */
  83   if (alignment_stack == NULL)
  84     default_alignment = maximum_field_alignment;
  85
  86   alignment_stack = entry;
  87
  88   maximum_field_alignment = alignment;
  89 }
  90
  91 /* Undo a push of an alignment onto the stack.  */
  92 static void
  93 pop_alignment (tree id)
  94 {
  95   align_stack * entry;
  96
  97   if (alignment_stack == NULL)
  98     GCC_BAD ("#pragma pack (pop) encountered without matching #pragma pack (push)");
  99
 100   /* If we got an identifier, strip away everything above the target
 101      entry so that the next step will restore the state just below it.  */
 102   if (id)
 103     {
 104       for (entry = alignment_stack; entry; entry = entry->prev)
 105         if (entry->id == id)
 106           {
 107             alignment_stack = entry;
 108             break;
 109           }
 110       if (entry == NULL)
 111         warning ("\
 112 #pragma pack(pop, %s) encountered without matching #pragma pack(push, %s)"
 113                  , IDENTIFIER_POINTER (id), IDENTIFIER_POINTER (id));
 114     }
 115
 116   entry = alignment_stack->prev;
 117
 118   maximum_field_alignment = entry ? entry->alignment : default_alignment;
 119
 120   alignment_stack = entry;
 121 }
 122 #else  /* not HANDLE_PRAGMA_PACK_PUSH_POP */
 123 #define SET_GLOBAL_ALIGNMENT(ALIGN) (maximum_field_alignment = (ALIGN))
 124 #define push_alignment(ID, N) \
 125     GCC_BAD ("#pragma pack(push[, id], <n>) is not supported on this target")
 126 #define pop_alignment(ID) \
 127     GCC_BAD ("#pragma pack(pop[, id], <n>) is not supported on this target")
 128 #endif /* HANDLE_PRAGMA_PACK_PUSH_POP */
 129
 130 /* #pragma pack ()
 131    #pragma pack (N)
 132
 133    #pragma pack (push)
 134    #pragma pack (push, N)
 135    #pragma pack (push, ID)
 136    #pragma pack (push, ID, N)
 137    #pragma pack (pop)
 138    #pragma pack (pop, ID) */
 139 static void
 140 handle_pragma_pack (cpp_reader * ARG_UNUSED (dummy))
 141 {
 142   tree x, id = 0;
 143   int align = -1;
 144   enum cpp_ttype token;
 145   enum { set, push, pop } action;
 146
 147   if (c_lex (&x) != CPP_OPEN_PAREN)
 148     GCC_BAD ("missing %<(%> after %<#pragma pack%> - ignored");
 149
 150   token = c_lex (&x);
 151   if (token == CPP_CLOSE_PAREN)
 152     {
 153       action = set;
 154       align = initial_max_fld_align;
 155     }
 156   else if (token == CPP_NUMBER)
 157     {
 158       align = TREE_INT_CST_LOW (x);
 159       action = set;
 160       if (c_lex (&x) != CPP_CLOSE_PAREN)
 161         GCC_BAD ("malformed %<#pragma pack%> - ignored");
 162     }
 163   else if (token == CPP_NAME)
 164     {
 165 #define GCC_BAD_ACTION do { if (action != pop) \
 166           GCC_BAD ("malformed %<#pragma pack(push[, id][, <n>])%> - ignored"); \
 167         else \
 168           GCC_BAD ("malformed %<#pragma pack(pop[, id])%> - ignored"); \
 169         } while (0)
 170
 171       const char *op = IDENTIFIER_POINTER (x);
 172       if (!strcmp (op, "push"))
 173         action = push;
 174       else if (!strcmp (op, "pop"))
 175         action = pop;
 176       else
 177         GCC_BAD2 ("unknown action %qs for %<#pragma pack%> - ignored", op);
 178
 179       while ((token = c_lex (&x)) == CPP_COMMA)
 180         {
 181           token = c_lex (&x);
 182           if (token == CPP_NAME && id == 0)
 183             {
 184               id = x;
 185             }
 186           else if (token == CPP_NUMBER && action == push && align == -1)
 187             {
 188               align = TREE_INT_CST_LOW (x);
 189               if (align == -1)
 190                 action = set;
 191             }
 192           else
 193             GCC_BAD_ACTION;
 194         }
 195
 196       if (token != CPP_CLOSE_PAREN)
 197         GCC_BAD_ACTION;
 198 #undef GCC_BAD_ACTION
 199     }
 200   else
 201     GCC_BAD ("malformed %<#pragma pack%> - ignored");
 202
 203   if (c_lex (&x) != CPP_EOF)
 204     warning ("junk at end of %<#pragma pack%>");
 205
 206   if (flag_pack_struct)
 207     GCC_BAD ("#pragma pack has no effect with -fpack-struct - ignored");
 208
 209   if (action != pop)
 210     switch (align)
 211       {
 212       case 0:
 213       case 1:
 214       case 2:
 215       case 4:
 216       case 8:
 217       case 16:
 218         align *= BITS_PER_UNIT;
 219         break;
 220       case -1:
 221         if (action == push)
 222           {
 223             align = maximum_field_alignment;
 224             break;
 225           }
 226       default:
 227         GCC_BAD2 ("alignment must be a small power of two, not %d", align);
 228       }
 229
 230   switch (action)
 231     {
 232     case set:   SET_GLOBAL_ALIGNMENT (align);  break;
 233     case push:  push_alignment (align, id);    break;
 234     case pop:   pop_alignment (id);            break;
 235     }
 236 }
 237 #endif  /* HANDLE_PRAGMA_PACK */
 238
 239 static GTY(()) tree pending_weaks;
 240
 241 #ifdef HANDLE_PRAGMA_WEAK
 242 static void apply_pragma_weak (tree, tree);
 243 static void handle_pragma_weak (cpp_reader *);
 244
 245 static void
 246 apply_pragma_weak (tree decl, tree value)
 247 {
 248   if (value)
 249     {
 250       value = build_string (IDENTIFIER_LENGTH (value),
 251                             IDENTIFIER_POINTER (value));
 252       decl_attributes (&decl, build_tree_list (get_identifier ("alias"),
 253                                                build_tree_list (NULL, value)),
 254                        0);
 255     }
 256
 257   if (SUPPORTS_WEAK && DECL_EXTERNAL (decl) && TREE_USED (decl)
 258       && !DECL_WEAK (decl) /* Don't complain about a redundant #pragma.  */
 259       && TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl)))
 260     warning ("%Japplying #pragma weak %qD after first use results "
 261              "in unspecified behavior", decl, decl);
 262
 263   declare_weak (decl);
 264 }
 265
 266 void
 267 maybe_apply_pragma_weak (tree decl)
 268 {
 269   tree *p, t, id;
 270
 271   /* Avoid asking for DECL_ASSEMBLER_NAME when it's not needed.  */
 272
 273   /* No weak symbols pending, take the short-cut.  */
 274   if (!pending_weaks)
 275     return;
 276   /* If it's not visible outside this file, it doesn't matter whether
 277      it's weak.  */
 278   if (!DECL_EXTERNAL (decl) && !TREE_PUBLIC (decl))
 279     return;
 280   /* If it's not a function or a variable, it can't be weak.
 281      FIXME: what kinds of things are visible outside this file but
 282      aren't functions or variables?   Should this be an assert instead?  */
 283   if (TREE_CODE (decl) != FUNCTION_DECL && TREE_CODE (decl) != VAR_DECL)
 284     return;
 285
 286   id = DECL_ASSEMBLER_NAME (decl);
 287
 288   for (p = &pending_weaks; (t = *p) ; p = &TREE_CHAIN (t))
 289     if (id == TREE_PURPOSE (t))
 290       {
 291         apply_pragma_weak (decl, TREE_VALUE (t));
 292         *p = TREE_CHAIN (t);
 293         break;
 294       }
 295 }
 296
 297 /* #pragma weak name [= value] */
 298 static void
 299 handle_pragma_weak (cpp_reader * ARG_UNUSED (dummy))
 300 {
 301   tree name, value, x, decl;
 302   enum cpp_ttype t;
 303
 304   value = 0;
 305
 306   if (c_lex (&name) != CPP_NAME)
 307     GCC_BAD ("malformed #pragma weak, ignored");
 308   t = c_lex (&x);
 309   if (t == CPP_EQ)
 310     {
 311       if (c_lex (&value) != CPP_NAME)
 312         GCC_BAD ("malformed #pragma weak, ignored");
 313       t = c_lex (&x);
 314     }
 315   if (t != CPP_EOF)
 316     warning ("junk at end of #pragma weak");
 317
 318   decl = identifier_global_value (name);
 319   if (decl && DECL_P (decl))
 320     {
 321       apply_pragma_weak (decl, value);
 322       if (value)
 323         assemble_alias (decl, value);
 324     }
 325   else
 326     pending_weaks = tree_cons (name, value, pending_weaks);
 327 }
 328 #else
 329 void
 330 maybe_apply_pragma_weak (tree ARG_UNUSED (decl))
 331 {
 332 }
 333 #endif /* HANDLE_PRAGMA_WEAK */
 334
 335 /* GCC supports two #pragma directives for renaming the external
 336    symbol associated with a declaration (DECL_ASSEMBLER_NAME), for
 337    compatibility with the Solaris and Tru64 system headers.  GCC also
 338    has its own notation for this, __asm__("name") annotations.
 339
 340    Corner cases of these features and their interaction:
 341
 342    1) Both pragmas silently apply only to declarations with external
 343       linkage (that is, TREE_PUBLIC || DECL_EXTERNAL).  Asm labels
 344       do not have this restriction.
 345
 346    2) In C++, both #pragmas silently apply only to extern "C" declarations.
 347       Asm labels do not have this restriction.
 348
 349    3) If any of the three ways of changing DECL_ASSEMBLER_NAME is
 350       applied to a decl whose DECL_ASSEMBLER_NAME is already set, and the
 351       new name is different, a warning issues and the name does not change.
 352
 353    4) The "source name" for #pragma redefine_extname is the DECL_NAME,
 354       *not* the DECL_ASSEMBLER_NAME.
 355
 356    5) If #pragma extern_prefix is in effect and a declaration occurs
 357       with an __asm__ name, the #pragma extern_prefix is silently
 358       ignored for that declaration.
 359
 360    6) If #pragma extern_prefix and #pragma redefine_extname apply to
 361       the same declaration, whichever triggered first wins, and a warning
 362       is issued.  (We would like to have #pragma redefine_extname always
 363       win, but it can appear either before or after the declaration, and
 364       if it appears afterward, we have no way of knowing whether a modified
 365       DECL_ASSEMBLER_NAME is due to #pragma extern_prefix.)  */
 366
 367 static GTY(()) tree pending_redefine_extname;
 368
 369 static void handle_pragma_redefine_extname (cpp_reader *);
 370
 371 /* #pragma redefine_extname oldname newname */
 372 static void
 373 handle_pragma_redefine_extname (cpp_reader * ARG_UNUSED (dummy))
 374 {
 375   tree oldname, newname, decl, x;
 376   enum cpp_ttype t;
 377
 378   if (c_lex (&oldname) != CPP_NAME)
 379     GCC_BAD ("malformed #pragma redefine_extname, ignored");
 380   if (c_lex (&newname) != CPP_NAME)
 381     GCC_BAD ("malformed #pragma redefine_extname, ignored");
 382   t = c_lex (&x);
 383   if (t != CPP_EOF)
 384     warning ("junk at end of #pragma redefine_extname");
 385
 386   if (!flag_mudflap && !targetm.handle_pragma_redefine_extname)
 387     {
 388       if (warn_unknown_pragmas > in_system_header)
 389         warning ("#pragma redefine_extname not supported on this target");
 390       return;
 391     }
 392
 393   decl = identifier_global_value (oldname);
 394   if (decl
 395       && (TREE_PUBLIC (decl) || DECL_EXTERNAL (decl))
 396       && (TREE_CODE (decl) == FUNCTION_DECL
 397           || TREE_CODE (decl) == VAR_DECL)
 398       && has_c_linkage (decl))
 399     {
 400       if (DECL_ASSEMBLER_NAME_SET_P (decl))
 401         {
 402           const char *name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
 403           name = targetm.strip_name_encoding (name);
 404
 405           if (strcmp (name, IDENTIFIER_POINTER (newname)))
 406             warning ("#pragma redefine_extname ignored due to conflict with "
 407                      "previous rename");
 408         }
 409       else
 410         change_decl_assembler_name (decl, newname);
 411     }
 412   else
 413     /* We have to add this to the rename list even if there's already
 414        a global value that doesn't meet the above criteria, because in
 415        C++ "struct foo {...};" puts "foo" in the current namespace but
 416        does *not* conflict with a subsequent declaration of a function
 417        or variable foo.  See g++.dg/other/pragma-re-2.C.  */
 418     add_to_renaming_pragma_list (oldname, newname);
 419 }
 420
 421 /* This is called from here and from ia64.c.  */
 422 void
 423 add_to_renaming_pragma_list (tree oldname, tree newname)
 424 {
 425   tree previous = purpose_member (oldname, pending_redefine_extname);
 426   if (previous)
 427     {
 428       if (TREE_VALUE (previous) != newname)
 429         warning ("#pragma redefine_extname ignored due to conflict with "
 430                  "previous #pragma redefine_extname");
 431       return;
 432     }
 433
 434   pending_redefine_extname
 435     = tree_cons (oldname, newname, pending_redefine_extname);
 436 }
 437
 438 static GTY(()) tree pragma_extern_prefix;
 439
 440 /* #pragma extern_prefix "prefix" */
 441 static void
 442 handle_pragma_extern_prefix (cpp_reader * ARG_UNUSED (dummy))
 443 {
 444   tree prefix, x;
 445   enum cpp_ttype t;
 446
 447   if (c_lex (&prefix) != CPP_STRING)
 448     GCC_BAD ("malformed #pragma extern_prefix, ignored");
 449   t = c_lex (&x);
 450   if (t != CPP_EOF)
 451     warning ("junk at end of #pragma extern_prefix");
 452
 453   if (targetm.handle_pragma_extern_prefix)
 454     /* Note that the length includes the null terminator.  */
 455     pragma_extern_prefix = (TREE_STRING_LENGTH (prefix) > 1 ? prefix : NULL);
 456   else if (warn_unknown_pragmas > in_system_header)
 457     warning ("#pragma extern_prefix not supported on this target");
 458 }
 459
 460 /* Hook from the front ends to apply the results of one of the preceding
 461    pragmas that rename variables.  */
 462
 463 tree
 464 maybe_apply_renaming_pragma (tree decl, tree asmname)
 465 {
 466   tree *p, t;
 467
 468   /* The renaming pragmas are only applied to declarations with
 469      external linkage.  */
 470   if ((TREE_CODE (decl) != FUNCTION_DECL && TREE_CODE (decl) != VAR_DECL)
 471       || (!TREE_PUBLIC (decl) && !DECL_EXTERNAL (decl))
 472       || !has_c_linkage (decl))
 473     return asmname;
 474
 475   /* If the DECL_ASSEMBLER_NAME is already set, it does not change,
 476      but we may warn about a rename that conflicts.  */
 477   if (DECL_ASSEMBLER_NAME_SET_P (decl))
 478     {
 479       const char *oldname = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
 480       oldname = targetm.strip_name_encoding (oldname);
 481
 482       if (asmname && strcmp (TREE_STRING_POINTER (asmname), oldname))
 483           warning ("asm declaration ignored due to "
 484                    "conflict with previous rename");
 485
 486       /* Take any pending redefine_extname off the list.  */
 487       for (p = &pending_redefine_extname; (t = *p); p = &TREE_CHAIN (t))
 488         if (DECL_NAME (decl) == TREE_PURPOSE (t))
 489           {
 490             /* Only warn if there is a conflict.  */
 491             if (strcmp (IDENTIFIER_POINTER (TREE_VALUE (t)), oldname))
 492               warning ("#pragma redefine_extname ignored due to "
 493                        "conflict with previous rename");
 494
 495             *p = TREE_CHAIN (t);
 496             break;
 497           }
 498       return 0;
 499     }
 500
 501   /* Find out if we have a pending #pragma redefine_extname.  */
 502   for (p = &pending_redefine_extname; (t = *p); p = &TREE_CHAIN (t))
 503     if (DECL_NAME (decl) == TREE_PURPOSE (t))
 504       {
 505         tree newname = TREE_VALUE (t);
 506         *p = TREE_CHAIN (t);
 507
 508         /* If we already have an asmname, #pragma redefine_extname is
 509            ignored (with a warning if it conflicts).  */
 510         if (asmname)
 511           {
 512             if (strcmp (TREE_STRING_POINTER (asmname),
 513                         IDENTIFIER_POINTER (newname)) != 0)
 514               warning ("#pragma redefine_extname ignored due to "
 515                        "conflict with __asm__ declaration");
 516             return asmname;
 517           }
 518
 519         /* Otherwise we use what we've got; #pragma extern_prefix is
 520            silently ignored.  */
 521         return build_string (IDENTIFIER_LENGTH (newname),
 522                              IDENTIFIER_POINTER (newname));
 523       }
 524
 525   /* If we've got an asmname, #pragma extern_prefix is silently ignored.  */
 526   if (asmname)
 527     return asmname;
 528
 529   /* If #pragma extern_prefix is in effect, apply it.  */
 530   if (pragma_extern_prefix)
 531     {
 532       const char *prefix = TREE_STRING_POINTER (pragma_extern_prefix);
 533       size_t plen = TREE_STRING_LENGTH (pragma_extern_prefix) - 1;
 534
 535       const char *id = IDENTIFIER_POINTER (DECL_NAME (decl));
 536       size_t ilen = IDENTIFIER_LENGTH (DECL_NAME (decl));
 537
 538       char *newname = (char *) alloca (plen + ilen + 1);
 539
 540       memcpy (newname,        prefix, plen);
 541       memcpy (newname + plen, id, ilen + 1);
 542
 543       return build_string (plen + ilen, newname);
 544     }
 545
 546   /* Nada.  */
 547   return 0;
 548 }
 549
 550
 551 #ifdef HANDLE_PRAGMA_VISIBILITY
 552 static void handle_pragma_visibility (cpp_reader *);
 553
 554 /* Sets the default visibility for symbols to something other than that
 555    specified on the command line.  */
 556 static void
 557 handle_pragma_visibility (cpp_reader *dummy ATTRIBUTE_UNUSED)
 558 { /* Form is #pragma GCC visibility push(hidden)|pop */
 559   static int visstack [16], visidx;
 560   tree x;
 561   enum cpp_ttype token;
 562   enum { bad, push, pop } action = bad;
 563
 564   token = c_lex (&x);
 565   if (token == CPP_NAME)
 566     {
 567       const char *op = IDENTIFIER_POINTER (x);
 568       if (!strcmp (op, "push"))
 569         action = push;
 570       else if (!strcmp (op, "pop"))
 571         action = pop;
 572     }
 573   if (bad == action)
 574     GCC_BAD ("#pragma GCC visibility must be followed by push or pop");
 575   else
 576     {
 577       if (pop == action)
 578         {
 579           if (!visidx)
 580             {
 581               GCC_BAD ("No matching push for %<#pragma GCC visibility pop%>");
 582             }
 583           else
 584             {
 585               default_visibility = visstack[--visidx];
 586               visibility_options.inpragma = (visidx>0);
 587             }
 588         }
 589       else
 590         {
 591           if (c_lex (&x) != CPP_OPEN_PAREN)
 592             GCC_BAD ("missing %<(%> after %<#pragma GCC visibility push%> - ignored");
 593           token = c_lex (&x);
 594           if (token != CPP_NAME)
 595             {
 596               GCC_BAD ("malformed #pragma GCC visibility push");
 597             }
 598           else if (visidx >= 16)
 599             {
 600               GCC_BAD ("No more than sixteen #pragma GCC visibility pushes allowed at once");
 601             }
 602           else
 603             {
 604               const char *str = IDENTIFIER_POINTER (x);
 605               visstack[visidx++] = default_visibility;
 606               if (!strcmp (str, "default"))
 607                 default_visibility = VISIBILITY_DEFAULT;
 608               else if (!strcmp (str, "internal"))
 609                 default_visibility = VISIBILITY_INTERNAL;
 610               else if (!strcmp (str, "hidden"))
 611                 default_visibility = VISIBILITY_HIDDEN;
 612               else if (!strcmp (str, "protected"))
 613                 default_visibility = VISIBILITY_PROTECTED;
 614               else
 615                 {
 616                   GCC_BAD ("#pragma GCC visibility push() must specify default, internal, hidden or protected");
 617                 }
 618               visibility_options.inpragma = 1;
 619             }
 620           if (c_lex (&x) != CPP_CLOSE_PAREN)
 621             GCC_BAD ("missing '(' after %<#pragma GCC visibility push%> - ignored");
 622         }
 623     }
 624   if (c_lex (&x) != CPP_EOF)
 625     warning ("junk at end of %<#pragma GCC visibility%>");
 626 }
 627
 628 #endif
 629
 630 /* Front-end wrapper for pragma registration to avoid dragging
 631    cpplib.h in almost everywhere.  */
 632 void
 633 c_register_pragma (const char *space, const char *name,
 634                    void (*handler) (struct cpp_reader *))
 635 {
 636   cpp_register_pragma (parse_in, space, name, handler);
 637 }
 638
 639 /* Set up front-end pragmas.  */
 640 void
 641 init_pragma (void)
 642 {
 643 #ifdef HANDLE_PRAGMA_PACK
 644   c_register_pragma (0, "pack", handle_pragma_pack);
 645 #endif
 646 #ifdef HANDLE_PRAGMA_WEAK
 647   c_register_pragma (0, "weak", handle_pragma_weak);
 648 #endif
 649 #ifdef HANDLE_PRAGMA_VISIBILITY
 650   c_register_pragma ("GCC", "visibility", handle_pragma_visibility);
 651 #endif
 652
 653   c_register_pragma (0, "redefine_extname", handle_pragma_redefine_extname);
 654   c_register_pragma (0, "extern_prefix", handle_pragma_extern_prefix);
 655
 656   c_register_pragma ("GCC", "pch_preprocess", c_common_pch_pragma);
 657
 658 #ifdef REGISTER_TARGET_PRAGMAS
 659   REGISTER_TARGET_PRAGMAS ();
 660 #endif
 661 }
 662
 663 #include "gt-c-pragma.h"