gcc/objc/objc-runtime-shared-support.c

   1 /* Support routines shared by all runtimes.
   2    Copyright (C) 2011-2020 Free Software Foundation, Inc.
   3    Contributed by Iain Sandoe (partially split from objc-act.c)
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 3, or (at your option)
  10 any later version.
  11
  12 GCC is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING3.  If not see
  19 <http://www.gnu.org/licenses/>.  */
  20
  21 #include "config.h"
  22 #include "system.h"
  23 #include "coretypes.h"
  24 #include "tm.h"
  25 #include "stringpool.h"
  26
  27 #ifdef OBJCPLUS
  28 #include "cp/cp-tree.h"
  29 #else
  30 #include "c/c-tree.h"
  31 #include "c/c-lang.h"
  32 #endif
  33 #include "c-family/c-objc.h"
  34 #include "objc-act.h"
  35
  36 /* When building Objective-C++, we are not linking against the C front-end
  37    and so need to replicate the C tree-construction functions in some way.  */
  38 #ifdef OBJCPLUS
  39 #define OBJCP_REMAP_FUNCTIONS
  40 #include "objcp-decl.h"
  41 #endif  /* OBJCPLUS */
  42
  43 /* Hooks for string decls etc.  */
  44 #include "objc-runtime-hooks.h"
  45
  46 #include "objc-runtime-shared-support.h"
  47 #include "objc-encoding.h"
  48
  49 /* rt_trees identifiers - shared between NeXT implementations.  These allow
  50    the FE to tag meta-data in a manner that survives LTO and can be used when
  51    the  runtime requires that certain meta-data items appear in particular
  52    named sections.  */
  53 #include "objc-next-metadata-tags.h"
  54 extern GTY(()) tree objc_rt_trees[OCTI_RT_META_MAX];
  55
  56 /* Rather than repeatedly looking up the identifiers, we save them here.  */
  57 tree objc_rt_trees[OCTI_RT_META_MAX];
  58
  59 /* For building an objc struct.  These might not be used when this file
  60    is compiled as part of obj-c++.  */
  61
  62 static bool objc_building_struct;
  63 static struct c_struct_parse_info *objc_struct_info ATTRIBUTE_UNUSED;
  64
  65 /* Start building a struct for objc.  */
  66
  67 tree
  68 objc_start_struct (tree name)
  69 {
  70   gcc_assert (!objc_building_struct);
  71   objc_building_struct = true;
  72   return start_struct (input_location, RECORD_TYPE, name, &objc_struct_info);
  73 }
  74
  75 /* Finish building a struct for objc.  */
  76
  77 tree
  78 objc_finish_struct (tree type, tree fieldlist)
  79 {
  80   gcc_assert (objc_building_struct);
  81   objc_building_struct = false;
  82   return finish_struct (input_location, type, fieldlist, NULL_TREE,
  83                         objc_struct_info);
  84 }
  85
  86 tree
  87 build_sized_array_type (tree base_type, int size)
  88 {
  89   tree index_type = build_index_type (build_int_cst (NULL_TREE, size - 1));
  90   return build_array_type (base_type, index_type);
  91 }
  92
  93 /* Create a declaration for field NAME of a given TYPE.  */
  94
  95 static tree
  96 create_field_decl (tree type, const char *name)
  97 {
  98   return build_decl (input_location,
  99                      FIELD_DECL, get_identifier (name), type);
 100 }
 101
 102 tree
 103 add_field_decl (tree type, const char *name, tree **chain)
 104 {
 105   tree field = create_field_decl (type, name);
 106
 107   if (*chain != NULL)
 108     **chain = field;
 109   *chain = &DECL_CHAIN (field);
 110
 111   return field;
 112 }
 113
 114 /* Create a global, static declaration for variable NAME of a given TYPE.  The
 115    finish_var_decl() routine will need to be called on it afterwards.  */
 116
 117 tree
 118 start_var_decl (tree type, const char *name)
 119 {
 120   tree var = build_decl (input_location,
 121                          VAR_DECL, get_identifier (name), type);
 122   TREE_STATIC (var) = 1;
 123   DECL_INITIAL (var) = error_mark_node;  /* A real initializer is coming... */
 124   DECL_IGNORED_P (var) = 1;
 125   DECL_ARTIFICIAL (var) = 1;
 126   DECL_CONTEXT (var) = NULL_TREE;
 127 #ifdef OBJCPLUS
 128   DECL_THIS_STATIC (var) = 1; /* squash redeclaration errors */
 129 #endif
 130   return var;
 131 }
 132
 133 /* Finish off the variable declaration created by start_var_decl().  */
 134
 135 void
 136 finish_var_decl (tree var, tree initializer)
 137 {
 138   finish_decl (var, input_location, initializer, NULL_TREE, NULL_TREE);
 139 }
 140
 141 /* Just a handy wrapper for add_objc_string.  */
 142
 143 tree
 144 build_selector (tree ident)
 145 {
 146   return convert (objc_selector_type, add_objc_string (ident, meth_var_names));
 147 }
 148
 149 /* --- templates --- */
 150
 151 /* Set 'objc_super_template' to the data type node for 'struct _objc_super'.
 152    This needs to be done just once per compilation.  */
 153
 154 /* struct _objc_super {
 155      struct _objc_object *self;
 156      struct _objc_class *super_class;
 157                 [or Class cls; for the abi v2]
 158    };  */
 159
 160 void
 161 build_super_template (void)
 162 {
 163   tree decls, *chain = NULL;
 164
 165   objc_super_template = objc_start_struct (get_identifier (UTAG_SUPER));
 166
 167   /* struct _objc_object *self; */
 168   decls = add_field_decl (objc_object_type, "self", &chain);
 169
 170   /* struct _objc_class *super_class; */
 171   add_field_decl (build_pointer_type (objc_class_template),
 172                   "super_class", &chain);
 173
 174   objc_finish_struct (objc_super_template, decls);
 175 }
 176
 177 /* To accomplish method prototyping without generating all kinds of
 178    inane warnings, the definition of the dispatch table entries were
 179    changed from:
 180
 181         struct objc_method { SEL _cmd; ...; id (*_imp)(); };
 182    to:
 183         struct objc_method { SEL _cmd; ...; void *_imp; };  */
 184
 185 tree
 186 build_method_template (void)
 187 {
 188   tree _SLT_record;
 189   tree decls, *chain = NULL;
 190
 191   _SLT_record = objc_start_struct (get_identifier (UTAG_METHOD));
 192
 193   /* SEL _cmd; */
 194   decls = add_field_decl (objc_selector_type, "_cmd", &chain);
 195
 196   /* char *method_types; */
 197   add_field_decl (string_type_node, "method_types", &chain);
 198
 199   /* void *_imp; */
 200   add_field_decl (build_pointer_type (void_type_node), "_imp", &chain);
 201
 202   objc_finish_struct (_SLT_record, decls);
 203
 204   return _SLT_record;
 205 }
 206
 207 tree
 208 build_method_prototype_template (void)
 209 {
 210   tree proto_record;
 211   tree decls, *chain = NULL;
 212
 213   proto_record = objc_start_struct (get_identifier (UTAG_METHOD_PROTOTYPE));
 214
 215   /* SEL _cmd; */
 216   decls = add_field_decl (objc_selector_type, "_cmd", &chain);
 217
 218   /* char *method_types; */
 219   add_field_decl (string_type_node, "method_types", &chain);
 220
 221   objc_finish_struct (proto_record, decls);
 222
 223   return proto_record;
 224 }
 225
 226 /* struct {
 227      struct _objc__method_prototype_list *method_next;
 228      int method_count;
 229      struct objc_method method_list[method_count];
 230    };  */
 231
 232 tree
 233 build_method_list_template (tree list_type, int size)
 234 {
 235   tree objc_ivar_list_record;
 236   tree array_type, decls, *chain = NULL;
 237
 238   objc_ivar_list_record = objc_start_struct (NULL_TREE);
 239
 240   /* struct _objc__method_prototype_list *method_next; */
 241   decls = add_field_decl (objc_method_proto_list_ptr, "method_next", &chain);
 242
 243   /* int method_count; */
 244   add_field_decl (integer_type_node, "method_count", &chain);
 245
 246   /* struct objc_method method_list[]; */
 247   array_type = build_sized_array_type (list_type, size);
 248   add_field_decl (array_type, "method_list", &chain);
 249
 250   objc_finish_struct (objc_ivar_list_record, decls);
 251
 252   return objc_ivar_list_record;
 253 }
 254
 255 /* struct objc_method_prototype_list {
 256      int count;
 257      struct objc_method_prototype {
 258         SEL name;
 259         char *types;
 260      } list[1];
 261    };  */
 262
 263 tree
 264 build_method_prototype_list_template (tree list_type, int size)
 265 {
 266   tree objc_ivar_list_record;
 267   tree array_type, decls, *chain = NULL;
 268
 269   /* Generate an unnamed struct definition.  */
 270
 271   objc_ivar_list_record = objc_start_struct (NULL_TREE);
 272
 273   /* int method_count; */
 274   decls = add_field_decl (integer_type_node, "method_count", &chain);
 275
 276   /* struct objc_method method_list[]; */
 277   array_type = build_sized_array_type (list_type, size);
 278   add_field_decl (array_type, "method_list", &chain);
 279
 280   objc_finish_struct (objc_ivar_list_record, decls);
 281
 282   return objc_ivar_list_record;
 283 }
 284
 285 /* --- names, decls entry --- */
 286
 287 /* For each string section we have a chain which maps identifier nodes
 288    to decls for the strings.  */
 289
 290 static GTY(()) int meth_var_names_idx;
 291 static GTY(()) int meth_var_types_idx;
 292 static GTY(()) int property_name_attr_idx;
 293
 294 tree
 295 add_objc_string (tree ident, string_section section)
 296 {
 297   tree *chain, decl, type;
 298   char buf[BUFSIZE];
 299
 300   switch (section)
 301     {
 302     case class_names:
 303       chain = &class_names_chain;
 304       snprintf (buf, BUFSIZE, "_OBJC_ClassName_%s", IDENTIFIER_POINTER (ident));
 305       break;
 306     case meth_var_names:
 307       chain = &meth_var_names_chain;
 308       snprintf (buf, BUFSIZE, "_OBJC_METH_VAR_NAME_%d", meth_var_names_idx++);
 309       break;
 310     case meth_var_types:
 311       chain = &meth_var_types_chain;
 312       snprintf (buf, BUFSIZE, "_OBJC_METH_VAR_TYPE_%d", meth_var_types_idx++);
 313       break;
 314     case prop_names_attr:
 315       chain = &prop_names_attr_chain;
 316       snprintf (buf, BUFSIZE, "_OBJC_PropertyAttributeOrName_%d", property_name_attr_idx++);
 317       break;
 318     default:
 319       gcc_unreachable ();
 320     }
 321
 322   while (*chain)
 323     {
 324       if (TREE_VALUE (*chain) == ident)
 325         return convert (string_type_node,
 326                         build_unary_op (input_location,
 327                                         ADDR_EXPR, TREE_PURPOSE (*chain), 1));
 328
 329       chain = &TREE_CHAIN (*chain);
 330     }
 331
 332   type = build_sized_array_type (char_type_node, IDENTIFIER_LENGTH (ident) + 1);
 333   /* Get a runtime-specific string decl which will be finish_var()'ed in
 334      generate_strings ().  */
 335   decl = (*runtime.string_decl) (type, buf, section);
 336   TREE_CONSTANT (decl) = 1;
 337   *chain = tree_cons (decl, ident, NULL_TREE);
 338
 339   return convert (string_type_node,
 340                   build_unary_op (input_location, ADDR_EXPR, decl, 1));
 341 }
 342
 343 /* --- shared metadata routines --- */
 344
 345 tree
 346 build_descriptor_table_initializer (tree type, tree entries)
 347 {
 348   vec<constructor_elt, va_gc> *inits = NULL;
 349
 350   do
 351     {
 352       vec<constructor_elt, va_gc> *elts = NULL;
 353
 354       CONSTRUCTOR_APPEND_ELT (elts, NULL_TREE,
 355                               build_selector (METHOD_SEL_NAME (entries)));
 356       CONSTRUCTOR_APPEND_ELT (elts, NULL_TREE,
 357                               add_objc_string (METHOD_ENCODING (entries),
 358                                                meth_var_types));
 359
 360       CONSTRUCTOR_APPEND_ELT (inits, NULL_TREE,
 361                               objc_build_constructor (type, elts));
 362
 363       entries = DECL_CHAIN (entries);
 364     }
 365   while (entries);
 366
 367   return objc_build_constructor (build_array_type (type, 0), inits);
 368 }
 369
 370 tree
 371 build_dispatch_table_initializer (tree type, tree entries)
 372 {
 373   vec<constructor_elt, va_gc> *inits = NULL;
 374
 375   do
 376     {
 377       vec<constructor_elt, va_gc> *elems = NULL;
 378       tree expr;
 379
 380       CONSTRUCTOR_APPEND_ELT (elems, NULL_TREE,
 381                               build_selector (METHOD_SEL_NAME (entries)));
 382
 383       /* Generate the method encoding if we don't have one already.  */
 384       if (! METHOD_ENCODING (entries))
 385         METHOD_ENCODING (entries) =
 386           encode_method_prototype (entries);
 387
 388       CONSTRUCTOR_APPEND_ELT (elems, NULL_TREE,
 389                               add_objc_string (METHOD_ENCODING (entries),
 390                                                meth_var_types));
 391
 392       expr = convert (ptr_type_node,
 393                       build_unary_op (input_location, ADDR_EXPR,
 394                                       METHOD_DEFINITION (entries), 1));
 395       CONSTRUCTOR_APPEND_ELT (elems, NULL_TREE, expr);
 396
 397       CONSTRUCTOR_APPEND_ELT (inits, NULL_TREE,
 398                               objc_build_constructor (type, elems));
 399
 400       entries = DECL_CHAIN (entries);
 401     }
 402   while (entries);
 403
 404   return objc_build_constructor (build_array_type (type, 0), inits);
 405 }
 406
 407 /* Used only by build_*_selector_translation_table (). */
 408 void
 409 diagnose_missing_method (tree meth, location_t here)
 410 {
 411   tree method_chain;
 412   bool found = false;
 413   for (method_chain = meth_var_names_chain;
 414        method_chain;
 415        method_chain = TREE_CHAIN (method_chain))
 416     {
 417       if (TREE_VALUE (method_chain) == meth)
 418         {
 419           found = true;
 420           break;
 421         }
 422      }
 423
 424   if (!found)
 425     warning_at (here, 0, "creating selector for nonexistent method %qE",
 426                         meth);
 427 }
 428
 429
 430 static tree
 431 init_module_descriptor (tree type, long vers)
 432 {
 433   tree expr, ltyp;
 434   location_t loc;
 435   vec<constructor_elt, va_gc> *v = NULL;
 436
 437   /* No really useful place to point to.  */
 438   loc = UNKNOWN_LOCATION;
 439
 440   /* version = { 1, ... } */
 441
 442   expr = build_int_cst (long_integer_type_node, vers);
 443   CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, expr);
 444
 445   /* size = { ..., sizeof (struct _objc_module), ... } */
 446
 447   expr = convert (long_integer_type_node,
 448                   size_in_bytes (objc_module_template));
 449   CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, expr);
 450
 451   /* Don't provide any file name for security reasons. */
 452   /* name = { ..., "", ... } */
 453
 454   expr = add_objc_string (get_identifier (""), class_names);
 455   CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, expr);
 456
 457   /* symtab = { ..., _OBJC_SYMBOLS, ... } */
 458
 459   ltyp = build_pointer_type (xref_tag (RECORD_TYPE,
 460                                        get_identifier (UTAG_SYMTAB)));
 461   if (UOBJC_SYMBOLS_decl)
 462     expr = convert (ltyp, build_unary_op (loc,
 463                            ADDR_EXPR, UOBJC_SYMBOLS_decl, 0));
 464   else
 465     expr = convert (ltyp, null_pointer_node);
 466   CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, expr);
 467
 468   return objc_build_constructor (type, v);
 469 }
 470
 471 /* Write out the data structures to describe Objective C classes defined.
 472
 473    struct _objc_module { ... } _OBJC_MODULE = { ... };   */
 474
 475 void
 476 build_module_descriptor (long vers, tree attr)
 477 {
 478   tree decls, *chain = NULL;
 479
 480 #ifdef OBJCPLUS
 481   push_lang_context (lang_name_c); /* extern "C" */
 482 #endif
 483
 484   objc_module_template = objc_start_struct (get_identifier (UTAG_MODULE));
 485
 486   /* long version; */
 487   decls = add_field_decl (long_integer_type_node, "version", &chain);
 488
 489   /* long size; */
 490   add_field_decl (long_integer_type_node, "size", &chain);
 491
 492   /* char *name; */
 493   add_field_decl (string_type_node, "name", &chain);
 494
 495   /* struct _objc_symtab *symtab; */
 496   add_field_decl (build_pointer_type (xref_tag (RECORD_TYPE,
 497                                                 get_identifier (UTAG_SYMTAB))),
 498                   "symtab", &chain);
 499
 500   objc_finish_struct (objc_module_template, decls);
 501
 502   /* Create an instance of "_objc_module".  */
 503   UOBJC_MODULES_decl = start_var_decl (objc_module_template, "_OBJC_Module");
 504
 505   /* This is the root of the metadata for defined classes and categories, it
 506      is referenced by the runtime and, therefore, needed.  */
 507   DECL_PRESERVE_P (UOBJC_MODULES_decl) = 1;
 508
 509   /* Squash `defined but not used' warning.  */
 510   TREE_USED (UOBJC_MODULES_decl) = 1;
 511
 512   /* Allow the runtime to mark meta-data such that it can be assigned to target
 513      specific sections by the back-end.  */
 514   if (attr)
 515     DECL_ATTRIBUTES (UOBJC_MODULES_decl) = attr;
 516
 517   finish_var_decl (UOBJC_MODULES_decl,
 518                    init_module_descriptor (TREE_TYPE (UOBJC_MODULES_decl),
 519                                            vers));
 520
 521 #ifdef OBJCPLUS
 522   pop_lang_context ();
 523 #endif
 524 }
 525
 526 tree
 527 build_ivar_list_initializer (tree type, tree field_decl)
 528 {
 529   vec<constructor_elt, va_gc> *inits = NULL;
 530
 531   for (; field_decl; field_decl = DECL_CHAIN (field_decl))
 532     if (TREE_CODE (field_decl) == FIELD_DECL)
 533       {
 534         vec<constructor_elt, va_gc> *ivar = NULL;
 535         tree id;
 536
 537         /* Set name.  */
 538         if (DECL_NAME (field_decl))
 539           CONSTRUCTOR_APPEND_ELT (ivar, NULL_TREE,
 540                                   add_objc_string (DECL_NAME (field_decl),
 541                                                    meth_var_names));
 542         else
 543           /* Unnamed bit-field ivar (yuck).  */
 544           CONSTRUCTOR_APPEND_ELT (ivar, NULL_TREE,
 545                                   build_int_cst (NULL_TREE, 0));
 546
 547         /* Set type.  */
 548         id = add_objc_string (encode_field_decl (field_decl),
 549                               meth_var_types);
 550         CONSTRUCTOR_APPEND_ELT (ivar, NULL_TREE, id);
 551
 552         /* Set offset.  */
 553         CONSTRUCTOR_APPEND_ELT (ivar, NULL_TREE, byte_position (field_decl));
 554         CONSTRUCTOR_APPEND_ELT (inits, NULL_TREE,
 555                                 objc_build_constructor (type, ivar));
 556     }
 557
 558   return objc_build_constructor (build_array_type (type, 0), inits);
 559 }
 560
 561 /* struct {
 562      int ivar_count;
 563      struct objc_ivar ivar_list[ivar_count];
 564    };  */
 565
 566 tree
 567 build_ivar_list_template (tree list_type, int size)
 568 {
 569   tree objc_ivar_list_record;
 570   tree array_type, decls, *chain = NULL;
 571
 572   objc_ivar_list_record = objc_start_struct (NULL_TREE);
 573
 574   /* int ivar_count; */
 575   decls = add_field_decl (integer_type_node, "ivar_count", &chain);
 576
 577   /* struct objc_ivar ivar_list[]; */
 578   array_type = build_sized_array_type (list_type, size);
 579   add_field_decl (array_type, "ivar_list", &chain);
 580
 581   objc_finish_struct (objc_ivar_list_record, decls);
 582
 583   return objc_ivar_list_record;
 584 }
 585
 586 /* struct _objc_ivar {
 587      char *ivar_name;
 588      char *ivar_type;
 589      int ivar_offset;
 590    };  */
 591
 592 tree
 593 build_ivar_template (void)
 594 {
 595   tree objc_ivar_id, objc_ivar_record;
 596   tree decls, *chain = NULL;
 597
 598   objc_ivar_id = get_identifier (UTAG_IVAR);
 599   objc_ivar_record = objc_start_struct (objc_ivar_id);
 600
 601   /* char *ivar_name; */
 602   decls = add_field_decl (string_type_node, "ivar_name", &chain);
 603
 604   /* char *ivar_type; */
 605   add_field_decl (string_type_node, "ivar_type", &chain);
 606
 607   /* int ivar_offset; */
 608   add_field_decl (integer_type_node, "ivar_offset", &chain);
 609
 610   objc_finish_struct (objc_ivar_record, decls);
 611
 612   return objc_ivar_record;
 613 }
 614
 615 /* Used by NeXT ABI=0..2 */
 616 void
 617 build_next_selector_translation_table (void)
 618 {
 619   tree chain;
 620   for (chain = sel_ref_chain; chain; chain = TREE_CHAIN (chain))
 621     {
 622       tree expr;
 623       tree decl = TREE_PURPOSE (chain);
 624       if (warn_selector)
 625         {
 626           location_t loc;
 627           if (decl)
 628             loc = DECL_SOURCE_LOCATION (decl);
 629           else
 630             loc = UNKNOWN_LOCATION;
 631           diagnose_missing_method (TREE_VALUE (chain), loc);
 632         }
 633
 634       expr = build_selector (TREE_VALUE (chain));
 635
 636       if (decl)
 637         {
 638           /* Entries of this form are used for references to methods.
 639           The runtime re-writes these on start-up, but the compiler can't see
 640           that and optimizes it away unless we force it.  */
 641           DECL_PRESERVE_P (decl) = 1;
 642           finish_var_decl (decl, expr);
 643         }
 644     }
 645 }
 646
 647 void
 648 generate_protocol_references (tree plist)
 649 {
 650   tree lproto;
 651
 652   /* Forward declare protocols referenced.  */
 653   for (lproto = plist; lproto; lproto = TREE_CHAIN (lproto))
 654     {
 655       tree proto = TREE_VALUE (lproto);
 656
 657       if (TREE_CODE (proto) == PROTOCOL_INTERFACE_TYPE
 658           && PROTOCOL_NAME (proto))
 659         {
 660           if (! PROTOCOL_FORWARD_DECL (proto))
 661             PROTOCOL_FORWARD_DECL (proto) = (*runtime.protocol_decl) (proto);
 662
 663           if (PROTOCOL_LIST (proto))
 664             generate_protocol_references (PROTOCOL_LIST (proto));
 665         }
 666     }
 667 }
 668
 669 /* --- new routines --- */
 670
 671 /* Output all strings.  */
 672
 673 /* FIXME: don't use global vars for all this... */
 674
 675 /* This emits all the meta-data string tables (and finalizes each var
 676    as it goes).  */
 677 void
 678 generate_strings (void)
 679 {
 680   tree chain, string_expr;
 681   tree string, decl; /* , type;*/
 682
 683   for (chain = class_names_chain; chain; chain = TREE_CHAIN (chain))
 684     {
 685       string = TREE_VALUE (chain);
 686       decl = TREE_PURPOSE (chain);
 687       string_expr = my_build_string (IDENTIFIER_LENGTH (string) + 1,
 688                                      IDENTIFIER_POINTER (string));
 689       finish_var_decl (decl, string_expr);
 690     }
 691
 692   for (chain = meth_var_names_chain; chain; chain = TREE_CHAIN (chain))
 693     {
 694       string = TREE_VALUE (chain);
 695       decl = TREE_PURPOSE (chain);
 696       string_expr = my_build_string (IDENTIFIER_LENGTH (string) + 1,
 697                                      IDENTIFIER_POINTER (string));
 698       finish_var_decl (decl, string_expr);
 699     }
 700
 701   for (chain = meth_var_types_chain; chain; chain = TREE_CHAIN (chain))
 702     {
 703       string = TREE_VALUE (chain);
 704       decl = TREE_PURPOSE (chain);
 705       string_expr = my_build_string (IDENTIFIER_LENGTH (string) + 1,
 706                                      IDENTIFIER_POINTER (string));
 707       finish_var_decl (decl, string_expr);
 708     }
 709
 710   for (chain = prop_names_attr_chain; chain; chain = TREE_CHAIN (chain))
 711     {
 712       string = TREE_VALUE (chain);
 713       decl = TREE_PURPOSE (chain);
 714       string_expr = my_build_string (IDENTIFIER_LENGTH (string) + 1,
 715                                      IDENTIFIER_POINTER (string));
 716       finish_var_decl (decl, string_expr);
 717     }
 718 }
 719
 720 #include "gt-objc-objc-runtime-shared-support.h"