gcc/d/d-attribs.cc

   1 /* d-attribs.c -- D attributes handling.
   2    Copyright (C) 2015-2021 Free Software Foundation, Inc.
   3
   4 GCC is free software; you can redistribute it and/or modify
   5 it under the terms of the GNU General Public License as published by
   6 the Free Software Foundation; either version 3, or (at your option)
   7 any later version.
   8
   9 GCC is distributed in the hope that it will be useful,
  10 but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 GNU General Public License for more details.
  13
  14 You should have received a copy of the GNU General Public License
  15 along with GCC; see the file COPYING3.  If not see
  16 <http://www.gnu.org/licenses/>.  */
  17
  18 /* Implementation of attribute handlers for user defined attributes and
  19    internal built-in functions.  */
  20
  21 #include "config.h"
  22 #include "system.h"
  23 #include "coretypes.h"
  24
  25 #include "dmd/attrib.h"
  26 #include "dmd/declaration.h"
  27 #include "dmd/mtype.h"
  28
  29 #include "tree.h"
  30 #include "diagnostic.h"
  31 #include "tm.h"
  32 #include "cgraph.h"
  33 #include "toplev.h"
  34 #include "target.h"
  35 #include "common/common-target.h"
  36 #include "stringpool.h"
  37 #include "attribs.h"
  38 #include "varasm.h"
  39
  40 #include "d-tree.h"
  41
  42
  43 /* Internal attribute handlers for built-in functions.  */
  44 static tree handle_noreturn_attribute (tree *, tree, tree, int, bool *);
  45 static tree handle_leaf_attribute (tree *, tree, tree, int, bool *);
  46 static tree handle_const_attribute (tree *, tree, tree, int, bool *);
  47 static tree handle_malloc_attribute (tree *, tree, tree, int, bool *);
  48 static tree handle_pure_attribute (tree *, tree, tree, int, bool *);
  49 static tree handle_novops_attribute (tree *, tree, tree, int, bool *);
  50 static tree handle_nonnull_attribute (tree *, tree, tree, int, bool *);
  51 static tree handle_nothrow_attribute (tree *, tree, tree, int, bool *);
  52 static tree handle_type_generic_attribute (tree *, tree, tree, int, bool *);
  53 static tree handle_transaction_pure_attribute (tree *, tree, tree, int, bool *);
  54 static tree handle_returns_twice_attribute (tree *, tree, tree, int, bool *);
  55 static tree handle_fnspec_attribute (tree *, tree, tree, int, bool *);
  56 static tree handle_always_inline_attribute (tree *, tree, tree, int, bool *);
  57
  58 /* D attribute handlers for user defined attributes.  */
  59 static tree d_handle_noinline_attribute (tree *, tree, tree, int, bool *);
  60 static tree d_handle_forceinline_attribute (tree *, tree, tree, int, bool *);
  61 static tree d_handle_flatten_attribute (tree *, tree, tree, int, bool *);
  62 static tree d_handle_target_attribute (tree *, tree, tree, int, bool *);
  63 static tree d_handle_noclone_attribute (tree *, tree, tree, int, bool *);
  64 static tree d_handle_section_attribute (tree *, tree, tree, int, bool *);
  65 static tree d_handle_alias_attribute (tree *, tree, tree, int, bool *);
  66 static tree d_handle_weak_attribute (tree *, tree, tree, int, bool *) ;
  67
  68 /* Helper to define attribute exclusions.  */
  69 #define ATTR_EXCL(name, function, type, variable)       \
  70   { name, function, type, variable }
  71
  72 /* Define attributes that are mutually exclusive with one another.  */
  73 static const struct attribute_spec::exclusions attr_noreturn_exclusions[] =
  74 {
  75   ATTR_EXCL ("const", true, true, true),
  76   ATTR_EXCL ("malloc", true, true, true),
  77   ATTR_EXCL ("pure", true, true, true),
  78   ATTR_EXCL ("returns_twice", true, true, true),
  79   ATTR_EXCL (NULL, false, false, false),
  80 };
  81
  82 static const struct attribute_spec::exclusions attr_returns_twice_exclusions[] =
  83 {
  84   ATTR_EXCL ("noreturn", true, true, true),
  85   ATTR_EXCL (NULL, false, false, false),
  86 };
  87
  88 static const struct attribute_spec::exclusions attr_const_pure_exclusions[] =
  89 {
  90   ATTR_EXCL ("const", true, true, true),
  91   ATTR_EXCL ("noreturn", true, true, true),
  92   ATTR_EXCL ("pure", true, true, true),
  93   ATTR_EXCL (NULL, false, false, false)
  94 };
  95
  96 static const struct attribute_spec::exclusions attr_inline_exclusions[] =
  97 {
  98   ATTR_EXCL ("noinline", true, true, true),
  99   ATTR_EXCL (NULL, false, false, false),
 100 };
 101
 102 static const struct attribute_spec::exclusions attr_noinline_exclusions[] =
 103 {
 104   ATTR_EXCL ("forceinline", true, true, true),
 105   ATTR_EXCL (NULL, false, false, false),
 106 };
 107
 108 /* Helper to define an attribute.  */
 109 #define ATTR_SPEC(name, min_len, max_len, decl_req, type_req, fn_type_req, \
 110                   affects_type_identity, handler, exclude)                 \
 111   { name, min_len, max_len, decl_req, type_req, fn_type_req,               \
 112     affects_type_identity, handler, exclude }
 113
 114 /* Table of machine-independent attributes.
 115    For internal use (marking of built-ins) only.  */
 116 const attribute_spec d_langhook_common_attribute_table[] =
 117 {
 118   ATTR_SPEC ("noreturn", 0, 0, true, false, false, false,
 119              handle_noreturn_attribute, attr_noreturn_exclusions),
 120   ATTR_SPEC ("leaf", 0, 0, true, false, false, false,
 121              handle_leaf_attribute, NULL),
 122   ATTR_SPEC ("const", 0, 0, true, false, false, false,
 123              handle_const_attribute, attr_const_pure_exclusions),
 124   ATTR_SPEC ("malloc", 0, 0, true, false, false, false,
 125              handle_malloc_attribute, NULL),
 126   ATTR_SPEC ("returns_twice", 0, 0, true, false, false, false,
 127              handle_returns_twice_attribute, attr_returns_twice_exclusions),
 128   ATTR_SPEC ("pure", 0, 0, true, false, false, false,
 129              handle_pure_attribute, attr_const_pure_exclusions),
 130   ATTR_SPEC ("nonnull", 0, -1, false, true, true, false,
 131              handle_nonnull_attribute, NULL),
 132   ATTR_SPEC ("nothrow", 0, 0, true, false, false, false,
 133              handle_nothrow_attribute, NULL),
 134   ATTR_SPEC ("transaction_pure", 0, 0, false, true, true, false,
 135              handle_transaction_pure_attribute, NULL),
 136   ATTR_SPEC ("no vops", 0, 0, true, false, false, false,
 137              handle_novops_attribute, NULL),
 138   ATTR_SPEC ("type generic", 0, 0, false, true, true, false,
 139              handle_type_generic_attribute, NULL),
 140   ATTR_SPEC ("fn spec", 1, 1, false, true, true, false,
 141              handle_fnspec_attribute, NULL),
 142   ATTR_SPEC ("always_inline", 0, 0, true,  false, false, false,
 143              handle_always_inline_attribute, NULL),
 144   ATTR_SPEC (NULL, 0, 0, false, false, false, false, NULL, NULL),
 145 };
 146
 147 /* Table of D language attributes exposed by `gcc.attribute' UDAs.  */
 148 const attribute_spec d_langhook_attribute_table[] =
 149 {
 150   ATTR_SPEC ("noinline", 0, 0, true, false, false, false,
 151              d_handle_noinline_attribute, attr_noinline_exclusions),
 152   ATTR_SPEC ("forceinline", 0, 0, true, false, false, false,
 153              d_handle_forceinline_attribute, attr_inline_exclusions),
 154   ATTR_SPEC ("flatten", 0, 0, true, false, false, false,
 155              d_handle_flatten_attribute, NULL),
 156   ATTR_SPEC ("target", 1, -1, true, false, false, false,
 157              d_handle_target_attribute, NULL),
 158   ATTR_SPEC ("noclone", 0, 0, true, false, false, false,
 159              d_handle_noclone_attribute, NULL),
 160   ATTR_SPEC ("section", 1, 1, true, false, false, false,
 161              d_handle_section_attribute, NULL),
 162   ATTR_SPEC ("alias", 1, 1, true, false, false, false,
 163              d_handle_alias_attribute, NULL),
 164   ATTR_SPEC ("weak", 0, 0, true, false, false, false,
 165              d_handle_weak_attribute, NULL),
 166   ATTR_SPEC (NULL, 0, 0, false, false, false, false, NULL, NULL),
 167 };
 168
 169
 170 /* Insert the type attribute ATTRNAME with value VALUE into TYPE.
 171    Returns a new variant of the original type declaration.  */
 172
 173 tree
 174 insert_type_attribute (tree type, const char *attrname, tree value)
 175 {
 176   tree ident = get_identifier (attrname);
 177
 178   if (value)
 179     value = tree_cons (NULL_TREE, value, NULL_TREE);
 180
 181   tree attribs = merge_attributes (TYPE_ATTRIBUTES (type),
 182                                    tree_cons (ident, value, NULL_TREE));
 183
 184   return build_type_attribute_variant (type, attribs);
 185 }
 186
 187 /* Insert the decl attribute ATTRNAME with value VALUE into DECL.  */
 188
 189 tree
 190 insert_decl_attribute (tree decl, const char *attrname, tree value)
 191 {
 192   tree ident = get_identifier (attrname);
 193
 194   if (value)
 195     value = tree_cons (NULL_TREE, value, NULL_TREE);
 196
 197   tree attribs = merge_attributes (DECL_ATTRIBUTES (decl),
 198                                    tree_cons (ident, value, NULL_TREE));
 199
 200   return build_decl_attribute_variant (decl, attribs);
 201 }
 202
 203 /* Returns TRUE if NAME is an attribute recognized as being handled by
 204    the `gcc.attribute' module.  */
 205
 206 static bool
 207 uda_attribute_p (const char *name)
 208 {
 209   tree ident = get_identifier (name);
 210
 211   /* Search both our language, and target attribute tables.
 212      Common and format attributes are kept internal.  */
 213   for (const attribute_spec *p = d_langhook_attribute_table; p->name; p++)
 214     {
 215       if (get_identifier (p->name) == ident)
 216         return true;
 217     }
 218
 219   if (targetm.attribute_table)
 220     {
 221       for (const attribute_spec *p = targetm.attribute_table; p->name; p++)
 222         {
 223           if (get_identifier (p->name) == ident)
 224             return true;
 225         }
 226     }
 227
 228   return false;
 229 }
 230
 231 /* [attribute/uda]
 232
 233    User Defined Attributes (UDA) are compile time expressions that can be
 234    attached to a declaration.  These attributes can then be queried, extracted,
 235    and manipulated at compile-time.  There is no run-time component to them.
 236
 237    Expand and merge all UDAs found in the EATTRS list that are of type
 238    `gcc.attribute.Attribute'.  This symbol is internally recognized by the
 239    compiler and maps them to their equivalent GCC attribute.  */
 240
 241 static tree
 242 build_attributes (Expressions *eattrs)
 243 {
 244   if (!eattrs)
 245     return NULL_TREE;
 246
 247   expandTuples (eattrs);
 248
 249   tree attribs = NULL_TREE;
 250
 251   for (size_t i = 0; i < eattrs->length; i++)
 252     {
 253       Expression *attr = (*eattrs)[i];
 254       Dsymbol *sym = attr->type->toDsymbol (0);
 255
 256       if (!sym)
 257         continue;
 258
 259       /* Attribute symbol must come from the `gcc.attribute' module.  */
 260       Dsymbol *mod = (Dsymbol *) sym->getModule ();
 261       if (!(strcmp (mod->toChars (), "attribute") == 0
 262             && mod->parent != NULL
 263             && strcmp (mod->parent->toChars (), "gcc") == 0
 264             && !mod->parent->parent))
 265         continue;
 266
 267       /* Get the result of the attribute if it hasn't already been folded.  */
 268       if (attr->op == TOKcall)
 269         attr = attr->ctfeInterpret ();
 270
 271       /* Should now have a struct `Attribute("attrib", "value", ...)'
 272          initializer list.  */
 273       gcc_assert (attr->op == TOKstructliteral);
 274       Expressions *elems = attr->isStructLiteralExp ()->elements;
 275       Expression *e0 = (*elems)[0];
 276
 277       if (e0->op != TOKstring)
 278         {
 279           error ("expected string attribute, not %qs", e0->toChars ());
 280           return error_mark_node;
 281         }
 282
 283       StringExp *se = e0->toStringExp ();
 284       gcc_assert (se->sz == 1);
 285
 286       /* Empty string attribute, just ignore it.  */
 287       if (se->len == 0)
 288         continue;
 289
 290       /* Check if the attribute is recognized and handled.
 291          Done here to report the diagnostic at the right location.  */
 292       const char *name = (const char *)(se->len ? se->string : "");
 293       if (!uda_attribute_p (name))
 294         {
 295           warning_at (make_location_t (e0->loc), OPT_Wattributes,
 296                       "unknown attribute %qs", name);
 297           return error_mark_node;
 298         }
 299
 300       /* Chain all attribute arguments together.  */
 301       tree args = NULL_TREE;
 302
 303       for (size_t j = 1; j < elems->length; j++)
 304         {
 305           Expression *e = (*elems)[j];
 306           StringExp *s = e->isStringExp ();
 307           tree t;
 308           if (s != NULL && s->sz == 1)
 309             {
 310               const char *string = (const char *)(s->len ? s->string : "");
 311               t = build_string (s->len, string);
 312             }
 313           else
 314             t = build_expr (e);
 315
 316           args = chainon (args, build_tree_list (0, t));
 317         }
 318
 319       tree list = build_tree_list (get_identifier (name), args);
 320       attribs = chainon (attribs, list);
 321     }
 322
 323   return attribs;
 324 }
 325
 326 /* If any GCC attributes are found in the declaration SYM, apply them to the
 327    type or decl NODE.  */
 328
 329 void
 330 apply_user_attributes (Dsymbol *sym, tree node)
 331 {
 332   if (!sym->userAttribDecl)
 333     {
 334       if (DECL_P (node) && DECL_ATTRIBUTES (node) != NULL)
 335         decl_attributes (&node, DECL_ATTRIBUTES (node), 0);
 336
 337       return;
 338     }
 339
 340   location_t saved_location = input_location;
 341   input_location = make_location_t (sym->loc);
 342
 343   Expressions *attrs = sym->userAttribDecl->getAttributes ();
 344   decl_attributes (&node, build_attributes (attrs),
 345                    TYPE_P (node) ? ATTR_FLAG_TYPE_IN_PLACE : 0);
 346
 347   input_location = saved_location;
 348 }
 349
 350 /* Built-in attribute handlers.
 351    These functions take the arguments:
 352    (tree *node, tree name, tree args, int flags, bool *no_add_attrs)  */
 353
 354 /* Handle a "noreturn" attribute; arguments as in
 355    struct attribute_spec.handler.  */
 356
 357 static tree
 358 handle_noreturn_attribute (tree *node, tree, tree, int, bool *)
 359 {
 360   tree type = TREE_TYPE (*node);
 361
 362   if (TREE_CODE (*node) == FUNCTION_DECL)
 363     TREE_THIS_VOLATILE (*node) = 1;
 364   else if (TREE_CODE (type) == POINTER_TYPE
 365            && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE)
 366     TREE_TYPE (*node)
 367       = build_pointer_type
 368         (build_type_variant (TREE_TYPE (type),
 369                              TYPE_READONLY (TREE_TYPE (type)), 1));
 370   else
 371     gcc_unreachable ();
 372
 373   return NULL_TREE;
 374 }
 375
 376 /* Handle a "leaf" attribute; arguments as in
 377    struct attribute_spec.handler.  */
 378
 379 static tree
 380 handle_leaf_attribute (tree *node, tree name, tree, int, bool *no_add_attrs)
 381 {
 382   if (TREE_CODE (*node) != FUNCTION_DECL)
 383     {
 384       warning (OPT_Wattributes, "%qE attribute ignored", name);
 385       *no_add_attrs = true;
 386     }
 387   if (!TREE_PUBLIC (*node))
 388     {
 389       warning (OPT_Wattributes, "%qE attribute has no effect", name);
 390       *no_add_attrs = true;
 391     }
 392
 393   return NULL_TREE;
 394 }
 395
 396 /* Handle a "const" attribute; arguments as in
 397    struct attribute_spec.handler.  */
 398
 399 static tree
 400 handle_const_attribute (tree *node, tree, tree, int, bool *)
 401 {
 402   tree type = TREE_TYPE (*node);
 403
 404   if (TREE_CODE (*node) == FUNCTION_DECL)
 405     TREE_READONLY (*node) = 1;
 406   else if (TREE_CODE (type) == POINTER_TYPE
 407            && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE)
 408     TREE_TYPE (*node)
 409       = build_pointer_type
 410         (build_type_variant (TREE_TYPE (type), 1,
 411                              TREE_THIS_VOLATILE (TREE_TYPE (type))));
 412   else
 413     gcc_unreachable ();
 414
 415   return NULL_TREE;
 416 }
 417
 418 /* Handle a "malloc" attribute; arguments as in
 419    struct attribute_spec.handler.  */
 420
 421 tree
 422 handle_malloc_attribute (tree *node, tree, tree, int, bool *)
 423 {
 424   gcc_assert (TREE_CODE (*node) == FUNCTION_DECL
 425               && POINTER_TYPE_P (TREE_TYPE (TREE_TYPE (*node))));
 426   DECL_IS_MALLOC (*node) = 1;
 427   return NULL_TREE;
 428 }
 429
 430 /* Handle a "pure" attribute; arguments as in
 431    struct attribute_spec.handler.  */
 432
 433 static tree
 434 handle_pure_attribute (tree *node, tree, tree, int, bool *)
 435 {
 436   gcc_assert (TREE_CODE (*node) == FUNCTION_DECL);
 437   DECL_PURE_P (*node) = 1;
 438   return NULL_TREE;
 439 }
 440
 441 /* Handle a "no vops" attribute; arguments as in
 442    struct attribute_spec.handler.  */
 443
 444 static tree
 445 handle_novops_attribute (tree *node, tree, tree, int, bool *)
 446 {
 447   gcc_assert (TREE_CODE (*node) == FUNCTION_DECL);
 448   DECL_IS_NOVOPS (*node) = 1;
 449   return NULL_TREE;
 450 }
 451
 452 /* Helper for nonnull attribute handling; fetch the operand number
 453    from the attribute argument list.  */
 454
 455 static bool
 456 get_nonnull_operand (tree arg_num_expr, unsigned HOST_WIDE_INT *valp)
 457 {
 458   /* Verify the arg number is a constant.  */
 459   if (!tree_fits_uhwi_p (arg_num_expr))
 460     return false;
 461
 462   *valp = TREE_INT_CST_LOW (arg_num_expr);
 463   return true;
 464 }
 465
 466 /* Handle the "nonnull" attribute.  */
 467
 468 static tree
 469 handle_nonnull_attribute (tree *node, tree, tree args, int, bool *)
 470 {
 471   tree type = *node;
 472
 473   /* If no arguments are specified, all pointer arguments should be
 474      non-null.  Verify a full prototype is given so that the arguments
 475      will have the correct types when we actually check them later.
 476      Avoid diagnosing type-generic built-ins since those have no
 477      prototype.  */
 478   if (!args)
 479     {
 480       gcc_assert (prototype_p (type)
 481                   || !TYPE_ATTRIBUTES (type)
 482                   || lookup_attribute ("type generic", TYPE_ATTRIBUTES (type)));
 483
 484       return NULL_TREE;
 485     }
 486
 487   /* Argument list specified.  Verify that each argument number references
 488      a pointer argument.  */
 489   for (; args; args = TREE_CHAIN (args))
 490     {
 491       tree argument;
 492       unsigned HOST_WIDE_INT arg_num = 0, ck_num;
 493
 494       if (!get_nonnull_operand (TREE_VALUE (args), &arg_num))
 495         gcc_unreachable ();
 496
 497       argument = TYPE_ARG_TYPES (type);
 498       if (argument)
 499         {
 500           for (ck_num = 1; ; ck_num++)
 501             {
 502               if (!argument || ck_num == arg_num)
 503                 break;
 504               argument = TREE_CHAIN (argument);
 505             }
 506
 507           gcc_assert (argument
 508                       && TREE_CODE (TREE_VALUE (argument)) == POINTER_TYPE);
 509         }
 510     }
 511
 512   return NULL_TREE;
 513 }
 514
 515 /* Handle a "nothrow" attribute; arguments as in
 516    struct attribute_spec.handler.  */
 517
 518 static tree
 519 handle_nothrow_attribute (tree *node, tree, tree, int, bool *)
 520 {
 521   gcc_assert (TREE_CODE (*node) == FUNCTION_DECL);
 522   TREE_NOTHROW (*node) = 1;
 523   return NULL_TREE;
 524 }
 525
 526 /* Handle a "type_generic" attribute.  */
 527
 528 static tree
 529 handle_type_generic_attribute (tree *node, tree, tree, int, bool *)
 530 {
 531   /* Ensure we have a function type.  */
 532   gcc_assert (TREE_CODE (*node) == FUNCTION_TYPE);
 533
 534   /* Ensure we have a variadic function.  */
 535   gcc_assert (!prototype_p (*node) || stdarg_p (*node));
 536
 537   return NULL_TREE;
 538 }
 539
 540 /* Handle a "transaction_pure" attribute.  */
 541
 542 static tree
 543 handle_transaction_pure_attribute (tree *node, tree, tree, int, bool *)
 544 {
 545   /* Ensure we have a function type.  */
 546   gcc_assert (TREE_CODE (*node) == FUNCTION_TYPE);
 547
 548   return NULL_TREE;
 549 }
 550
 551 /* Handle a "returns_twice" attribute.  */
 552
 553 static tree
 554 handle_returns_twice_attribute (tree *node, tree, tree, int, bool *)
 555 {
 556   gcc_assert (TREE_CODE (*node) == FUNCTION_DECL);
 557
 558   DECL_IS_RETURNS_TWICE (*node) = 1;
 559
 560   return NULL_TREE;
 561 }
 562
 563 /* Handle a "fn spec" attribute; arguments as in
 564    struct attribute_spec.handler.  */
 565
 566 tree
 567 handle_fnspec_attribute (tree *, tree, tree args, int, bool *)
 568 {
 569   gcc_assert (args
 570               && TREE_CODE (TREE_VALUE (args)) == STRING_CST
 571               && !TREE_CHAIN (args));
 572   return NULL_TREE;
 573 }
 574
 575 /* Handle a "always_inline" attribute; arguments as in
 576    struct attribute_spec.handler.  */
 577
 578 static tree
 579 handle_always_inline_attribute (tree *node, tree, tree, int, bool *)
 580 {
 581   gcc_assert (TREE_CODE (*node) == FUNCTION_DECL);
 582
 583   return NULL_TREE;
 584 }
 585
 586 /* Language specific attribute handlers.
 587    These functions take the arguments:
 588    (tree *node, tree name, tree args, int flags, bool *no_add_attrs)  */
 589
 590 /* Handle a "noinline" attribute.  */
 591
 592 static tree
 593 d_handle_noinline_attribute (tree *node, tree name, tree, int,
 594                              bool *no_add_attrs)
 595 {
 596   Type *t = TYPE_LANG_FRONTEND (TREE_TYPE (*node));
 597
 598   if (t->ty == Tfunction)
 599     DECL_UNINLINABLE (*node) = 1;
 600   else
 601     {
 602       warning (OPT_Wattributes, "%qE attribute ignored", name);
 603       *no_add_attrs = true;
 604     }
 605
 606   return NULL_TREE;
 607 }
 608
 609 /* Handle a "forceinline" attribute.  */
 610
 611 static tree
 612 d_handle_forceinline_attribute (tree *node, tree name, tree, int,
 613                                 bool *no_add_attrs)
 614 {
 615   Type *t = TYPE_LANG_FRONTEND (TREE_TYPE (*node));
 616
 617   if (t->ty == Tfunction)
 618     {
 619       tree attributes = DECL_ATTRIBUTES (*node);
 620
 621       /* Push attribute always_inline.  */
 622       if (!lookup_attribute ("always_inline", attributes))
 623         DECL_ATTRIBUTES (*node) = tree_cons (get_identifier ("always_inline"),
 624                                              NULL_TREE, attributes);
 625
 626       DECL_DECLARED_INLINE_P (*node) = 1;
 627       DECL_NO_INLINE_WARNING_P (*node) = 1;
 628       DECL_DISREGARD_INLINE_LIMITS (*node) = 1;
 629     }
 630   else
 631     {
 632       warning (OPT_Wattributes, "%qE attribute ignored", name);
 633       *no_add_attrs = true;
 634     }
 635
 636   return NULL_TREE;
 637 }
 638
 639 /* Handle a "flatten" attribute.  */
 640
 641 static tree
 642 d_handle_flatten_attribute (tree *node, tree name, tree, int,
 643                             bool *no_add_attrs)
 644 {
 645   Type *t = TYPE_LANG_FRONTEND (TREE_TYPE (*node));
 646
 647   if (t->ty != Tfunction)
 648     {
 649       warning (OPT_Wattributes, "%qE attribute ignored", name);
 650       *no_add_attrs = true;
 651     }
 652
 653   return NULL_TREE;
 654 }
 655
 656 /* Handle a "target" attribute.  */
 657
 658 static tree
 659 d_handle_target_attribute (tree *node, tree name, tree args, int flags,
 660                            bool *no_add_attrs)
 661 {
 662   Type *t = TYPE_LANG_FRONTEND (TREE_TYPE (*node));
 663
 664   /* Ensure we have a function type.  */
 665   if (t->ty != Tfunction)
 666     {
 667       warning (OPT_Wattributes, "%qE attribute ignored", name);
 668       *no_add_attrs = true;
 669     }
 670   else if (!targetm.target_option.valid_attribute_p (*node, name, args, flags))
 671     *no_add_attrs = true;
 672
 673   return NULL_TREE;
 674 }
 675
 676 /* Handle a "noclone" attribute.  */
 677
 678 static tree
 679 d_handle_noclone_attribute (tree *node, tree name, tree, int,
 680                             bool *no_add_attrs)
 681 {
 682   Type *t = TYPE_LANG_FRONTEND (TREE_TYPE (*node));
 683
 684   if (t->ty == Tfunction)
 685     {
 686       tree attributes = DECL_ATTRIBUTES (*node);
 687
 688       /* Push attribute noclone.  */
 689       if (!lookup_attribute ("noclone", attributes))
 690         DECL_ATTRIBUTES (*node) = tree_cons (get_identifier ("noclone"),
 691                                              NULL_TREE, attributes);
 692     }
 693   else
 694     {
 695       warning (OPT_Wattributes, "%qE attribute ignored", name);
 696       *no_add_attrs = true;
 697     }
 698
 699   return NULL_TREE;
 700 }
 701
 702 /* Handle a "section" attribute; arguments as in
 703    struct attribute_spec.handler.  */
 704
 705 static tree
 706 d_handle_section_attribute (tree *node, tree, tree args, int,
 707                             bool *no_add_attrs)
 708 {
 709   tree decl = *node;
 710
 711   if (targetm_common.have_named_sections)
 712     {
 713       if (VAR_OR_FUNCTION_DECL_P (decl)
 714           && TREE_CODE (TREE_VALUE (args)) == STRING_CST)
 715         {
 716           if (VAR_P (decl)
 717               && current_function_decl != NULL_TREE
 718               && !TREE_STATIC (decl))
 719             {
 720               error_at (DECL_SOURCE_LOCATION (decl),
 721                         "section attribute cannot be specified for "
 722                         "local variables");
 723               *no_add_attrs = true;
 724             }
 725
 726           /* The decl may have already been given a section attribute
 727              from a previous declaration.  Ensure they match.  */
 728           else if (DECL_SECTION_NAME (decl) != NULL
 729                    && strcmp (DECL_SECTION_NAME (decl),
 730                               TREE_STRING_POINTER (TREE_VALUE (args))) != 0)
 731             {
 732               error ("section of %q+D conflicts with previous declaration",
 733                      *node);
 734               *no_add_attrs = true;
 735             }
 736           else if (VAR_P (decl)
 737                    && !targetm.have_tls && targetm.emutls.tmpl_section
 738                    && DECL_THREAD_LOCAL_P (decl))
 739             {
 740               error ("section of %q+D cannot be overridden", *node);
 741               *no_add_attrs = true;
 742             }
 743           else
 744             set_decl_section_name (decl,
 745                                    TREE_STRING_POINTER (TREE_VALUE (args)));
 746         }
 747       else
 748         {
 749           error ("section attribute not allowed for %q+D", *node);
 750           *no_add_attrs = true;
 751         }
 752     }
 753   else
 754     {
 755       error_at (DECL_SOURCE_LOCATION (*node),
 756                 "section attributes are not supported for this target");
 757       *no_add_attrs = true;
 758     }
 759
 760   return NULL_TREE;
 761 }
 762
 763 /* Handle an "alias" attribute; arguments as in
 764    struct attribute_spec.handler.  */
 765
 766 static tree
 767 d_handle_alias_attribute (tree *node, tree name, tree args, int,
 768                           bool *no_add_attrs)
 769 {
 770   tree decl = *node;
 771
 772   if (TREE_CODE (decl) != FUNCTION_DECL
 773       && TREE_CODE (decl) != VAR_DECL)
 774     {
 775       warning (OPT_Wattributes, "%qE attribute ignored", name);
 776       *no_add_attrs = true;
 777       return NULL_TREE;
 778     }
 779   else if ((TREE_CODE (decl) == FUNCTION_DECL && DECL_INITIAL (decl))
 780       || (TREE_CODE (decl) != FUNCTION_DECL
 781           && TREE_PUBLIC (decl) && !DECL_EXTERNAL (decl))
 782       /* A static variable declaration is always a tentative definition,
 783          but the alias is a non-tentative definition which overrides.  */
 784       || (TREE_CODE (decl) != FUNCTION_DECL
 785           && !TREE_PUBLIC (decl) && DECL_INITIAL (decl)))
 786     {
 787       error ("%q+D defined both normally and as %qE attribute", decl, name);
 788       *no_add_attrs = true;
 789       return NULL_TREE;
 790     }
 791   else if (decl_function_context (decl))
 792     {
 793       error ("%q+D alias functions must be global", name);
 794       *no_add_attrs = true;
 795       return NULL_TREE;
 796     }
 797   else
 798     {
 799       tree id;
 800
 801       id = TREE_VALUE (args);
 802       if (TREE_CODE (id) != STRING_CST)
 803         {
 804           error ("attribute %qE argument not a string", name);
 805           *no_add_attrs = true;
 806           return NULL_TREE;
 807         }
 808       id = get_identifier (TREE_STRING_POINTER (id));
 809       /* This counts as a use of the object pointed to.  */
 810       TREE_USED (id) = 1;
 811
 812       if (TREE_CODE (decl) == FUNCTION_DECL)
 813         DECL_INITIAL (decl) = error_mark_node;
 814       else
 815         TREE_STATIC (decl) = 1;
 816
 817       return NULL_TREE;
 818     }
 819 }
 820
 821 /* Handle a "weak" attribute; arguments as in
 822    struct attribute_spec.handler.  */
 823
 824 static tree
 825 d_handle_weak_attribute (tree *node, tree name, tree, int, bool *no_add_attrs)
 826 {
 827   if (TREE_CODE (*node) == FUNCTION_DECL
 828       && DECL_DECLARED_INLINE_P (*node))
 829     {
 830       warning (OPT_Wattributes, "inline function %q+D declared weak", *node);
 831       *no_add_attrs = true;
 832     }
 833   else if (VAR_OR_FUNCTION_DECL_P (*node))
 834     {
 835       struct symtab_node *n = symtab_node::get (*node);
 836       if (n && n->refuse_visibility_changes)
 837         error ("%q+D declared weak after being used", *node);
 838       declare_weak (*node);
 839     }
 840   else
 841     warning (OPT_Wattributes, "%qE attribute ignored", name);
 842
 843   return NULL_TREE;
 844 }
 845