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 /* Process all "#pragma weak A = B" directives where we have not seen
 298    a decl for A.  */
 299 void
 300 maybe_apply_pending_pragma_weaks (void)
 301 {
 302   tree *p, t, alias_id, id, decl, *next;
 303
 304   for (p = &pending_weaks; (t = *p) ; p = next)
 305     {
 306       next = &TREE_CHAIN (t);
 307       alias_id = TREE_PURPOSE (t);
 308       id = TREE_VALUE (t);
 309
 310       if (TREE_VALUE (t) == NULL)
 311         continue;
 312
 313       decl = build_decl (FUNCTION_DECL, alias_id, default_function_type);
 314
 315       DECL_ARTIFICIAL (decl) = 1;
 316       TREE_PUBLIC (decl) = 1;
 317       DECL_EXTERNAL (decl) = 1;
 318       DECL_WEAK (decl) = 1;
 319
 320       assemble_alias (decl, id);
 321     }
 322 }
 323
 324 /* #pragma weak name [= value] */
 325 static void
 326 handle_pragma_weak (cpp_reader * ARG_UNUSED (dummy))
 327 {
 328   tree name, value, x, decl;
 329   enum cpp_ttype t;
 330
 331   value = 0;
 332
 333   if (c_lex (&name) != CPP_NAME)
 334     GCC_BAD ("malformed #pragma weak, ignored");
 335   t = c_lex (&x);
 336   if (t == CPP_EQ)
 337     {
 338       if (c_lex (&value) != CPP_NAME)
 339         GCC_BAD ("malformed #pragma weak, ignored");
 340       t = c_lex (&x);
 341     }
 342   if (t != CPP_EOF)
 343     warning ("junk at end of #pragma weak");
 344
 345   decl = identifier_global_value (name);
 346   if (decl && DECL_P (decl))
 347     {
 348       apply_pragma_weak (decl, value);
 349       if (value)
 350         assemble_alias (decl, value);
 351     }
 352   else
 353     pending_weaks = tree_cons (name, value, pending_weaks);
 354 }
 355 #else
 356 void
 357 maybe_apply_pragma_weak (tree ARG_UNUSED (decl))
 358 {
 359 }
 360
 361 void
 362 maybe_apply_pending_pragma_weaks (void)
 363 {
 364 }
 365 #endif /* HANDLE_PRAGMA_WEAK */
 366
 367 /* GCC supports two #pragma directives for renaming the external
 368    symbol associated with a declaration (DECL_ASSEMBLER_NAME), for
 369    compatibility with the Solaris and Tru64 system headers.  GCC also
 370    has its own notation for this, __asm__("name") annotations.
 371
 372    Corner cases of these features and their interaction:
 373
 374    1) Both pragmas silently apply only to declarations with external
 375       linkage (that is, TREE_PUBLIC || DECL_EXTERNAL).  Asm labels
 376       do not have this restriction.
 377
 378    2) In C++, both #pragmas silently apply only to extern "C" declarations.
 379       Asm labels do not have this restriction.
 380
 381    3) If any of the three ways of changing DECL_ASSEMBLER_NAME is
 382       applied to a decl whose DECL_ASSEMBLER_NAME is already set, and the
 383       new name is different, a warning issues and the name does not change.
 384
 385    4) The "source name" for #pragma redefine_extname is the DECL_NAME,
 386       *not* the DECL_ASSEMBLER_NAME.
 387
 388    5) If #pragma extern_prefix is in effect and a declaration occurs
 389       with an __asm__ name, the #pragma extern_prefix is silently
 390       ignored for that declaration.
 391
 392    6) If #pragma extern_prefix and #pragma redefine_extname apply to
 393       the same declaration, whichever triggered first wins, and a warning
 394       is issued.  (We would like to have #pragma redefine_extname always
 395       win, but it can appear either before or after the declaration, and
 396       if it appears afterward, we have no way of knowing whether a modified
 397       DECL_ASSEMBLER_NAME is due to #pragma extern_prefix.)  */
 398
 399 static GTY(()) tree pending_redefine_extname;
 400
 401 static void handle_pragma_redefine_extname (cpp_reader *);
 402
 403 /* #pragma redefine_extname oldname newname */
 404 static void
 405 handle_pragma_redefine_extname (cpp_reader * ARG_UNUSED (dummy))
 406 {
 407   tree oldname, newname, decl, x;
 408   enum cpp_ttype t;
 409
 410   if (c_lex (&oldname) != CPP_NAME)
 411     GCC_BAD ("malformed #pragma redefine_extname, ignored");
 412   if (c_lex (&newname) != CPP_NAME)
 413     GCC_BAD ("malformed #pragma redefine_extname, ignored");
 414   t = c_lex (&x);
 415   if (t != CPP_EOF)
 416     warning ("junk at end of #pragma redefine_extname");
 417
 418   if (!flag_mudflap && !targetm.handle_pragma_redefine_extname)
 419     {
 420       if (warn_unknown_pragmas > in_system_header)
 421         warning ("#pragma redefine_extname not supported on this target");
 422       return;
 423     }
 424
 425   decl = identifier_global_value (oldname);
 426   if (decl
 427       && (TREE_PUBLIC (decl) || DECL_EXTERNAL (decl))
 428       && (TREE_CODE (decl) == FUNCTION_DECL
 429           || TREE_CODE (decl) == VAR_DECL)
 430       && has_c_linkage (decl))
 431     {
 432       if (DECL_ASSEMBLER_NAME_SET_P (decl))
 433         {
 434           const char *name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
 435           name = targetm.strip_name_encoding (name);
 436
 437           if (strcmp (name, IDENTIFIER_POINTER (newname)))
 438             warning ("#pragma redefine_extname ignored due to conflict with "
 439                      "previous rename");
 440         }
 441       else
 442         change_decl_assembler_name (decl, newname);
 443     }
 444   else
 445     /* We have to add this to the rename list even if there's already
 446        a global value that doesn't meet the above criteria, because in
 447        C++ "struct foo {...};" puts "foo" in the current namespace but
 448        does *not* conflict with a subsequent declaration of a function
 449        or variable foo.  See g++.dg/other/pragma-re-2.C.  */
 450     add_to_renaming_pragma_list (oldname, newname);
 451 }
 452
 453 /* This is called from here and from ia64.c.  */
 454 void
 455 add_to_renaming_pragma_list (tree oldname, tree newname)
 456 {
 457   tree previous = purpose_member (oldname, pending_redefine_extname);
 458   if (previous)
 459     {
 460       if (TREE_VALUE (previous) != newname)
 461         warning ("#pragma redefine_extname ignored due to conflict with "
 462                  "previous #pragma redefine_extname");
 463       return;
 464     }
 465
 466   pending_redefine_extname
 467     = tree_cons (oldname, newname, pending_redefine_extname);
 468 }
 469
 470 static GTY(()) tree pragma_extern_prefix;
 471
 472 /* #pragma extern_prefix "prefix" */
 473 static void
 474 handle_pragma_extern_prefix (cpp_reader * ARG_UNUSED (dummy))
 475 {
 476   tree prefix, x;
 477   enum cpp_ttype t;
 478
 479   if (c_lex (&prefix) != CPP_STRING)
 480     GCC_BAD ("malformed #pragma extern_prefix, ignored");
 481   t = c_lex (&x);
 482   if (t != CPP_EOF)
 483     warning ("junk at end of #pragma extern_prefix");
 484
 485   if (targetm.handle_pragma_extern_prefix)
 486     /* Note that the length includes the null terminator.  */
 487     pragma_extern_prefix = (TREE_STRING_LENGTH (prefix) > 1 ? prefix : NULL);
 488   else if (warn_unknown_pragmas > in_system_header)
 489     warning ("#pragma extern_prefix not supported on this target");
 490 }
 491
 492 /* Hook from the front ends to apply the results of one of the preceding
 493    pragmas that rename variables.  */
 494
 495 tree
 496 maybe_apply_renaming_pragma (tree decl, tree asmname)
 497 {
 498   tree *p, t;
 499
 500   /* The renaming pragmas are only applied to declarations with
 501      external linkage.  */
 502   if ((TREE_CODE (decl) != FUNCTION_DECL && TREE_CODE (decl) != VAR_DECL)
 503       || (!TREE_PUBLIC (decl) && !DECL_EXTERNAL (decl))
 504       || !has_c_linkage (decl))
 505     return asmname;
 506
 507   /* If the DECL_ASSEMBLER_NAME is already set, it does not change,
 508      but we may warn about a rename that conflicts.  */
 509   if (DECL_ASSEMBLER_NAME_SET_P (decl))
 510     {
 511       const char *oldname = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
 512       oldname = targetm.strip_name_encoding (oldname);
 513
 514       if (asmname && strcmp (TREE_STRING_POINTER (asmname), oldname))
 515           warning ("asm declaration ignored due to "
 516                    "conflict with previous rename");
 517
 518       /* Take any pending redefine_extname off the list.  */
 519       for (p = &pending_redefine_extname; (t = *p); p = &TREE_CHAIN (t))
 520         if (DECL_NAME (decl) == TREE_PURPOSE (t))
 521           {
 522             /* Only warn if there is a conflict.  */
 523             if (strcmp (IDENTIFIER_POINTER (TREE_VALUE (t)), oldname))
 524               warning ("#pragma redefine_extname ignored due to "
 525                        "conflict with previous rename");
 526
 527             *p = TREE_CHAIN (t);
 528             break;
 529           }
 530       return 0;
 531     }
 532
 533   /* Find out if we have a pending #pragma redefine_extname.  */
 534   for (p = &pending_redefine_extname; (t = *p); p = &TREE_CHAIN (t))
 535     if (DECL_NAME (decl) == TREE_PURPOSE (t))
 536       {
 537         tree newname = TREE_VALUE (t);
 538         *p = TREE_CHAIN (t);
 539
 540         /* If we already have an asmname, #pragma redefine_extname is
 541            ignored (with a warning if it conflicts).  */
 542         if (asmname)
 543           {
 544             if (strcmp (TREE_STRING_POINTER (asmname),
 545                         IDENTIFIER_POINTER (newname)) != 0)
 546               warning ("#pragma redefine_extname ignored due to "
 547                        "conflict with __asm__ declaration");
 548             return asmname;
 549           }
 550
 551         /* Otherwise we use what we've got; #pragma extern_prefix is
 552            silently ignored.  */
 553         return build_string (IDENTIFIER_LENGTH (newname),
 554                              IDENTIFIER_POINTER (newname));
 555       }
 556
 557   /* If we've got an asmname, #pragma extern_prefix is silently ignored.  */
 558   if (asmname)
 559     return asmname;
 560
 561   /* If #pragma extern_prefix is in effect, apply it.  */
 562   if (pragma_extern_prefix)
 563     {
 564       const char *prefix = TREE_STRING_POINTER (pragma_extern_prefix);
 565       size_t plen = TREE_STRING_LENGTH (pragma_extern_prefix) - 1;
 566
 567       const char *id = IDENTIFIER_POINTER (DECL_NAME (decl));
 568       size_t ilen = IDENTIFIER_LENGTH (DECL_NAME (decl));
 569
 570       char *newname = (char *) alloca (plen + ilen + 1);
 571
 572       memcpy (newname,        prefix, plen);
 573       memcpy (newname + plen, id, ilen + 1);
 574
 575       return build_string (plen + ilen, newname);
 576     }
 577
 578   /* Nada.  */
 579   return 0;
 580 }
 581
 582
 583 #ifdef HANDLE_PRAGMA_VISIBILITY
 584 static void handle_pragma_visibility (cpp_reader *);
 585
 586 /* Sets the default visibility for symbols to something other than that
 587    specified on the command line.  */
 588 static void
 589 handle_pragma_visibility (cpp_reader *dummy ATTRIBUTE_UNUSED)
 590 { /* Form is #pragma GCC visibility push(hidden)|pop */
 591   static int visstack [16], visidx;
 592   tree x;
 593   enum cpp_ttype token;
 594   enum { bad, push, pop } action = bad;
 595
 596   token = c_lex (&x);
 597   if (token == CPP_NAME)
 598     {
 599       const char *op = IDENTIFIER_POINTER (x);
 600       if (!strcmp (op, "push"))
 601         action = push;
 602       else if (!strcmp (op, "pop"))
 603         action = pop;
 604     }
 605   if (bad == action)
 606     GCC_BAD ("#pragma GCC visibility must be followed by push or pop");
 607   else
 608     {
 609       if (pop == action)
 610         {
 611           if (!visidx)
 612             {
 613               GCC_BAD ("No matching push for %<#pragma GCC visibility pop%>");
 614             }
 615           else
 616             {
 617               default_visibility = visstack[--visidx];
 618               visibility_options.inpragma = (visidx>0);
 619             }
 620         }
 621       else
 622         {
 623           if (c_lex (&x) != CPP_OPEN_PAREN)
 624             GCC_BAD ("missing %<(%> after %<#pragma GCC visibility push%> - ignored");
 625           token = c_lex (&x);
 626           if (token != CPP_NAME)
 627             {
 628               GCC_BAD ("malformed #pragma GCC visibility push");
 629             }
 630           else if (visidx >= 16)
 631             {
 632               GCC_BAD ("No more than sixteen #pragma GCC visibility pushes allowed at once");
 633             }
 634           else
 635             {
 636               const char *str = IDENTIFIER_POINTER (x);
 637               visstack[visidx++] = default_visibility;
 638               if (!strcmp (str, "default"))
 639                 default_visibility = VISIBILITY_DEFAULT;
 640               else if (!strcmp (str, "internal"))
 641                 default_visibility = VISIBILITY_INTERNAL;
 642               else if (!strcmp (str, "hidden"))
 643                 default_visibility = VISIBILITY_HIDDEN;
 644               else if (!strcmp (str, "protected"))
 645                 default_visibility = VISIBILITY_PROTECTED;
 646               else
 647                 {
 648                   GCC_BAD ("#pragma GCC visibility push() must specify default, internal, hidden or protected");
 649                 }
 650               visibility_options.inpragma = 1;
 651             }
 652           if (c_lex (&x) != CPP_CLOSE_PAREN)
 653             GCC_BAD ("missing %<(%> after %<#pragma GCC visibility push%> - ignored");
 654         }
 655     }
 656   if (c_lex (&x) != CPP_EOF)
 657     warning ("junk at end of %<#pragma GCC visibility%>");
 658 }
 659
 660 #endif
 661
 662 /* Front-end wrappers for pragma registration to avoid dragging
 663    cpplib.h in almost everywhere.  */
 664 void
 665 c_register_pragma (const char *space, const char *name,
 666                    void (*handler) (struct cpp_reader *))
 667 {
 668   cpp_register_pragma (parse_in, space, name, handler, 0);
 669 }
 670
 671 void
 672 c_register_pragma_with_expansion (const char *space, const char *name,
 673                                   void (*handler) (struct cpp_reader *))
 674 {
 675   cpp_register_pragma (parse_in, space, name, handler, 1);
 676 }
 677
 678 /* Set up front-end pragmas.  */
 679 void
 680 init_pragma (void)
 681 {
 682 #ifdef HANDLE_PRAGMA_PACK
 683 #ifdef HANDLE_PRAGMA_PACK_WITH_EXPANSION
 684   c_register_pragma_with_expansion (0, "pack", handle_pragma_pack);
 685 #else
 686   c_register_pragma (0, "pack", handle_pragma_pack);
 687 #endif
 688 #endif
 689 #ifdef HANDLE_PRAGMA_WEAK
 690   c_register_pragma (0, "weak", handle_pragma_weak);
 691 #endif
 692 #ifdef HANDLE_PRAGMA_VISIBILITY
 693   c_register_pragma ("GCC", "visibility", handle_pragma_visibility);
 694 #endif
 695
 696   c_register_pragma (0, "redefine_extname", handle_pragma_redefine_extname);
 697   c_register_pragma (0, "extern_prefix", handle_pragma_extern_prefix);
 698
 699   c_register_pragma ("GCC", "pch_preprocess", c_common_pch_pragma);
 700
 701 #ifdef REGISTER_TARGET_PRAGMAS
 702   REGISTER_TARGET_PRAGMAS ();
 703 #endif
 704 }
 705
 706 #include "gt-c-pragma.h"