1 /* Process declarations and variables for C++ compiler. 2 Copyright (C) 1988-2013 Free Software Foundation, Inc. 3 Hacked by Michael Tiemann (tiemann@cygnus.com) 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 22 /* Process declarations and symbol lookup for C++ front end. 23 Also constructs types; the standard scalar types at initialization, 24 and structure, union, array and enum types when they are declared. */ 25 26 /* ??? not all decl nodes are given the most useful possible 27 line numbers. For example, the CONST_DECLs for enum values. */ 28 29 #include "config.h" 30 #include "system.h" 31 #include "coretypes.h" 32 #include "tm.h" 33 #include "tree.h" 34 #include "flags.h" 35 #include "cp-tree.h" 36 #include "decl.h" 37 #include "toplev.h" 38 #include "timevar.h" 39 #include "cpplib.h" 40 #include "target.h" 41 #include "c-family/c-common.h" 42 #include "c-family/c-objc.h" 43 #include "cgraph.h" 44 #include "tree-inline.h" 45 #include "c-family/c-pragma.h" 46 #include "dumpfile.h" 47 #include "intl.h" 48 #include "gimple.h" 49 #include "pointer-set.h" 50 #include "splay-tree.h" 51 #include "langhooks.h" 52 #include "c-family/c-ada-spec.h" 53 54 extern cpp_reader *parse_in; 55 56 /* This structure contains information about the initializations 57 and/or destructions required for a particular priority level. */ 58 typedef struct priority_info_s { 59 /* Nonzero if there have been any initializations at this priority 60 throughout the translation unit. */ 61 int initializations_p; 62 /* Nonzero if there have been any destructions at this priority 63 throughout the translation unit. */ 64 int destructions_p; 65 } *priority_info; 66 67 static void mark_vtable_entries (tree); 68 static bool maybe_emit_vtables (tree); 69 static bool acceptable_java_type (tree); 70 static tree start_objects (int, int); 71 static void finish_objects (int, int, tree); 72 static tree start_static_storage_duration_function (unsigned); 73 static void finish_static_storage_duration_function (tree); 74 static priority_info get_priority_info (int); 75 static void do_static_initialization_or_destruction (tree, bool); 76 static void one_static_initialization_or_destruction (tree, tree, bool); 77 static void generate_ctor_or_dtor_function (bool, int, location_t *); 78 static int generate_ctor_and_dtor_functions_for_priority (splay_tree_node, 79 void *); 80 static tree prune_vars_needing_no_initialization (tree *); 81 static void write_out_vars (tree); 82 static void import_export_class (tree); 83 static tree get_guard_bits (tree); 84 static void determine_visibility_from_class (tree, tree); 85 static bool determine_hidden_inline (tree); 86 static bool decl_defined_p (tree); 87 88 /* A list of static class variables. This is needed, because a 89 static class variable can be declared inside the class without 90 an initializer, and then initialized, statically, outside the class. */ 91 static GTY(()) vec<tree, va_gc> *pending_statics; 92 93 /* A list of functions which were declared inline, but which we 94 may need to emit outline anyway. */ 95 static GTY(()) vec<tree, va_gc> *deferred_fns; 96 97 /* A list of decls that use types with no linkage, which we need to make 98 sure are defined. */ 99 static GTY(()) vec<tree, va_gc> *no_linkage_decls; 100 101 /* Nonzero if we're done parsing and into end-of-file activities. */ 102 103 int at_eof; 104 105 106 107 /* Return a member function type (a METHOD_TYPE), given FNTYPE (a 108 FUNCTION_TYPE), CTYPE (class type), and QUALS (the cv-qualifiers 109 that apply to the function). */ 110 111 tree 112 build_memfn_type (tree fntype, tree ctype, cp_cv_quals quals, 113 cp_ref_qualifier rqual) 114 { 115 tree raises; 116 tree attrs; 117 int type_quals; 118 119 if (fntype == error_mark_node || ctype == error_mark_node) 120 return error_mark_node; 121 122 gcc_assert (TREE_CODE (fntype) == FUNCTION_TYPE 123 || TREE_CODE (fntype) == METHOD_TYPE); 124 125 type_quals = quals & ~TYPE_QUAL_RESTRICT; 126 ctype = cp_build_qualified_type (ctype, type_quals); 127 raises = TYPE_RAISES_EXCEPTIONS (fntype); 128 attrs = TYPE_ATTRIBUTES (fntype); 129 fntype = build_method_type_directly (ctype, TREE_TYPE (fntype), 130 (TREE_CODE (fntype) == METHOD_TYPE 131 ? TREE_CHAIN (TYPE_ARG_TYPES (fntype)) 132 : TYPE_ARG_TYPES (fntype))); 133 if (attrs) 134 fntype = cp_build_type_attribute_variant (fntype, attrs); 135 if (rqual) 136 fntype = build_ref_qualified_type (fntype, rqual); 137 if (raises) 138 fntype = build_exception_variant (fntype, raises); 139 140 return fntype; 141 } 142 143 /* Return a variant of FNTYPE, a FUNCTION_TYPE or METHOD_TYPE, with its 144 return type changed to NEW_RET. */ 145 146 tree 147 change_return_type (tree new_ret, tree fntype) 148 { 149 tree newtype; 150 tree args = TYPE_ARG_TYPES (fntype); 151 tree raises = TYPE_RAISES_EXCEPTIONS (fntype); 152 tree attrs = TYPE_ATTRIBUTES (fntype); 153 154 if (new_ret == error_mark_node) 155 return fntype; 156 157 if (same_type_p (new_ret, TREE_TYPE (fntype))) 158 return fntype; 159 160 if (TREE_CODE (fntype) == FUNCTION_TYPE) 161 { 162 newtype = build_function_type (new_ret, args); 163 newtype = apply_memfn_quals (newtype, 164 type_memfn_quals (fntype), 165 type_memfn_rqual (fntype)); 166 } 167 else 168 newtype = build_method_type_directly 169 (class_of_this_parm (fntype), new_ret, TREE_CHAIN (args)); 170 if (raises) 171 newtype = build_exception_variant (newtype, raises); 172 if (attrs) 173 newtype = cp_build_type_attribute_variant (newtype, attrs); 174 175 return newtype; 176 } 177 178 /* Build a PARM_DECL with NAME and TYPE, and set DECL_ARG_TYPE 179 appropriately. */ 180 181 tree 182 cp_build_parm_decl (tree name, tree type) 183 { 184 tree parm = build_decl (input_location, 185 PARM_DECL, name, type); 186 /* DECL_ARG_TYPE is only used by the back end and the back end never 187 sees templates. */ 188 if (!processing_template_decl) 189 DECL_ARG_TYPE (parm) = type_passed_as (type); 190 191 /* If the type is a pack expansion, then we have a function 192 parameter pack. */ 193 if (type && TREE_CODE (type) == TYPE_PACK_EXPANSION) 194 FUNCTION_PARAMETER_PACK_P (parm) = 1; 195 196 return parm; 197 } 198 199 /* Returns a PARM_DECL for a parameter of the indicated TYPE, with the 200 indicated NAME. */ 201 202 tree 203 build_artificial_parm (tree name, tree type) 204 { 205 tree parm = cp_build_parm_decl (name, type); 206 DECL_ARTIFICIAL (parm) = 1; 207 /* All our artificial parms are implicitly `const'; they cannot be 208 assigned to. */ 209 TREE_READONLY (parm) = 1; 210 return parm; 211 } 212 213 /* Constructors for types with virtual baseclasses need an "in-charge" flag 214 saying whether this constructor is responsible for initialization of 215 virtual baseclasses or not. All destructors also need this "in-charge" 216 flag, which additionally determines whether or not the destructor should 217 free the memory for the object. 218 219 This function adds the "in-charge" flag to member function FN if 220 appropriate. It is called from grokclassfn and tsubst. 221 FN must be either a constructor or destructor. 222 223 The in-charge flag follows the 'this' parameter, and is followed by the 224 VTT parm (if any), then the user-written parms. */ 225 226 void 227 maybe_retrofit_in_chrg (tree fn) 228 { 229 tree basetype, arg_types, parms, parm, fntype; 230 231 /* If we've already add the in-charge parameter don't do it again. */ 232 if (DECL_HAS_IN_CHARGE_PARM_P (fn)) 233 return; 234 235 /* When processing templates we can't know, in general, whether or 236 not we're going to have virtual baseclasses. */ 237 if (processing_template_decl) 238 return; 239 240 /* We don't need an in-charge parameter for constructors that don't 241 have virtual bases. */ 242 if (DECL_CONSTRUCTOR_P (fn) 243 && !CLASSTYPE_VBASECLASSES (DECL_CONTEXT (fn))) 244 return; 245 246 arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn)); 247 basetype = TREE_TYPE (TREE_VALUE (arg_types)); 248 arg_types = TREE_CHAIN (arg_types); 249 250 parms = DECL_CHAIN (DECL_ARGUMENTS (fn)); 251 252 /* If this is a subobject constructor or destructor, our caller will 253 pass us a pointer to our VTT. */ 254 if (CLASSTYPE_VBASECLASSES (DECL_CONTEXT (fn))) 255 { 256 parm = build_artificial_parm (vtt_parm_identifier, vtt_parm_type); 257 258 /* First add it to DECL_ARGUMENTS between 'this' and the real args... */ 259 DECL_CHAIN (parm) = parms; 260 parms = parm; 261 262 /* ...and then to TYPE_ARG_TYPES. */ 263 arg_types = hash_tree_chain (vtt_parm_type, arg_types); 264 265 DECL_HAS_VTT_PARM_P (fn) = 1; 266 } 267 268 /* Then add the in-charge parm (before the VTT parm). */ 269 parm = build_artificial_parm (in_charge_identifier, integer_type_node); 270 DECL_CHAIN (parm) = parms; 271 parms = parm; 272 arg_types = hash_tree_chain (integer_type_node, arg_types); 273 274 /* Insert our new parameter(s) into the list. */ 275 DECL_CHAIN (DECL_ARGUMENTS (fn)) = parms; 276 277 /* And rebuild the function type. */ 278 fntype = build_method_type_directly (basetype, TREE_TYPE (TREE_TYPE (fn)), 279 arg_types); 280 if (TYPE_RAISES_EXCEPTIONS (TREE_TYPE (fn))) 281 fntype = build_exception_variant (fntype, 282 TYPE_RAISES_EXCEPTIONS (TREE_TYPE (fn))); 283 if (TYPE_ATTRIBUTES (TREE_TYPE (fn))) 284 fntype = (cp_build_type_attribute_variant 285 (fntype, TYPE_ATTRIBUTES (TREE_TYPE (fn)))); 286 TREE_TYPE (fn) = fntype; 287 288 /* Now we've got the in-charge parameter. */ 289 DECL_HAS_IN_CHARGE_PARM_P (fn) = 1; 290 } 291 292 /* Classes overload their constituent function names automatically. 293 When a function name is declared in a record structure, 294 its name is changed to it overloaded name. Since names for 295 constructors and destructors can conflict, we place a leading 296 '$' for destructors. 297 298 CNAME is the name of the class we are grokking for. 299 300 FUNCTION is a FUNCTION_DECL. It was created by `grokdeclarator'. 301 302 FLAGS contains bits saying what's special about today's 303 arguments. DTOR_FLAG == DESTRUCTOR. 304 305 If FUNCTION is a destructor, then we must add the `auto-delete' field 306 as a second parameter. There is some hair associated with the fact 307 that we must "declare" this variable in the manner consistent with the 308 way the rest of the arguments were declared. 309 310 QUALS are the qualifiers for the this pointer. */ 311 312 void 313 grokclassfn (tree ctype, tree function, enum overload_flags flags) 314 { 315 tree fn_name = DECL_NAME (function); 316 317 /* Even within an `extern "C"' block, members get C++ linkage. See 318 [dcl.link] for details. */ 319 SET_DECL_LANGUAGE (function, lang_cplusplus); 320 321 if (fn_name == NULL_TREE) 322 { 323 error ("name missing for member function"); 324 fn_name = get_identifier ("<anonymous>"); 325 DECL_NAME (function) = fn_name; 326 } 327 328 DECL_CONTEXT (function) = ctype; 329 330 if (flags == DTOR_FLAG) 331 DECL_DESTRUCTOR_P (function) = 1; 332 333 if (flags == DTOR_FLAG || DECL_CONSTRUCTOR_P (function)) 334 maybe_retrofit_in_chrg (function); 335 } 336 337 /* Create an ARRAY_REF, checking for the user doing things backwards 338 along the way. DECLTYPE_P is for N3276, as in the parser. */ 339 340 tree 341 grok_array_decl (location_t loc, tree array_expr, tree index_exp, 342 bool decltype_p) 343 { 344 tree type; 345 tree expr; 346 tree orig_array_expr = array_expr; 347 tree orig_index_exp = index_exp; 348 349 if (error_operand_p (array_expr) || error_operand_p (index_exp)) 350 return error_mark_node; 351 352 if (processing_template_decl) 353 { 354 if (type_dependent_expression_p (array_expr) 355 || type_dependent_expression_p (index_exp)) 356 return build_min_nt_loc (loc, ARRAY_REF, array_expr, index_exp, 357 NULL_TREE, NULL_TREE); 358 array_expr = build_non_dependent_expr (array_expr); 359 index_exp = build_non_dependent_expr (index_exp); 360 } 361 362 type = TREE_TYPE (array_expr); 363 gcc_assert (type); 364 type = non_reference (type); 365 366 /* If they have an `operator[]', use that. */ 367 if (MAYBE_CLASS_TYPE_P (type) || MAYBE_CLASS_TYPE_P (TREE_TYPE (index_exp))) 368 { 369 tsubst_flags_t complain = tf_warning_or_error; 370 if (decltype_p) 371 complain |= tf_decltype; 372 expr = build_new_op (loc, ARRAY_REF, LOOKUP_NORMAL, array_expr, 373 index_exp, NULL_TREE, /*overload=*/NULL, complain); 374 } 375 else 376 { 377 tree p1, p2, i1, i2; 378 379 /* Otherwise, create an ARRAY_REF for a pointer or array type. 380 It is a little-known fact that, if `a' is an array and `i' is 381 an int, you can write `i[a]', which means the same thing as 382 `a[i]'. */ 383 if (TREE_CODE (type) == ARRAY_TYPE || TREE_CODE (type) == VECTOR_TYPE) 384 p1 = array_expr; 385 else 386 p1 = build_expr_type_conversion (WANT_POINTER, array_expr, false); 387 388 if (TREE_CODE (TREE_TYPE (index_exp)) == ARRAY_TYPE) 389 p2 = index_exp; 390 else 391 p2 = build_expr_type_conversion (WANT_POINTER, index_exp, false); 392 393 i1 = build_expr_type_conversion (WANT_INT | WANT_ENUM, array_expr, 394 false); 395 i2 = build_expr_type_conversion (WANT_INT | WANT_ENUM, index_exp, 396 false); 397 398 if ((p1 && i2) && (i1 && p2)) 399 error ("ambiguous conversion for array subscript"); 400 401 if (p1 && i2) 402 array_expr = p1, index_exp = i2; 403 else if (i1 && p2) 404 array_expr = p2, index_exp = i1; 405 else 406 { 407 error ("invalid types %<%T[%T]%> for array subscript", 408 type, TREE_TYPE (index_exp)); 409 return error_mark_node; 410 } 411 412 if (array_expr == error_mark_node || index_exp == error_mark_node) 413 error ("ambiguous conversion for array subscript"); 414 415 expr = build_array_ref (input_location, array_expr, index_exp); 416 } 417 if (processing_template_decl && expr != error_mark_node) 418 return build_min_non_dep (ARRAY_REF, expr, orig_array_expr, orig_index_exp, 419 NULL_TREE, NULL_TREE); 420 return expr; 421 } 422 423 /* Given the cast expression EXP, checking out its validity. Either return 424 an error_mark_node if there was an unavoidable error, return a cast to 425 void for trying to delete a pointer w/ the value 0, or return the 426 call to delete. If DOING_VEC is true, we handle things differently 427 for doing an array delete. 428 Implements ARM $5.3.4. This is called from the parser. */ 429 430 tree 431 delete_sanity (tree exp, tree size, bool doing_vec, int use_global_delete, 432 tsubst_flags_t complain) 433 { 434 tree t, type; 435 436 if (exp == error_mark_node) 437 return exp; 438 439 if (processing_template_decl) 440 { 441 t = build_min (DELETE_EXPR, void_type_node, exp, size); 442 DELETE_EXPR_USE_GLOBAL (t) = use_global_delete; 443 DELETE_EXPR_USE_VEC (t) = doing_vec; 444 TREE_SIDE_EFFECTS (t) = 1; 445 return t; 446 } 447 448 /* An array can't have been allocated by new, so complain. */ 449 if (TREE_CODE (TREE_TYPE (exp)) == ARRAY_TYPE) 450 warning (0, "deleting array %q#E", exp); 451 452 t = build_expr_type_conversion (WANT_POINTER, exp, true); 453 454 if (t == NULL_TREE || t == error_mark_node) 455 { 456 error ("type %q#T argument given to %<delete%>, expected pointer", 457 TREE_TYPE (exp)); 458 return error_mark_node; 459 } 460 461 type = TREE_TYPE (t); 462 463 /* As of Valley Forge, you can delete a pointer to const. */ 464 465 /* You can't delete functions. */ 466 if (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE) 467 { 468 error ("cannot delete a function. Only pointer-to-objects are " 469 "valid arguments to %<delete%>"); 470 return error_mark_node; 471 } 472 473 /* Deleting ptr to void is undefined behavior [expr.delete/3]. */ 474 if (TREE_CODE (TREE_TYPE (type)) == VOID_TYPE) 475 { 476 warning (0, "deleting %qT is undefined", type); 477 doing_vec = 0; 478 } 479 480 /* Deleting a pointer with the value zero is valid and has no effect. */ 481 if (integer_zerop (t)) 482 return build1 (NOP_EXPR, void_type_node, t); 483 484 if (doing_vec) 485 return build_vec_delete (t, /*maxindex=*/NULL_TREE, 486 sfk_deleting_destructor, 487 use_global_delete, complain); 488 else 489 return build_delete (type, t, sfk_deleting_destructor, 490 LOOKUP_NORMAL, use_global_delete, 491 complain); 492 } 493 494 /* Report an error if the indicated template declaration is not the 495 sort of thing that should be a member template. */ 496 497 void 498 check_member_template (tree tmpl) 499 { 500 tree decl; 501 502 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL); 503 decl = DECL_TEMPLATE_RESULT (tmpl); 504 505 if (TREE_CODE (decl) == FUNCTION_DECL 506 || DECL_ALIAS_TEMPLATE_P (tmpl) 507 || (TREE_CODE (decl) == TYPE_DECL 508 && MAYBE_CLASS_TYPE_P (TREE_TYPE (decl)))) 509 { 510 /* The parser rejects template declarations in local classes. */ 511 gcc_assert (!current_function_decl); 512 /* The parser rejects any use of virtual in a function template. */ 513 gcc_assert (!(TREE_CODE (decl) == FUNCTION_DECL 514 && DECL_VIRTUAL_P (decl))); 515 516 /* The debug-information generating code doesn't know what to do 517 with member templates. */ 518 DECL_IGNORED_P (tmpl) = 1; 519 } 520 else 521 error ("template declaration of %q#D", decl); 522 } 523 524 /* Return true iff TYPE is a valid Java parameter or return type. */ 525 526 static bool 527 acceptable_java_type (tree type) 528 { 529 if (type == error_mark_node) 530 return false; 531 532 if (TREE_CODE (type) == VOID_TYPE || TYPE_FOR_JAVA (type)) 533 return true; 534 if (TREE_CODE (type) == POINTER_TYPE || TREE_CODE (type) == REFERENCE_TYPE) 535 { 536 type = TREE_TYPE (type); 537 if (TREE_CODE (type) == RECORD_TYPE) 538 { 539 tree args; int i; 540 if (! TYPE_FOR_JAVA (type)) 541 return false; 542 if (! CLASSTYPE_TEMPLATE_INFO (type)) 543 return true; 544 args = CLASSTYPE_TI_ARGS (type); 545 i = TREE_VEC_LENGTH (args); 546 while (--i >= 0) 547 { 548 type = TREE_VEC_ELT (args, i); 549 if (TREE_CODE (type) == POINTER_TYPE) 550 type = TREE_TYPE (type); 551 if (! TYPE_FOR_JAVA (type)) 552 return false; 553 } 554 return true; 555 } 556 } 557 return false; 558 } 559 560 /* For a METHOD in a Java class CTYPE, return true if 561 the parameter and return types are valid Java types. 562 Otherwise, print appropriate error messages, and return false. */ 563 564 bool 565 check_java_method (tree method) 566 { 567 bool jerr = false; 568 tree arg_types = TYPE_ARG_TYPES (TREE_TYPE (method)); 569 tree ret_type = TREE_TYPE (TREE_TYPE (method)); 570 571 if (!acceptable_java_type (ret_type)) 572 { 573 error ("Java method %qD has non-Java return type %qT", 574 method, ret_type); 575 jerr = true; 576 } 577 578 arg_types = TREE_CHAIN (arg_types); 579 if (DECL_HAS_IN_CHARGE_PARM_P (method)) 580 arg_types = TREE_CHAIN (arg_types); 581 if (DECL_HAS_VTT_PARM_P (method)) 582 arg_types = TREE_CHAIN (arg_types); 583 584 for (; arg_types != NULL_TREE; arg_types = TREE_CHAIN (arg_types)) 585 { 586 tree type = TREE_VALUE (arg_types); 587 if (!acceptable_java_type (type)) 588 { 589 if (type != error_mark_node) 590 error ("Java method %qD has non-Java parameter type %qT", 591 method, type); 592 jerr = true; 593 } 594 } 595 return !jerr; 596 } 597 598 /* Sanity check: report error if this function FUNCTION is not 599 really a member of the class (CTYPE) it is supposed to belong to. 600 TEMPLATE_PARMS is used to specify the template parameters of a member 601 template passed as FUNCTION_DECL. If the member template is passed as a 602 TEMPLATE_DECL, it can be NULL since the parameters can be extracted 603 from the declaration. If the function is not a function template, it 604 must be NULL. 605 It returns the original declaration for the function, NULL_TREE if 606 no declaration was found, error_mark_node if an error was emitted. */ 607 608 tree 609 check_classfn (tree ctype, tree function, tree template_parms) 610 { 611 int ix; 612 bool is_template; 613 tree pushed_scope; 614 615 if (DECL_USE_TEMPLATE (function) 616 && !(TREE_CODE (function) == TEMPLATE_DECL 617 && DECL_TEMPLATE_SPECIALIZATION (function)) 618 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (function))) 619 /* Since this is a specialization of a member template, 620 we're not going to find the declaration in the class. 621 For example, in: 622 623 struct S { template <typename T> void f(T); }; 624 template <> void S::f(int); 625 626 we're not going to find `S::f(int)', but there's no 627 reason we should, either. We let our callers know we didn't 628 find the method, but we don't complain. */ 629 return NULL_TREE; 630 631 /* Basic sanity check: for a template function, the template parameters 632 either were not passed, or they are the same of DECL_TEMPLATE_PARMS. */ 633 if (TREE_CODE (function) == TEMPLATE_DECL) 634 { 635 if (template_parms 636 && !comp_template_parms (template_parms, 637 DECL_TEMPLATE_PARMS (function))) 638 { 639 error ("template parameter lists provided don%'t match the " 640 "template parameters of %qD", function); 641 return error_mark_node; 642 } 643 template_parms = DECL_TEMPLATE_PARMS (function); 644 } 645 646 /* OK, is this a definition of a member template? */ 647 is_template = (template_parms != NULL_TREE); 648 649 /* We must enter the scope here, because conversion operators are 650 named by target type, and type equivalence relies on typenames 651 resolving within the scope of CTYPE. */ 652 pushed_scope = push_scope (ctype); 653 ix = class_method_index_for_fn (complete_type (ctype), function); 654 if (ix >= 0) 655 { 656 vec<tree, va_gc> *methods = CLASSTYPE_METHOD_VEC (ctype); 657 tree fndecls, fndecl = 0; 658 bool is_conv_op; 659 const char *format = NULL; 660 661 for (fndecls = (*methods)[ix]; 662 fndecls; fndecls = OVL_NEXT (fndecls)) 663 { 664 tree p1, p2; 665 666 fndecl = OVL_CURRENT (fndecls); 667 p1 = TYPE_ARG_TYPES (TREE_TYPE (function)); 668 p2 = TYPE_ARG_TYPES (TREE_TYPE (fndecl)); 669 670 /* We cannot simply call decls_match because this doesn't 671 work for static member functions that are pretending to 672 be methods, and because the name may have been changed by 673 asm("new_name"). */ 674 675 /* Get rid of the this parameter on functions that become 676 static. */ 677 if (DECL_STATIC_FUNCTION_P (fndecl) 678 && TREE_CODE (TREE_TYPE (function)) == METHOD_TYPE) 679 p1 = TREE_CHAIN (p1); 680 681 /* A member template definition only matches a member template 682 declaration. */ 683 if (is_template != (TREE_CODE (fndecl) == TEMPLATE_DECL)) 684 continue; 685 686 /* ref-qualifier or absence of same must match. */ 687 if (type_memfn_rqual (TREE_TYPE (function)) 688 != type_memfn_rqual (TREE_TYPE (fndecl))) 689 continue; 690 691 /* While finding a match, same types and params are not enough 692 if the function is versioned. Also check version ("target") 693 attributes. */ 694 if (same_type_p (TREE_TYPE (TREE_TYPE (function)), 695 TREE_TYPE (TREE_TYPE (fndecl))) 696 && compparms (p1, p2) 697 && !targetm.target_option.function_versions (function, fndecl) 698 && (!is_template 699 || comp_template_parms (template_parms, 700 DECL_TEMPLATE_PARMS (fndecl))) 701 && (DECL_TEMPLATE_SPECIALIZATION (function) 702 == DECL_TEMPLATE_SPECIALIZATION (fndecl)) 703 && (!DECL_TEMPLATE_SPECIALIZATION (function) 704 || (DECL_TI_TEMPLATE (function) 705 == DECL_TI_TEMPLATE (fndecl)))) 706 break; 707 } 708 if (fndecls) 709 { 710 if (pushed_scope) 711 pop_scope (pushed_scope); 712 return OVL_CURRENT (fndecls); 713 } 714 715 error_at (DECL_SOURCE_LOCATION (function), 716 "prototype for %q#D does not match any in class %qT", 717 function, ctype); 718 is_conv_op = DECL_CONV_FN_P (fndecl); 719 720 if (is_conv_op) 721 ix = CLASSTYPE_FIRST_CONVERSION_SLOT; 722 fndecls = (*methods)[ix]; 723 while (fndecls) 724 { 725 fndecl = OVL_CURRENT (fndecls); 726 fndecls = OVL_NEXT (fndecls); 727 728 if (!fndecls && is_conv_op) 729 { 730 if (methods->length () > (size_t) ++ix) 731 { 732 fndecls = (*methods)[ix]; 733 if (!DECL_CONV_FN_P (OVL_CURRENT (fndecls))) 734 { 735 fndecls = NULL_TREE; 736 is_conv_op = false; 737 } 738 } 739 else 740 is_conv_op = false; 741 } 742 if (format) 743 format = " %+#D"; 744 else if (fndecls) 745 format = N_("candidates are: %+#D"); 746 else 747 format = N_("candidate is: %+#D"); 748 error (format, fndecl); 749 } 750 } 751 else if (!COMPLETE_TYPE_P (ctype)) 752 cxx_incomplete_type_error (function, ctype); 753 else 754 error ("no %q#D member function declared in class %qT", 755 function, ctype); 756 757 if (pushed_scope) 758 pop_scope (pushed_scope); 759 return error_mark_node; 760 } 761 762 /* DECL is a function with vague linkage. Remember it so that at the 763 end of the translation unit we can decide whether or not to emit 764 it. */ 765 766 void 767 note_vague_linkage_fn (tree decl) 768 { 769 DECL_DEFER_OUTPUT (decl) = 1; 770 vec_safe_push (deferred_fns, decl); 771 } 772 773 /* We have just processed the DECL, which is a static data member. 774 The other parameters are as for cp_finish_decl. */ 775 776 void 777 finish_static_data_member_decl (tree decl, 778 tree init, bool init_const_expr_p, 779 tree asmspec_tree, 780 int flags) 781 { 782 DECL_CONTEXT (decl) = current_class_type; 783 784 /* We cannot call pushdecl here, because that would fill in the 785 TREE_CHAIN of our decl. Instead, we modify cp_finish_decl to do 786 the right thing, namely, to put this decl out straight away. */ 787 788 if (! processing_template_decl) 789 vec_safe_push (pending_statics, decl); 790 791 if (LOCAL_CLASS_P (current_class_type) 792 /* We already complained about the template definition. */ 793 && !DECL_TEMPLATE_INSTANTIATION (decl)) 794 permerror (input_location, "local class %q#T shall not have static data member %q#D", 795 current_class_type, decl); 796 797 DECL_IN_AGGR_P (decl) = 1; 798 799 if (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE 800 && TYPE_DOMAIN (TREE_TYPE (decl)) == NULL_TREE) 801 SET_VAR_HAD_UNKNOWN_BOUND (decl); 802 803 cp_finish_decl (decl, init, init_const_expr_p, asmspec_tree, flags); 804 } 805 806 /* DECLARATOR and DECLSPECS correspond to a class member. The other 807 parameters are as for cp_finish_decl. Return the DECL for the 808 class member declared. */ 809 810 tree 811 grokfield (const cp_declarator *declarator, 812 cp_decl_specifier_seq *declspecs, 813 tree init, bool init_const_expr_p, 814 tree asmspec_tree, 815 tree attrlist) 816 { 817 tree value; 818 const char *asmspec = 0; 819 int flags; 820 tree name; 821 822 if (init 823 && TREE_CODE (init) == TREE_LIST 824 && TREE_VALUE (init) == error_mark_node 825 && TREE_CHAIN (init) == NULL_TREE) 826 init = NULL_TREE; 827 828 value = grokdeclarator (declarator, declspecs, FIELD, init != 0, &attrlist); 829 if (! value || error_operand_p (value)) 830 /* friend or constructor went bad. */ 831 return error_mark_node; 832 833 if (TREE_CODE (value) == TYPE_DECL && init) 834 { 835 error ("typedef %qD is initialized (use decltype instead)", value); 836 init = NULL_TREE; 837 } 838 839 /* Pass friendly classes back. */ 840 if (value == void_type_node) 841 return value; 842 843 /* Pass friend decls back. */ 844 if ((TREE_CODE (value) == FUNCTION_DECL 845 || TREE_CODE (value) == TEMPLATE_DECL) 846 && DECL_CONTEXT (value) != current_class_type) 847 return value; 848 849 name = DECL_NAME (value); 850 851 if (name != NULL_TREE) 852 { 853 if (TREE_CODE (name) == TEMPLATE_ID_EXPR) 854 { 855 error ("explicit template argument list not allowed"); 856 return error_mark_node; 857 } 858 859 if (IDENTIFIER_POINTER (name)[0] == '_' 860 && ! strcmp (IDENTIFIER_POINTER (name), "_vptr")) 861 error ("member %qD conflicts with virtual function table field name", 862 value); 863 } 864 865 /* Stash away type declarations. */ 866 if (TREE_CODE (value) == TYPE_DECL) 867 { 868 DECL_NONLOCAL (value) = 1; 869 DECL_CONTEXT (value) = current_class_type; 870 871 if (attrlist) 872 { 873 int attrflags = 0; 874 875 /* If this is a typedef that names the class for linkage purposes 876 (7.1.3p8), apply any attributes directly to the type. */ 877 if (TAGGED_TYPE_P (TREE_TYPE (value)) 878 && value == TYPE_NAME (TYPE_MAIN_VARIANT (TREE_TYPE (value)))) 879 attrflags = ATTR_FLAG_TYPE_IN_PLACE; 880 881 cplus_decl_attributes (&value, attrlist, attrflags); 882 } 883 884 if (decl_spec_seq_has_spec_p (declspecs, ds_typedef) 885 && TREE_TYPE (value) != error_mark_node 886 && TYPE_NAME (TYPE_MAIN_VARIANT (TREE_TYPE (value))) != value) 887 set_underlying_type (value); 888 889 /* It's important that push_template_decl below follows 890 set_underlying_type above so that the created template 891 carries the properly set type of VALUE. */ 892 if (processing_template_decl) 893 value = push_template_decl (value); 894 895 record_locally_defined_typedef (value); 896 return value; 897 } 898 899 if (DECL_IN_AGGR_P (value)) 900 { 901 error ("%qD is already defined in %qT", value, DECL_CONTEXT (value)); 902 return void_type_node; 903 } 904 905 if (asmspec_tree && asmspec_tree != error_mark_node) 906 asmspec = TREE_STRING_POINTER (asmspec_tree); 907 908 if (init) 909 { 910 if (TREE_CODE (value) == FUNCTION_DECL) 911 { 912 /* Initializers for functions are rejected early in the parser. 913 If we get here, it must be a pure specifier for a method. */ 914 if (init == ridpointers[(int)RID_DELETE]) 915 { 916 DECL_DELETED_FN (value) = 1; 917 DECL_DECLARED_INLINE_P (value) = 1; 918 DECL_INITIAL (value) = error_mark_node; 919 } 920 else if (init == ridpointers[(int)RID_DEFAULT]) 921 { 922 if (defaultable_fn_check (value)) 923 { 924 DECL_DEFAULTED_FN (value) = 1; 925 DECL_INITIALIZED_IN_CLASS_P (value) = 1; 926 DECL_DECLARED_INLINE_P (value) = 1; 927 } 928 } 929 else if (TREE_CODE (init) == DEFAULT_ARG) 930 error ("invalid initializer for member function %qD", value); 931 else if (TREE_CODE (TREE_TYPE (value)) == METHOD_TYPE) 932 { 933 if (integer_zerop (init)) 934 DECL_PURE_VIRTUAL_P (value) = 1; 935 else if (error_operand_p (init)) 936 ; /* An error has already been reported. */ 937 else 938 error ("invalid initializer for member function %qD", 939 value); 940 } 941 else 942 { 943 gcc_assert (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE); 944 error ("initializer specified for static member function %qD", 945 value); 946 } 947 } 948 else if (TREE_CODE (value) == FIELD_DECL) 949 /* C++11 NSDMI, keep going. */; 950 else if (TREE_CODE (value) != VAR_DECL) 951 gcc_unreachable (); 952 else if (!processing_template_decl) 953 { 954 if (TREE_CODE (init) == CONSTRUCTOR) 955 init = digest_init (TREE_TYPE (value), init, tf_warning_or_error); 956 init = maybe_constant_init (init); 957 958 if (init != error_mark_node && !TREE_CONSTANT (init)) 959 { 960 /* We can allow references to things that are effectively 961 static, since references are initialized with the 962 address. */ 963 if (TREE_CODE (TREE_TYPE (value)) != REFERENCE_TYPE 964 || (TREE_STATIC (init) == 0 965 && (!DECL_P (init) || DECL_EXTERNAL (init) == 0))) 966 { 967 error ("field initializer is not constant"); 968 init = error_mark_node; 969 } 970 } 971 } 972 } 973 974 if (processing_template_decl 975 && (TREE_CODE (value) == VAR_DECL || TREE_CODE (value) == FUNCTION_DECL)) 976 { 977 value = push_template_decl (value); 978 if (error_operand_p (value)) 979 return error_mark_node; 980 } 981 982 if (attrlist) 983 cplus_decl_attributes (&value, attrlist, 0); 984 985 if (init && BRACE_ENCLOSED_INITIALIZER_P (init) 986 && CONSTRUCTOR_IS_DIRECT_INIT (init)) 987 flags = LOOKUP_NORMAL; 988 else 989 flags = LOOKUP_IMPLICIT; 990 991 switch (TREE_CODE (value)) 992 { 993 case VAR_DECL: 994 finish_static_data_member_decl (value, init, init_const_expr_p, 995 asmspec_tree, flags); 996 return value; 997 998 case FIELD_DECL: 999 if (asmspec) 1000 error ("%<asm%> specifiers are not permitted on non-static data members"); 1001 if (DECL_INITIAL (value) == error_mark_node) 1002 init = error_mark_node; 1003 cp_finish_decl (value, init, /*init_const_expr_p=*/false, 1004 NULL_TREE, flags); 1005 DECL_IN_AGGR_P (value) = 1; 1006 return value; 1007 1008 case FUNCTION_DECL: 1009 if (asmspec) 1010 set_user_assembler_name (value, asmspec); 1011 1012 cp_finish_decl (value, 1013 /*init=*/NULL_TREE, 1014 /*init_const_expr_p=*/false, 1015 asmspec_tree, flags); 1016 1017 /* Pass friends back this way. */ 1018 if (DECL_FRIEND_P (value)) 1019 return void_type_node; 1020 1021 DECL_IN_AGGR_P (value) = 1; 1022 return value; 1023 1024 default: 1025 gcc_unreachable (); 1026 } 1027 return NULL_TREE; 1028 } 1029 1030 /* Like `grokfield', but for bitfields. 1031 WIDTH is non-NULL for bit fields only, and is an INTEGER_CST node. */ 1032 1033 tree 1034 grokbitfield (const cp_declarator *declarator, 1035 cp_decl_specifier_seq *declspecs, tree width, 1036 tree attrlist) 1037 { 1038 tree value = grokdeclarator (declarator, declspecs, BITFIELD, 0, &attrlist); 1039 1040 if (value == error_mark_node) 1041 return NULL_TREE; /* friends went bad. */ 1042 1043 /* Pass friendly classes back. */ 1044 if (TREE_CODE (value) == VOID_TYPE) 1045 return void_type_node; 1046 1047 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (value)) 1048 && (POINTER_TYPE_P (value) 1049 || !dependent_type_p (TREE_TYPE (value)))) 1050 { 1051 error ("bit-field %qD with non-integral type", value); 1052 return error_mark_node; 1053 } 1054 1055 if (TREE_CODE (value) == TYPE_DECL) 1056 { 1057 error ("cannot declare %qD to be a bit-field type", value); 1058 return NULL_TREE; 1059 } 1060 1061 /* Usually, finish_struct_1 catches bitfields with invalid types. 1062 But, in the case of bitfields with function type, we confuse 1063 ourselves into thinking they are member functions, so we must 1064 check here. */ 1065 if (TREE_CODE (value) == FUNCTION_DECL) 1066 { 1067 error ("cannot declare bit-field %qD with function type", 1068 DECL_NAME (value)); 1069 return NULL_TREE; 1070 } 1071 1072 if (DECL_IN_AGGR_P (value)) 1073 { 1074 error ("%qD is already defined in the class %qT", value, 1075 DECL_CONTEXT (value)); 1076 return void_type_node; 1077 } 1078 1079 if (TREE_STATIC (value)) 1080 { 1081 error ("static member %qD cannot be a bit-field", value); 1082 return NULL_TREE; 1083 } 1084 cp_finish_decl (value, NULL_TREE, false, NULL_TREE, 0); 1085 1086 if (width != error_mark_node) 1087 { 1088 /* The width must be an integer type. */ 1089 if (!type_dependent_expression_p (width) 1090 && !INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (width))) 1091 error ("width of bit-field %qD has non-integral type %qT", value, 1092 TREE_TYPE (width)); 1093 DECL_INITIAL (value) = width; 1094 SET_DECL_C_BIT_FIELD (value); 1095 } 1096 1097 DECL_IN_AGGR_P (value) = 1; 1098 1099 if (attrlist) 1100 cplus_decl_attributes (&value, attrlist, /*flags=*/0); 1101 1102 return value; 1103 } 1104 1105 1106 /* Returns true iff ATTR is an attribute which needs to be applied at 1107 instantiation time rather than template definition time. */ 1108 1109 static bool 1110 is_late_template_attribute (tree attr, tree decl) 1111 { 1112 tree name = get_attribute_name (attr); 1113 tree args = TREE_VALUE (attr); 1114 const struct attribute_spec *spec = lookup_attribute_spec (name); 1115 tree arg; 1116 1117 if (!spec) 1118 /* Unknown attribute. */ 1119 return false; 1120 1121 /* Attribute weak handling wants to write out assembly right away. */ 1122 if (is_attribute_p ("weak", name)) 1123 return true; 1124 1125 /* Attribute unused is applied directly, as it appertains to 1126 decls. */ 1127 if (is_attribute_p ("unused", name)) 1128 return false; 1129 1130 /* If any of the arguments are dependent expressions, we can't evaluate 1131 the attribute until instantiation time. */ 1132 for (arg = args; arg; arg = TREE_CHAIN (arg)) 1133 { 1134 tree t = TREE_VALUE (arg); 1135 1136 /* If the first attribute argument is an identifier, only consider 1137 second and following arguments. Attributes like mode, format, 1138 cleanup and several target specific attributes aren't late 1139 just because they have an IDENTIFIER_NODE as first argument. */ 1140 if (arg == args && TREE_CODE (t) == IDENTIFIER_NODE) 1141 continue; 1142 1143 if (value_dependent_expression_p (t) 1144 || type_dependent_expression_p (t)) 1145 return true; 1146 } 1147 1148 if (TREE_CODE (decl) == TYPE_DECL 1149 || TYPE_P (decl) 1150 || spec->type_required) 1151 { 1152 tree type = TYPE_P (decl) ? decl : TREE_TYPE (decl); 1153 1154 /* We can't apply any attributes to a completely unknown type until 1155 instantiation time. */ 1156 enum tree_code code = TREE_CODE (type); 1157 if (code == TEMPLATE_TYPE_PARM 1158 || code == BOUND_TEMPLATE_TEMPLATE_PARM 1159 || code == TYPENAME_TYPE) 1160 return true; 1161 /* Also defer most attributes on dependent types. This is not 1162 necessary in all cases, but is the better default. */ 1163 else if (dependent_type_p (type) 1164 /* But attribute visibility specifically works on 1165 templates. */ 1166 && !is_attribute_p ("visibility", name)) 1167 return true; 1168 else 1169 return false; 1170 } 1171 else 1172 return false; 1173 } 1174 1175 /* ATTR_P is a list of attributes. Remove any attributes which need to be 1176 applied at instantiation time and return them. If IS_DEPENDENT is true, 1177 the declaration itself is dependent, so all attributes should be applied 1178 at instantiation time. */ 1179 1180 static tree 1181 splice_template_attributes (tree *attr_p, tree decl) 1182 { 1183 tree *p = attr_p; 1184 tree late_attrs = NULL_TREE; 1185 tree *q = &late_attrs; 1186 1187 if (!p) 1188 return NULL_TREE; 1189 1190 for (; *p; ) 1191 { 1192 if (is_late_template_attribute (*p, decl)) 1193 { 1194 ATTR_IS_DEPENDENT (*p) = 1; 1195 *q = *p; 1196 *p = TREE_CHAIN (*p); 1197 q = &TREE_CHAIN (*q); 1198 *q = NULL_TREE; 1199 } 1200 else 1201 p = &TREE_CHAIN (*p); 1202 } 1203 1204 return late_attrs; 1205 } 1206 1207 /* Remove any late attributes from the list in ATTR_P and attach them to 1208 DECL_P. */ 1209 1210 static void 1211 save_template_attributes (tree *attr_p, tree *decl_p) 1212 { 1213 tree late_attrs = splice_template_attributes (attr_p, *decl_p); 1214 tree *q; 1215 tree old_attrs = NULL_TREE; 1216 1217 if (!late_attrs) 1218 return; 1219 1220 if (DECL_P (*decl_p)) 1221 q = &DECL_ATTRIBUTES (*decl_p); 1222 else 1223 q = &TYPE_ATTRIBUTES (*decl_p); 1224 1225 old_attrs = *q; 1226 1227 /* Merge the late attributes at the beginning with the attribute 1228 list. */ 1229 late_attrs = merge_attributes (late_attrs, *q); 1230 *q = late_attrs; 1231 1232 if (!DECL_P (*decl_p) && *decl_p == TYPE_MAIN_VARIANT (*decl_p)) 1233 { 1234 /* We've added new attributes directly to the main variant, so 1235 now we need to update all of the other variants to include 1236 these new attributes. */ 1237 tree variant; 1238 for (variant = TYPE_NEXT_VARIANT (*decl_p); variant; 1239 variant = TYPE_NEXT_VARIANT (variant)) 1240 { 1241 gcc_assert (TYPE_ATTRIBUTES (variant) == old_attrs); 1242 TYPE_ATTRIBUTES (variant) = TYPE_ATTRIBUTES (*decl_p); 1243 } 1244 } 1245 } 1246 1247 /* Like reconstruct_complex_type, but handle also template trees. */ 1248 1249 tree 1250 cp_reconstruct_complex_type (tree type, tree bottom) 1251 { 1252 tree inner, outer; 1253 1254 if (TREE_CODE (type) == POINTER_TYPE) 1255 { 1256 inner = cp_reconstruct_complex_type (TREE_TYPE (type), bottom); 1257 outer = build_pointer_type_for_mode (inner, TYPE_MODE (type), 1258 TYPE_REF_CAN_ALIAS_ALL (type)); 1259 } 1260 else if (TREE_CODE (type) == REFERENCE_TYPE) 1261 { 1262 inner = cp_reconstruct_complex_type (TREE_TYPE (type), bottom); 1263 outer = build_reference_type_for_mode (inner, TYPE_MODE (type), 1264 TYPE_REF_CAN_ALIAS_ALL (type)); 1265 } 1266 else if (TREE_CODE (type) == ARRAY_TYPE) 1267 { 1268 inner = cp_reconstruct_complex_type (TREE_TYPE (type), bottom); 1269 outer = build_cplus_array_type (inner, TYPE_DOMAIN (type)); 1270 /* Don't call cp_build_qualified_type on ARRAY_TYPEs, the 1271 element type qualification will be handled by the recursive 1272 cp_reconstruct_complex_type call and cp_build_qualified_type 1273 for ARRAY_TYPEs changes the element type. */ 1274 return outer; 1275 } 1276 else if (TREE_CODE (type) == FUNCTION_TYPE) 1277 { 1278 inner = cp_reconstruct_complex_type (TREE_TYPE (type), bottom); 1279 outer = build_function_type (inner, TYPE_ARG_TYPES (type)); 1280 outer = apply_memfn_quals (outer, 1281 type_memfn_quals (type), 1282 type_memfn_rqual (type)); 1283 } 1284 else if (TREE_CODE (type) == METHOD_TYPE) 1285 { 1286 inner = cp_reconstruct_complex_type (TREE_TYPE (type), bottom); 1287 /* The build_method_type_directly() routine prepends 'this' to argument list, 1288 so we must compensate by getting rid of it. */ 1289 outer 1290 = build_method_type_directly 1291 (class_of_this_parm (type), inner, 1292 TREE_CHAIN (TYPE_ARG_TYPES (type))); 1293 } 1294 else if (TREE_CODE (type) == OFFSET_TYPE) 1295 { 1296 inner = cp_reconstruct_complex_type (TREE_TYPE (type), bottom); 1297 outer = build_offset_type (TYPE_OFFSET_BASETYPE (type), inner); 1298 } 1299 else 1300 return bottom; 1301 1302 if (TYPE_ATTRIBUTES (type)) 1303 outer = cp_build_type_attribute_variant (outer, TYPE_ATTRIBUTES (type)); 1304 return cp_build_qualified_type (outer, cp_type_quals (type)); 1305 } 1306 1307 /* Replaces any constexpr expression that may be into the attributes 1308 arguments with their reduced value. */ 1309 1310 static void 1311 cp_check_const_attributes (tree attributes) 1312 { 1313 tree attr; 1314 for (attr = attributes; attr; attr = TREE_CHAIN (attr)) 1315 { 1316 tree arg; 1317 for (arg = TREE_VALUE (attr); arg; arg = TREE_CHAIN (arg)) 1318 { 1319 tree expr = TREE_VALUE (arg); 1320 if (EXPR_P (expr)) 1321 TREE_VALUE (arg) = maybe_constant_value (expr); 1322 } 1323 } 1324 } 1325 1326 /* Like decl_attributes, but handle C++ complexity. */ 1327 1328 void 1329 cplus_decl_attributes (tree *decl, tree attributes, int flags) 1330 { 1331 if (*decl == NULL_TREE || *decl == void_type_node 1332 || *decl == error_mark_node) 1333 return; 1334 1335 if (processing_template_decl) 1336 { 1337 if (check_for_bare_parameter_packs (attributes)) 1338 return; 1339 1340 save_template_attributes (&attributes, decl); 1341 } 1342 1343 cp_check_const_attributes (attributes); 1344 1345 if (TREE_CODE (*decl) == TEMPLATE_DECL) 1346 decl = &DECL_TEMPLATE_RESULT (*decl); 1347 1348 decl_attributes (decl, attributes, flags); 1349 1350 if (TREE_CODE (*decl) == TYPE_DECL) 1351 SET_IDENTIFIER_TYPE_VALUE (DECL_NAME (*decl), TREE_TYPE (*decl)); 1352 } 1353 1354 /* Walks through the namespace- or function-scope anonymous union 1355 OBJECT, with the indicated TYPE, building appropriate VAR_DECLs. 1356 Returns one of the fields for use in the mangled name. */ 1357 1358 static tree 1359 build_anon_union_vars (tree type, tree object) 1360 { 1361 tree main_decl = NULL_TREE; 1362 tree field; 1363 1364 /* Rather than write the code to handle the non-union case, 1365 just give an error. */ 1366 if (TREE_CODE (type) != UNION_TYPE) 1367 { 1368 error ("anonymous struct not inside named type"); 1369 return error_mark_node; 1370 } 1371 1372 for (field = TYPE_FIELDS (type); 1373 field != NULL_TREE; 1374 field = DECL_CHAIN (field)) 1375 { 1376 tree decl; 1377 tree ref; 1378 1379 if (DECL_ARTIFICIAL (field)) 1380 continue; 1381 if (TREE_CODE (field) != FIELD_DECL) 1382 { 1383 permerror (input_location, "%q+#D invalid; an anonymous union can only " 1384 "have non-static data members", field); 1385 continue; 1386 } 1387 1388 if (TREE_PRIVATE (field)) 1389 permerror (input_location, "private member %q+#D in anonymous union", field); 1390 else if (TREE_PROTECTED (field)) 1391 permerror (input_location, "protected member %q+#D in anonymous union", field); 1392 1393 if (processing_template_decl) 1394 ref = build_min_nt_loc (UNKNOWN_LOCATION, COMPONENT_REF, object, 1395 DECL_NAME (field), NULL_TREE); 1396 else 1397 ref = build_class_member_access_expr (object, field, NULL_TREE, 1398 false, tf_warning_or_error); 1399 1400 if (DECL_NAME (field)) 1401 { 1402 tree base; 1403 1404 decl = build_decl (input_location, 1405 VAR_DECL, DECL_NAME (field), TREE_TYPE (field)); 1406 DECL_ANON_UNION_VAR_P (decl) = 1; 1407 DECL_ARTIFICIAL (decl) = 1; 1408 1409 base = get_base_address (object); 1410 TREE_PUBLIC (decl) = TREE_PUBLIC (base); 1411 TREE_STATIC (decl) = TREE_STATIC (base); 1412 DECL_EXTERNAL (decl) = DECL_EXTERNAL (base); 1413 1414 SET_DECL_VALUE_EXPR (decl, ref); 1415 DECL_HAS_VALUE_EXPR_P (decl) = 1; 1416 1417 decl = pushdecl (decl); 1418 } 1419 else if (ANON_AGGR_TYPE_P (TREE_TYPE (field))) 1420 decl = build_anon_union_vars (TREE_TYPE (field), ref); 1421 else 1422 decl = 0; 1423 1424 if (main_decl == NULL_TREE) 1425 main_decl = decl; 1426 } 1427 1428 return main_decl; 1429 } 1430 1431 /* Finish off the processing of a UNION_TYPE structure. If the union is an 1432 anonymous union, then all members must be laid out together. PUBLIC_P 1433 is nonzero if this union is not declared static. */ 1434 1435 void 1436 finish_anon_union (tree anon_union_decl) 1437 { 1438 tree type; 1439 tree main_decl; 1440 bool public_p; 1441 1442 if (anon_union_decl == error_mark_node) 1443 return; 1444 1445 type = TREE_TYPE (anon_union_decl); 1446 public_p = TREE_PUBLIC (anon_union_decl); 1447 1448 /* The VAR_DECL's context is the same as the TYPE's context. */ 1449 DECL_CONTEXT (anon_union_decl) = DECL_CONTEXT (TYPE_NAME (type)); 1450 1451 if (TYPE_FIELDS (type) == NULL_TREE) 1452 return; 1453 1454 if (public_p) 1455 { 1456 error ("namespace-scope anonymous aggregates must be static"); 1457 return; 1458 } 1459 1460 main_decl = build_anon_union_vars (type, anon_union_decl); 1461 if (main_decl == error_mark_node) 1462 return; 1463 if (main_decl == NULL_TREE) 1464 { 1465 warning (0, "anonymous union with no members"); 1466 return; 1467 } 1468 1469 if (!processing_template_decl) 1470 { 1471 /* Use main_decl to set the mangled name. */ 1472 DECL_NAME (anon_union_decl) = DECL_NAME (main_decl); 1473 maybe_commonize_var (anon_union_decl); 1474 if (TREE_STATIC (anon_union_decl) || DECL_EXTERNAL (anon_union_decl)) 1475 mangle_decl (anon_union_decl); 1476 DECL_NAME (anon_union_decl) = NULL_TREE; 1477 } 1478 1479 pushdecl (anon_union_decl); 1480 cp_finish_decl (anon_union_decl, NULL_TREE, false, NULL_TREE, 0); 1481 } 1482 1483 /* Auxiliary functions to make type signatures for 1484 `operator new' and `operator delete' correspond to 1485 what compiler will be expecting. */ 1486 1487 tree 1488 coerce_new_type (tree type) 1489 { 1490 int e = 0; 1491 tree args = TYPE_ARG_TYPES (type); 1492 1493 gcc_assert (TREE_CODE (type) == FUNCTION_TYPE); 1494 1495 if (!same_type_p (TREE_TYPE (type), ptr_type_node)) 1496 { 1497 e = 1; 1498 error ("%<operator new%> must return type %qT", ptr_type_node); 1499 } 1500 1501 if (args && args != void_list_node) 1502 { 1503 if (TREE_PURPOSE (args)) 1504 { 1505 /* [basic.stc.dynamic.allocation] 1506 1507 The first parameter shall not have an associated default 1508 argument. */ 1509 error ("the first parameter of %<operator new%> cannot " 1510 "have a default argument"); 1511 /* Throw away the default argument. */ 1512 TREE_PURPOSE (args) = NULL_TREE; 1513 } 1514 1515 if (!same_type_p (TREE_VALUE (args), size_type_node)) 1516 { 1517 e = 2; 1518 args = TREE_CHAIN (args); 1519 } 1520 } 1521 else 1522 e = 2; 1523 1524 if (e == 2) 1525 permerror (input_location, "%<operator new%> takes type %<size_t%> (%qT) " 1526 "as first parameter", size_type_node); 1527 1528 switch (e) 1529 { 1530 case 2: 1531 args = tree_cons (NULL_TREE, size_type_node, args); 1532 /* Fall through. */ 1533 case 1: 1534 type = build_exception_variant 1535 (build_function_type (ptr_type_node, args), 1536 TYPE_RAISES_EXCEPTIONS (type)); 1537 /* Fall through. */ 1538 default:; 1539 } 1540 return type; 1541 } 1542 1543 tree 1544 coerce_delete_type (tree type) 1545 { 1546 int e = 0; 1547 tree args = TYPE_ARG_TYPES (type); 1548 1549 gcc_assert (TREE_CODE (type) == FUNCTION_TYPE); 1550 1551 if (!same_type_p (TREE_TYPE (type), void_type_node)) 1552 { 1553 e = 1; 1554 error ("%<operator delete%> must return type %qT", void_type_node); 1555 } 1556 1557 if (!args || args == void_list_node 1558 || !same_type_p (TREE_VALUE (args), ptr_type_node)) 1559 { 1560 e = 2; 1561 if (args && args != void_list_node) 1562 args = TREE_CHAIN (args); 1563 error ("%<operator delete%> takes type %qT as first parameter", 1564 ptr_type_node); 1565 } 1566 switch (e) 1567 { 1568 case 2: 1569 args = tree_cons (NULL_TREE, ptr_type_node, args); 1570 /* Fall through. */ 1571 case 1: 1572 type = build_exception_variant 1573 (build_function_type (void_type_node, args), 1574 TYPE_RAISES_EXCEPTIONS (type)); 1575 /* Fall through. */ 1576 default:; 1577 } 1578 1579 return type; 1580 } 1581 1582 /* DECL is a VAR_DECL for a vtable: walk through the entries in the vtable 1583 and mark them as needed. */ 1584 1585 static void 1586 mark_vtable_entries (tree decl) 1587 { 1588 tree fnaddr; 1589 unsigned HOST_WIDE_INT idx; 1590 1591 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (DECL_INITIAL (decl)), 1592 idx, fnaddr) 1593 { 1594 tree fn; 1595 1596 STRIP_NOPS (fnaddr); 1597 1598 if (TREE_CODE (fnaddr) != ADDR_EXPR 1599 && TREE_CODE (fnaddr) != FDESC_EXPR) 1600 /* This entry is an offset: a virtual base class offset, a 1601 virtual call offset, an RTTI offset, etc. */ 1602 continue; 1603 1604 fn = TREE_OPERAND (fnaddr, 0); 1605 TREE_ADDRESSABLE (fn) = 1; 1606 /* When we don't have vcall offsets, we output thunks whenever 1607 we output the vtables that contain them. With vcall offsets, 1608 we know all the thunks we'll need when we emit a virtual 1609 function, so we emit the thunks there instead. */ 1610 if (DECL_THUNK_P (fn)) 1611 use_thunk (fn, /*emit_p=*/0); 1612 mark_used (fn); 1613 } 1614 } 1615 1616 /* Set DECL up to have the closest approximation of "initialized common" 1617 linkage available. */ 1618 1619 void 1620 comdat_linkage (tree decl) 1621 { 1622 if (flag_weak) 1623 make_decl_one_only (decl, cxx_comdat_group (decl)); 1624 else if (TREE_CODE (decl) == FUNCTION_DECL 1625 || (TREE_CODE (decl) == VAR_DECL && DECL_ARTIFICIAL (decl))) 1626 /* We can just emit function and compiler-generated variables 1627 statically; having multiple copies is (for the most part) only 1628 a waste of space. 1629 1630 There are two correctness issues, however: the address of a 1631 template instantiation with external linkage should be the 1632 same, independent of what translation unit asks for the 1633 address, and this will not hold when we emit multiple copies of 1634 the function. However, there's little else we can do. 1635 1636 Also, by default, the typeinfo implementation assumes that 1637 there will be only one copy of the string used as the name for 1638 each type. Therefore, if weak symbols are unavailable, the 1639 run-time library should perform a more conservative check; it 1640 should perform a string comparison, rather than an address 1641 comparison. */ 1642 TREE_PUBLIC (decl) = 0; 1643 else 1644 { 1645 /* Static data member template instantiations, however, cannot 1646 have multiple copies. */ 1647 if (DECL_INITIAL (decl) == 0 1648 || DECL_INITIAL (decl) == error_mark_node) 1649 DECL_COMMON (decl) = 1; 1650 else if (EMPTY_CONSTRUCTOR_P (DECL_INITIAL (decl))) 1651 { 1652 DECL_COMMON (decl) = 1; 1653 DECL_INITIAL (decl) = error_mark_node; 1654 } 1655 else if (!DECL_EXPLICIT_INSTANTIATION (decl)) 1656 { 1657 /* We can't do anything useful; leave vars for explicit 1658 instantiation. */ 1659 DECL_EXTERNAL (decl) = 1; 1660 DECL_NOT_REALLY_EXTERN (decl) = 0; 1661 } 1662 } 1663 1664 DECL_COMDAT (decl) = 1; 1665 } 1666 1667 /* For win32 we also want to put explicit instantiations in 1668 linkonce sections, so that they will be merged with implicit 1669 instantiations; otherwise we get duplicate symbol errors. 1670 For Darwin we do not want explicit instantiations to be 1671 linkonce. */ 1672 1673 void 1674 maybe_make_one_only (tree decl) 1675 { 1676 /* We used to say that this was not necessary on targets that support weak 1677 symbols, because the implicit instantiations will defer to the explicit 1678 one. However, that's not actually the case in SVR4; a strong definition 1679 after a weak one is an error. Also, not making explicit 1680 instantiations one_only means that we can end up with two copies of 1681 some template instantiations. */ 1682 if (! flag_weak) 1683 return; 1684 1685 /* We can't set DECL_COMDAT on functions, or cp_finish_file will think 1686 we can get away with not emitting them if they aren't used. We need 1687 to for variables so that cp_finish_decl will update their linkage, 1688 because their DECL_INITIAL may not have been set properly yet. */ 1689 1690 if (!TARGET_WEAK_NOT_IN_ARCHIVE_TOC 1691 || (! DECL_EXPLICIT_INSTANTIATION (decl) 1692 && ! DECL_TEMPLATE_SPECIALIZATION (decl))) 1693 { 1694 make_decl_one_only (decl, cxx_comdat_group (decl)); 1695 1696 if (TREE_CODE (decl) == VAR_DECL) 1697 { 1698 DECL_COMDAT (decl) = 1; 1699 /* Mark it needed so we don't forget to emit it. */ 1700 mark_decl_referenced (decl); 1701 TREE_USED (decl) = 1; 1702 } 1703 } 1704 } 1705 1706 /* Returns true iff DECL, a FUNCTION_DECL or VAR_DECL, has vague linkage. 1707 This predicate will give the right answer during parsing of the 1708 function, which other tests may not. */ 1709 1710 bool 1711 vague_linkage_p (tree decl) 1712 { 1713 /* Unfortunately, import_export_decl has not always been called 1714 before the function is processed, so we cannot simply check 1715 DECL_COMDAT. */ 1716 return (DECL_COMDAT (decl) 1717 || (((TREE_CODE (decl) == FUNCTION_DECL 1718 && DECL_DECLARED_INLINE_P (decl)) 1719 || (DECL_LANG_SPECIFIC (decl) 1720 && DECL_TEMPLATE_INSTANTIATION (decl))) 1721 && TREE_PUBLIC (decl))); 1722 } 1723 1724 /* Determine whether or not we want to specifically import or export CTYPE, 1725 using various heuristics. */ 1726 1727 static void 1728 import_export_class (tree ctype) 1729 { 1730 /* -1 for imported, 1 for exported. */ 1731 int import_export = 0; 1732 1733 /* It only makes sense to call this function at EOF. The reason is 1734 that this function looks at whether or not the first non-inline 1735 non-abstract virtual member function has been defined in this 1736 translation unit. But, we can't possibly know that until we've 1737 seen the entire translation unit. */ 1738 gcc_assert (at_eof); 1739 1740 if (CLASSTYPE_INTERFACE_KNOWN (ctype)) 1741 return; 1742 1743 /* If MULTIPLE_SYMBOL_SPACES is set and we saw a #pragma interface, 1744 we will have CLASSTYPE_INTERFACE_ONLY set but not 1745 CLASSTYPE_INTERFACE_KNOWN. In that case, we don't want to use this 1746 heuristic because someone will supply a #pragma implementation 1747 elsewhere, and deducing it here would produce a conflict. */ 1748 if (CLASSTYPE_INTERFACE_ONLY (ctype)) 1749 return; 1750 1751 if (lookup_attribute ("dllimport", TYPE_ATTRIBUTES (ctype))) 1752 import_export = -1; 1753 else if (lookup_attribute ("dllexport", TYPE_ATTRIBUTES (ctype))) 1754 import_export = 1; 1755 else if (CLASSTYPE_IMPLICIT_INSTANTIATION (ctype) 1756 && !flag_implicit_templates) 1757 /* For a template class, without -fimplicit-templates, check the 1758 repository. If the virtual table is assigned to this 1759 translation unit, then export the class; otherwise, import 1760 it. */ 1761 import_export = repo_export_class_p (ctype) ? 1 : -1; 1762 else if (TYPE_POLYMORPHIC_P (ctype)) 1763 { 1764 /* The ABI specifies that the virtual table and associated 1765 information are emitted with the key method, if any. */ 1766 tree method = CLASSTYPE_KEY_METHOD (ctype); 1767 /* If weak symbol support is not available, then we must be 1768 careful not to emit the vtable when the key function is 1769 inline. An inline function can be defined in multiple 1770 translation units. If we were to emit the vtable in each 1771 translation unit containing a definition, we would get 1772 multiple definition errors at link-time. */ 1773 if (method && (flag_weak || ! DECL_DECLARED_INLINE_P (method))) 1774 import_export = (DECL_REALLY_EXTERN (method) ? -1 : 1); 1775 } 1776 1777 /* When MULTIPLE_SYMBOL_SPACES is set, we cannot count on seeing 1778 a definition anywhere else. */ 1779 if (MULTIPLE_SYMBOL_SPACES && import_export == -1) 1780 import_export = 0; 1781 1782 /* Allow back ends the chance to overrule the decision. */ 1783 if (targetm.cxx.import_export_class) 1784 import_export = targetm.cxx.import_export_class (ctype, import_export); 1785 1786 if (import_export) 1787 { 1788 SET_CLASSTYPE_INTERFACE_KNOWN (ctype); 1789 CLASSTYPE_INTERFACE_ONLY (ctype) = (import_export < 0); 1790 } 1791 } 1792 1793 /* Return true if VAR has already been provided to the back end; in that 1794 case VAR should not be modified further by the front end. */ 1795 static bool 1796 var_finalized_p (tree var) 1797 { 1798 return varpool_node_for_decl (var)->finalized; 1799 } 1800 1801 /* DECL is a VAR_DECL or FUNCTION_DECL which, for whatever reason, 1802 must be emitted in this translation unit. Mark it as such. */ 1803 1804 void 1805 mark_needed (tree decl) 1806 { 1807 TREE_USED (decl) = 1; 1808 mark_decl_referenced (decl); 1809 } 1810 1811 /* DECL is either a FUNCTION_DECL or a VAR_DECL. This function 1812 returns true if a definition of this entity should be provided in 1813 this object file. Callers use this function to determine whether 1814 or not to let the back end know that a definition of DECL is 1815 available in this translation unit. */ 1816 1817 bool 1818 decl_needed_p (tree decl) 1819 { 1820 gcc_assert (TREE_CODE (decl) == VAR_DECL 1821 || TREE_CODE (decl) == FUNCTION_DECL); 1822 /* This function should only be called at the end of the translation 1823 unit. We cannot be sure of whether or not something will be 1824 COMDAT until that point. */ 1825 gcc_assert (at_eof); 1826 1827 /* All entities with external linkage that are not COMDAT should be 1828 emitted; they may be referred to from other object files. */ 1829 if (TREE_PUBLIC (decl) && !DECL_COMDAT (decl)) 1830 return true; 1831 /* If this entity was used, let the back end see it; it will decide 1832 whether or not to emit it into the object file. */ 1833 if (TREE_USED (decl)) 1834 return true; 1835 /* Functions marked "dllexport" must be emitted so that they are 1836 visible to other DLLs. */ 1837 if (flag_keep_inline_dllexport 1838 && lookup_attribute ("dllexport", DECL_ATTRIBUTES (decl))) 1839 return true; 1840 /* Otherwise, DECL does not need to be emitted -- yet. A subsequent 1841 reference to DECL might cause it to be emitted later. */ 1842 return false; 1843 } 1844 1845 /* If necessary, write out the vtables for the dynamic class CTYPE. 1846 Returns true if any vtables were emitted. */ 1847 1848 static bool 1849 maybe_emit_vtables (tree ctype) 1850 { 1851 tree vtbl; 1852 tree primary_vtbl; 1853 int needed = 0; 1854 struct varpool_node *current = NULL, *last = NULL; 1855 1856 /* If the vtables for this class have already been emitted there is 1857 nothing more to do. */ 1858 primary_vtbl = CLASSTYPE_VTABLES (ctype); 1859 if (var_finalized_p (primary_vtbl)) 1860 return false; 1861 /* Ignore dummy vtables made by get_vtable_decl. */ 1862 if (TREE_TYPE (primary_vtbl) == void_type_node) 1863 return false; 1864 1865 /* On some targets, we cannot determine the key method until the end 1866 of the translation unit -- which is when this function is 1867 called. */ 1868 if (!targetm.cxx.key_method_may_be_inline ()) 1869 determine_key_method (ctype); 1870 1871 /* See if any of the vtables are needed. */ 1872 for (vtbl = CLASSTYPE_VTABLES (ctype); vtbl; vtbl = DECL_CHAIN (vtbl)) 1873 { 1874 import_export_decl (vtbl); 1875 if (DECL_NOT_REALLY_EXTERN (vtbl) && decl_needed_p (vtbl)) 1876 needed = 1; 1877 } 1878 if (!needed) 1879 { 1880 /* If the references to this class' vtables are optimized away, 1881 still emit the appropriate debugging information. See 1882 dfs_debug_mark. */ 1883 if (DECL_COMDAT (primary_vtbl) 1884 && CLASSTYPE_DEBUG_REQUESTED (ctype)) 1885 note_debug_info_needed (ctype); 1886 return false; 1887 } 1888 1889 /* The ABI requires that we emit all of the vtables if we emit any 1890 of them. */ 1891 for (vtbl = CLASSTYPE_VTABLES (ctype); vtbl; vtbl = DECL_CHAIN (vtbl)) 1892 { 1893 /* Mark entities references from the virtual table as used. */ 1894 mark_vtable_entries (vtbl); 1895 1896 if (TREE_TYPE (DECL_INITIAL (vtbl)) == 0) 1897 { 1898 vec<tree, va_gc> *cleanups = NULL; 1899 tree expr = store_init_value (vtbl, DECL_INITIAL (vtbl), &cleanups, 1900 LOOKUP_NORMAL); 1901 1902 /* It had better be all done at compile-time. */ 1903 gcc_assert (!expr && !cleanups); 1904 } 1905 1906 /* Write it out. */ 1907 DECL_EXTERNAL (vtbl) = 0; 1908 rest_of_decl_compilation (vtbl, 1, 1); 1909 1910 /* Because we're only doing syntax-checking, we'll never end up 1911 actually marking the variable as written. */ 1912 if (flag_syntax_only) 1913 TREE_ASM_WRITTEN (vtbl) = 1; 1914 else if (DECL_ONE_ONLY (vtbl)) 1915 { 1916 current = varpool_node_for_decl (vtbl); 1917 if (last) 1918 symtab_add_to_same_comdat_group ((symtab_node) current, (symtab_node) last); 1919 last = current; 1920 } 1921 } 1922 1923 /* Since we're writing out the vtable here, also write the debug 1924 info. */ 1925 note_debug_info_needed (ctype); 1926 1927 return true; 1928 } 1929 1930 /* A special return value from type_visibility meaning internal 1931 linkage. */ 1932 1933 enum { VISIBILITY_ANON = VISIBILITY_INTERNAL+1 }; 1934 1935 /* walk_tree helper function for type_visibility. */ 1936 1937 static tree 1938 min_vis_r (tree *tp, int *walk_subtrees, void *data) 1939 { 1940 int *vis_p = (int *)data; 1941 if (! TYPE_P (*tp)) 1942 { 1943 *walk_subtrees = 0; 1944 } 1945 else if (TAGGED_TYPE_P (*tp) 1946 && !TREE_PUBLIC (TYPE_MAIN_DECL (*tp))) 1947 { 1948 *vis_p = VISIBILITY_ANON; 1949 return *tp; 1950 } 1951 else if (CLASS_TYPE_P (*tp) 1952 && CLASSTYPE_VISIBILITY (*tp) > *vis_p) 1953 *vis_p = CLASSTYPE_VISIBILITY (*tp); 1954 return NULL; 1955 } 1956 1957 /* Returns the visibility of TYPE, which is the minimum visibility of its 1958 component types. */ 1959 1960 static int 1961 type_visibility (tree type) 1962 { 1963 int vis = VISIBILITY_DEFAULT; 1964 cp_walk_tree_without_duplicates (&type, min_vis_r, &vis); 1965 return vis; 1966 } 1967 1968 /* Limit the visibility of DECL to VISIBILITY, if not explicitly 1969 specified (or if VISIBILITY is static). If TMPL is true, this 1970 constraint is for a template argument, and takes precedence 1971 over explicitly-specified visibility on the template. */ 1972 1973 static void 1974 constrain_visibility (tree decl, int visibility, bool tmpl) 1975 { 1976 if (visibility == VISIBILITY_ANON) 1977 { 1978 /* extern "C" declarations aren't affected by the anonymous 1979 namespace. */ 1980 if (!DECL_EXTERN_C_P (decl)) 1981 { 1982 TREE_PUBLIC (decl) = 0; 1983 DECL_WEAK (decl) = 0; 1984 DECL_COMMON (decl) = 0; 1985 DECL_COMDAT_GROUP (decl) = NULL_TREE; 1986 DECL_INTERFACE_KNOWN (decl) = 1; 1987 if (DECL_LANG_SPECIFIC (decl)) 1988 DECL_NOT_REALLY_EXTERN (decl) = 1; 1989 } 1990 } 1991 else if (visibility > DECL_VISIBILITY (decl) 1992 && (tmpl || !DECL_VISIBILITY_SPECIFIED (decl))) 1993 { 1994 DECL_VISIBILITY (decl) = (enum symbol_visibility) visibility; 1995 /* This visibility was not specified. */ 1996 DECL_VISIBILITY_SPECIFIED (decl) = false; 1997 } 1998 } 1999 2000 /* Constrain the visibility of DECL based on the visibility of its template 2001 arguments. */ 2002 2003 static void 2004 constrain_visibility_for_template (tree decl, tree targs) 2005 { 2006 /* If this is a template instantiation, check the innermost 2007 template args for visibility constraints. The outer template 2008 args are covered by the class check. */ 2009 tree args = INNERMOST_TEMPLATE_ARGS (targs); 2010 int i; 2011 for (i = TREE_VEC_LENGTH (args); i > 0; --i) 2012 { 2013 int vis = 0; 2014 2015 tree arg = TREE_VEC_ELT (args, i-1); 2016 if (TYPE_P (arg)) 2017 vis = type_visibility (arg); 2018 else if (TREE_TYPE (arg) && POINTER_TYPE_P (TREE_TYPE (arg))) 2019 { 2020 STRIP_NOPS (arg); 2021 if (TREE_CODE (arg) == ADDR_EXPR) 2022 arg = TREE_OPERAND (arg, 0); 2023 if (TREE_CODE (arg) == VAR_DECL 2024 || TREE_CODE (arg) == FUNCTION_DECL) 2025 { 2026 if (! TREE_PUBLIC (arg)) 2027 vis = VISIBILITY_ANON; 2028 else 2029 vis = DECL_VISIBILITY (arg); 2030 } 2031 } 2032 if (vis) 2033 constrain_visibility (decl, vis, true); 2034 } 2035 } 2036 2037 /* Like c_determine_visibility, but with additional C++-specific 2038 behavior. 2039 2040 Function-scope entities can rely on the function's visibility because 2041 it is set in start_preparsed_function. 2042 2043 Class-scope entities cannot rely on the class's visibility until the end 2044 of the enclosing class definition. 2045 2046 Note that because namespaces have multiple independent definitions, 2047 namespace visibility is handled elsewhere using the #pragma visibility 2048 machinery rather than by decorating the namespace declaration. 2049 2050 The goal is for constraints from the type to give a diagnostic, and 2051 other constraints to be applied silently. */ 2052 2053 void 2054 determine_visibility (tree decl) 2055 { 2056 tree class_type = NULL_TREE; 2057 bool use_template; 2058 bool orig_visibility_specified; 2059 enum symbol_visibility orig_visibility; 2060 2061 /* Remember that all decls get VISIBILITY_DEFAULT when built. */ 2062 2063 /* Only relevant for names with external linkage. */ 2064 if (!TREE_PUBLIC (decl)) 2065 return; 2066 2067 /* Cloned constructors and destructors get the same visibility as 2068 the underlying function. That should be set up in 2069 maybe_clone_body. */ 2070 gcc_assert (!DECL_CLONED_FUNCTION_P (decl)); 2071 2072 orig_visibility_specified = DECL_VISIBILITY_SPECIFIED (decl); 2073 orig_visibility = DECL_VISIBILITY (decl); 2074 2075 if (TREE_CODE (decl) == TYPE_DECL) 2076 { 2077 if (CLASS_TYPE_P (TREE_TYPE (decl))) 2078 use_template = CLASSTYPE_USE_TEMPLATE (TREE_TYPE (decl)); 2079 else if (TYPE_TEMPLATE_INFO (TREE_TYPE (decl))) 2080 use_template = 1; 2081 else 2082 use_template = 0; 2083 } 2084 else if (DECL_LANG_SPECIFIC (decl)) 2085 use_template = DECL_USE_TEMPLATE (decl); 2086 else 2087 use_template = 0; 2088 2089 /* If DECL is a member of a class, visibility specifiers on the 2090 class can influence the visibility of the DECL. */ 2091 if (DECL_CLASS_SCOPE_P (decl)) 2092 class_type = DECL_CONTEXT (decl); 2093 else 2094 { 2095 /* Not a class member. */ 2096 2097 /* Virtual tables have DECL_CONTEXT set to their associated class, 2098 so they are automatically handled above. */ 2099 gcc_assert (TREE_CODE (decl) != VAR_DECL 2100 || !DECL_VTABLE_OR_VTT_P (decl)); 2101 2102 if (DECL_FUNCTION_SCOPE_P (decl) && ! DECL_VISIBILITY_SPECIFIED (decl)) 2103 { 2104 /* Local statics and classes get the visibility of their 2105 containing function by default, except that 2106 -fvisibility-inlines-hidden doesn't affect them. */ 2107 tree fn = DECL_CONTEXT (decl); 2108 if (DECL_VISIBILITY_SPECIFIED (fn)) 2109 { 2110 DECL_VISIBILITY (decl) = DECL_VISIBILITY (fn); 2111 DECL_VISIBILITY_SPECIFIED (decl) = 2112 DECL_VISIBILITY_SPECIFIED (fn); 2113 } 2114 else 2115 { 2116 if (DECL_CLASS_SCOPE_P (fn)) 2117 determine_visibility_from_class (decl, DECL_CONTEXT (fn)); 2118 else if (determine_hidden_inline (fn)) 2119 { 2120 DECL_VISIBILITY (decl) = default_visibility; 2121 DECL_VISIBILITY_SPECIFIED (decl) = 2122 visibility_options.inpragma; 2123 } 2124 else 2125 { 2126 DECL_VISIBILITY (decl) = DECL_VISIBILITY (fn); 2127 DECL_VISIBILITY_SPECIFIED (decl) = 2128 DECL_VISIBILITY_SPECIFIED (fn); 2129 } 2130 } 2131 2132 /* Local classes in templates have CLASSTYPE_USE_TEMPLATE set, 2133 but have no TEMPLATE_INFO, so don't try to check it. */ 2134 use_template = 0; 2135 } 2136 else if (TREE_CODE (decl) == VAR_DECL && DECL_TINFO_P (decl) 2137 && flag_visibility_ms_compat) 2138 { 2139 /* Under -fvisibility-ms-compat, types are visible by default, 2140 even though their contents aren't. */ 2141 tree underlying_type = TREE_TYPE (DECL_NAME (decl)); 2142 int underlying_vis = type_visibility (underlying_type); 2143 if (underlying_vis == VISIBILITY_ANON 2144 || (CLASS_TYPE_P (underlying_type) 2145 && CLASSTYPE_VISIBILITY_SPECIFIED (underlying_type))) 2146 constrain_visibility (decl, underlying_vis, false); 2147 else 2148 DECL_VISIBILITY (decl) = VISIBILITY_DEFAULT; 2149 } 2150 else if (TREE_CODE (decl) == VAR_DECL && DECL_TINFO_P (decl)) 2151 { 2152 /* tinfo visibility is based on the type it's for. */ 2153 constrain_visibility 2154 (decl, type_visibility (TREE_TYPE (DECL_NAME (decl))), false); 2155 2156 /* Give the target a chance to override the visibility associated 2157 with DECL. */ 2158 if (TREE_PUBLIC (decl) 2159 && !DECL_REALLY_EXTERN (decl) 2160 && CLASS_TYPE_P (TREE_TYPE (DECL_NAME (decl))) 2161 && !CLASSTYPE_VISIBILITY_SPECIFIED (TREE_TYPE (DECL_NAME (decl)))) 2162 targetm.cxx.determine_class_data_visibility (decl); 2163 } 2164 else if (use_template) 2165 /* Template instantiations and specializations get visibility based 2166 on their template unless they override it with an attribute. */; 2167 else if (! DECL_VISIBILITY_SPECIFIED (decl)) 2168 { 2169 if (determine_hidden_inline (decl)) 2170 DECL_VISIBILITY (decl) = VISIBILITY_HIDDEN; 2171 else 2172 { 2173 /* Set default visibility to whatever the user supplied with 2174 #pragma GCC visibility or a namespace visibility attribute. */ 2175 DECL_VISIBILITY (decl) = default_visibility; 2176 DECL_VISIBILITY_SPECIFIED (decl) = visibility_options.inpragma; 2177 } 2178 } 2179 } 2180 2181 if (use_template) 2182 { 2183 /* If the specialization doesn't specify visibility, use the 2184 visibility from the template. */ 2185 tree tinfo = (TREE_CODE (decl) == TYPE_DECL 2186 ? TYPE_TEMPLATE_INFO (TREE_TYPE (decl)) 2187 : DECL_TEMPLATE_INFO (decl)); 2188 tree args = TI_ARGS (tinfo); 2189 tree attribs = (TREE_CODE (decl) == TYPE_DECL 2190 ? TYPE_ATTRIBUTES (TREE_TYPE (decl)) 2191 : DECL_ATTRIBUTES (decl)); 2192 2193 if (args != error_mark_node) 2194 { 2195 tree pattern = DECL_TEMPLATE_RESULT (TI_TEMPLATE (tinfo)); 2196 2197 if (!DECL_VISIBILITY_SPECIFIED (decl)) 2198 { 2199 if (!DECL_VISIBILITY_SPECIFIED (pattern) 2200 && determine_hidden_inline (decl)) 2201 DECL_VISIBILITY (decl) = VISIBILITY_HIDDEN; 2202 else 2203 { 2204 DECL_VISIBILITY (decl) = DECL_VISIBILITY (pattern); 2205 DECL_VISIBILITY_SPECIFIED (decl) 2206 = DECL_VISIBILITY_SPECIFIED (pattern); 2207 } 2208 } 2209 2210 if (args 2211 /* Template argument visibility outweighs #pragma or namespace 2212 visibility, but not an explicit attribute. */ 2213 && !lookup_attribute ("visibility", attribs)) 2214 { 2215 int depth = TMPL_ARGS_DEPTH (args); 2216 if (DECL_VISIBILITY_SPECIFIED (decl)) 2217 { 2218 /* A class template member with explicit visibility 2219 overrides the class visibility, so we need to apply 2220 all the levels of template args directly. */ 2221 int i; 2222 for (i = 1; i <= depth; ++i) 2223 { 2224 tree lev = TMPL_ARGS_LEVEL (args, i); 2225 constrain_visibility_for_template (decl, lev); 2226 } 2227 } 2228 else if (PRIMARY_TEMPLATE_P (TI_TEMPLATE (tinfo))) 2229 /* Limit visibility based on its template arguments. */ 2230 constrain_visibility_for_template (decl, args); 2231 } 2232 } 2233 } 2234 2235 if (class_type) 2236 determine_visibility_from_class (decl, class_type); 2237 2238 if (decl_anon_ns_mem_p (decl)) 2239 /* Names in an anonymous namespace get internal linkage. 2240 This might change once we implement export. */ 2241 constrain_visibility (decl, VISIBILITY_ANON, false); 2242 else if (TREE_CODE (decl) != TYPE_DECL) 2243 { 2244 /* Propagate anonymity from type to decl. */ 2245 int tvis = type_visibility (TREE_TYPE (decl)); 2246 if (tvis == VISIBILITY_ANON 2247 || ! DECL_VISIBILITY_SPECIFIED (decl)) 2248 constrain_visibility (decl, tvis, false); 2249 } 2250 else if (no_linkage_check (TREE_TYPE (decl), /*relaxed_p=*/true)) 2251 /* DR 757: A type without linkage shall not be used as the type of a 2252 variable or function with linkage, unless 2253 o the variable or function has extern "C" linkage (7.5 [dcl.link]), or 2254 o the variable or function is not used (3.2 [basic.def.odr]) or is 2255 defined in the same translation unit. 2256 2257 Since non-extern "C" decls need to be defined in the same 2258 translation unit, we can make the type internal. */ 2259 constrain_visibility (decl, VISIBILITY_ANON, false); 2260 2261 /* If visibility changed and DECL already has DECL_RTL, ensure 2262 symbol flags are updated. */ 2263 if ((DECL_VISIBILITY (decl) != orig_visibility 2264 || DECL_VISIBILITY_SPECIFIED (decl) != orig_visibility_specified) 2265 && ((TREE_CODE (decl) == VAR_DECL && TREE_STATIC (decl)) 2266 || TREE_CODE (decl) == FUNCTION_DECL) 2267 && DECL_RTL_SET_P (decl)) 2268 make_decl_rtl (decl); 2269 } 2270 2271 /* By default, static data members and function members receive 2272 the visibility of their containing class. */ 2273 2274 static void 2275 determine_visibility_from_class (tree decl, tree class_type) 2276 { 2277 if (DECL_VISIBILITY_SPECIFIED (decl)) 2278 return; 2279 2280 if (determine_hidden_inline (decl)) 2281 DECL_VISIBILITY (decl) = VISIBILITY_HIDDEN; 2282 else 2283 { 2284 /* Default to the class visibility. */ 2285 DECL_VISIBILITY (decl) = CLASSTYPE_VISIBILITY (class_type); 2286 DECL_VISIBILITY_SPECIFIED (decl) 2287 = CLASSTYPE_VISIBILITY_SPECIFIED (class_type); 2288 } 2289 2290 /* Give the target a chance to override the visibility associated 2291 with DECL. */ 2292 if (TREE_CODE (decl) == VAR_DECL 2293 && (DECL_TINFO_P (decl) 2294 || (DECL_VTABLE_OR_VTT_P (decl) 2295 /* Construction virtual tables are not exported because 2296 they cannot be referred to from other object files; 2297 their name is not standardized by the ABI. */ 2298 && !DECL_CONSTRUCTION_VTABLE_P (decl))) 2299 && TREE_PUBLIC (decl) 2300 && !DECL_REALLY_EXTERN (decl) 2301 && !CLASSTYPE_VISIBILITY_SPECIFIED (class_type)) 2302 targetm.cxx.determine_class_data_visibility (decl); 2303 } 2304 2305 /* Returns true iff DECL is an inline that should get hidden visibility 2306 because of -fvisibility-inlines-hidden. */ 2307 2308 static bool 2309 determine_hidden_inline (tree decl) 2310 { 2311 return (visibility_options.inlines_hidden 2312 /* Don't do this for inline templates; specializations might not be 2313 inline, and we don't want them to inherit the hidden 2314 visibility. We'll set it here for all inline instantiations. */ 2315 && !processing_template_decl 2316 && TREE_CODE (decl) == FUNCTION_DECL 2317 && DECL_DECLARED_INLINE_P (decl) 2318 && (! DECL_LANG_SPECIFIC (decl) 2319 || ! DECL_EXPLICIT_INSTANTIATION (decl))); 2320 } 2321 2322 /* Constrain the visibility of a class TYPE based on the visibility of its 2323 field types. Warn if any fields require lesser visibility. */ 2324 2325 void 2326 constrain_class_visibility (tree type) 2327 { 2328 tree binfo; 2329 tree t; 2330 int i; 2331 2332 int vis = type_visibility (type); 2333 2334 if (vis == VISIBILITY_ANON 2335 || DECL_IN_SYSTEM_HEADER (TYPE_MAIN_DECL (type))) 2336 return; 2337 2338 /* Don't warn about visibility if the class has explicit visibility. */ 2339 if (CLASSTYPE_VISIBILITY_SPECIFIED (type)) 2340 vis = VISIBILITY_INTERNAL; 2341 2342 for (t = TYPE_FIELDS (type); t; t = DECL_CHAIN (t)) 2343 if (TREE_CODE (t) == FIELD_DECL && TREE_TYPE (t) != error_mark_node) 2344 { 2345 tree ftype = strip_pointer_or_array_types (TREE_TYPE (t)); 2346 int subvis = type_visibility (ftype); 2347 2348 if (subvis == VISIBILITY_ANON) 2349 { 2350 if (!in_main_input_context ()) 2351 warning (0, "\ 2352 %qT has a field %qD whose type uses the anonymous namespace", 2353 type, t); 2354 } 2355 else if (MAYBE_CLASS_TYPE_P (ftype) 2356 && vis < VISIBILITY_HIDDEN 2357 && subvis >= VISIBILITY_HIDDEN) 2358 warning (OPT_Wattributes, "\ 2359 %qT declared with greater visibility than the type of its field %qD", 2360 type, t); 2361 } 2362 2363 binfo = TYPE_BINFO (type); 2364 for (i = 0; BINFO_BASE_ITERATE (binfo, i, t); ++i) 2365 { 2366 int subvis = type_visibility (TREE_TYPE (t)); 2367 2368 if (subvis == VISIBILITY_ANON) 2369 { 2370 if (!in_main_input_context()) 2371 warning (0, "\ 2372 %qT has a base %qT whose type uses the anonymous namespace", 2373 type, TREE_TYPE (t)); 2374 } 2375 else if (vis < VISIBILITY_HIDDEN 2376 && subvis >= VISIBILITY_HIDDEN) 2377 warning (OPT_Wattributes, "\ 2378 %qT declared with greater visibility than its base %qT", 2379 type, TREE_TYPE (t)); 2380 } 2381 } 2382 2383 /* DECL is a FUNCTION_DECL or VAR_DECL. If the object file linkage 2384 for DECL has not already been determined, do so now by setting 2385 DECL_EXTERNAL, DECL_COMDAT and other related flags. Until this 2386 function is called entities with vague linkage whose definitions 2387 are available must have TREE_PUBLIC set. 2388 2389 If this function decides to place DECL in COMDAT, it will set 2390 appropriate flags -- but will not clear DECL_EXTERNAL. It is up to 2391 the caller to decide whether or not to clear DECL_EXTERNAL. Some 2392 callers defer that decision until it is clear that DECL is actually 2393 required. */ 2394 2395 void 2396 import_export_decl (tree decl) 2397 { 2398 int emit_p; 2399 bool comdat_p; 2400 bool import_p; 2401 tree class_type = NULL_TREE; 2402 2403 if (DECL_INTERFACE_KNOWN (decl)) 2404 return; 2405 2406 /* We cannot determine what linkage to give to an entity with vague 2407 linkage until the end of the file. For example, a virtual table 2408 for a class will be defined if and only if the key method is 2409 defined in this translation unit. As a further example, consider 2410 that when compiling a translation unit that uses PCH file with 2411 "-frepo" it would be incorrect to make decisions about what 2412 entities to emit when building the PCH; those decisions must be 2413 delayed until the repository information has been processed. */ 2414 gcc_assert (at_eof); 2415 /* Object file linkage for explicit instantiations is handled in 2416 mark_decl_instantiated. For static variables in functions with 2417 vague linkage, maybe_commonize_var is used. 2418 2419 Therefore, the only declarations that should be provided to this 2420 function are those with external linkage that are: 2421 2422 * implicit instantiations of function templates 2423 2424 * inline function 2425 2426 * implicit instantiations of static data members of class 2427 templates 2428 2429 * virtual tables 2430 2431 * typeinfo objects 2432 2433 Furthermore, all entities that reach this point must have a 2434 definition available in this translation unit. 2435 2436 The following assertions check these conditions. */ 2437 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL 2438 || TREE_CODE (decl) == VAR_DECL); 2439 /* Any code that creates entities with TREE_PUBLIC cleared should 2440 also set DECL_INTERFACE_KNOWN. */ 2441 gcc_assert (TREE_PUBLIC (decl)); 2442 if (TREE_CODE (decl) == FUNCTION_DECL) 2443 gcc_assert (DECL_IMPLICIT_INSTANTIATION (decl) 2444 || DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (decl) 2445 || DECL_DECLARED_INLINE_P (decl)); 2446 else 2447 gcc_assert (DECL_IMPLICIT_INSTANTIATION (decl) 2448 || DECL_VTABLE_OR_VTT_P (decl) 2449 || DECL_TINFO_P (decl)); 2450 /* Check that a definition of DECL is available in this translation 2451 unit. */ 2452 gcc_assert (!DECL_REALLY_EXTERN (decl)); 2453 2454 /* Assume that DECL will not have COMDAT linkage. */ 2455 comdat_p = false; 2456 /* Assume that DECL will not be imported into this translation 2457 unit. */ 2458 import_p = false; 2459 2460 /* See if the repository tells us whether or not to emit DECL in 2461 this translation unit. */ 2462 emit_p = repo_emit_p (decl); 2463 if (emit_p == 0) 2464 import_p = true; 2465 else if (emit_p == 1) 2466 { 2467 /* The repository indicates that this entity should be defined 2468 here. Make sure the back end honors that request. */ 2469 if (TREE_CODE (decl) == VAR_DECL) 2470 mark_needed (decl); 2471 else if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (decl) 2472 || DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (decl)) 2473 { 2474 tree clone; 2475 FOR_EACH_CLONE (clone, decl) 2476 mark_needed (clone); 2477 } 2478 else 2479 mark_needed (decl); 2480 /* Output the definition as an ordinary strong definition. */ 2481 DECL_EXTERNAL (decl) = 0; 2482 DECL_INTERFACE_KNOWN (decl) = 1; 2483 return; 2484 } 2485 2486 if (import_p) 2487 /* We have already decided what to do with this DECL; there is no 2488 need to check anything further. */ 2489 ; 2490 else if (TREE_CODE (decl) == VAR_DECL && DECL_VTABLE_OR_VTT_P (decl)) 2491 { 2492 class_type = DECL_CONTEXT (decl); 2493 import_export_class (class_type); 2494 if (TYPE_FOR_JAVA (class_type)) 2495 import_p = true; 2496 else if (CLASSTYPE_INTERFACE_KNOWN (class_type) 2497 && CLASSTYPE_INTERFACE_ONLY (class_type)) 2498 import_p = true; 2499 else if ((!flag_weak || TARGET_WEAK_NOT_IN_ARCHIVE_TOC) 2500 && !CLASSTYPE_USE_TEMPLATE (class_type) 2501 && CLASSTYPE_KEY_METHOD (class_type) 2502 && !DECL_DECLARED_INLINE_P (CLASSTYPE_KEY_METHOD (class_type))) 2503 /* The ABI requires that all virtual tables be emitted with 2504 COMDAT linkage. However, on systems where COMDAT symbols 2505 don't show up in the table of contents for a static 2506 archive, or on systems without weak symbols (where we 2507 approximate COMDAT linkage by using internal linkage), the 2508 linker will report errors about undefined symbols because 2509 it will not see the virtual table definition. Therefore, 2510 in the case that we know that the virtual table will be 2511 emitted in only one translation unit, we make the virtual 2512 table an ordinary definition with external linkage. */ 2513 DECL_EXTERNAL (decl) = 0; 2514 else if (CLASSTYPE_INTERFACE_KNOWN (class_type)) 2515 { 2516 /* CLASS_TYPE is being exported from this translation unit, 2517 so DECL should be defined here. */ 2518 if (!flag_weak && CLASSTYPE_EXPLICIT_INSTANTIATION (class_type)) 2519 /* If a class is declared in a header with the "extern 2520 template" extension, then it will not be instantiated, 2521 even in translation units that would normally require 2522 it. Often such classes are explicitly instantiated in 2523 one translation unit. Therefore, the explicit 2524 instantiation must be made visible to other translation 2525 units. */ 2526 DECL_EXTERNAL (decl) = 0; 2527 else 2528 { 2529 /* The generic C++ ABI says that class data is always 2530 COMDAT, even if there is a key function. Some 2531 variants (e.g., the ARM EABI) says that class data 2532 only has COMDAT linkage if the class data might be 2533 emitted in more than one translation unit. When the 2534 key method can be inline and is inline, we still have 2535 to arrange for comdat even though 2536 class_data_always_comdat is false. */ 2537 if (!CLASSTYPE_KEY_METHOD (class_type) 2538 || DECL_DECLARED_INLINE_P (CLASSTYPE_KEY_METHOD (class_type)) 2539 || targetm.cxx.class_data_always_comdat ()) 2540 { 2541 /* The ABI requires COMDAT linkage. Normally, we 2542 only emit COMDAT things when they are needed; 2543 make sure that we realize that this entity is 2544 indeed needed. */ 2545 comdat_p = true; 2546 mark_needed (decl); 2547 } 2548 } 2549 } 2550 else if (!flag_implicit_templates 2551 && CLASSTYPE_IMPLICIT_INSTANTIATION (class_type)) 2552 import_p = true; 2553 else 2554 comdat_p = true; 2555 } 2556 else if (TREE_CODE (decl) == VAR_DECL && DECL_TINFO_P (decl)) 2557 { 2558 tree type = TREE_TYPE (DECL_NAME (decl)); 2559 if (CLASS_TYPE_P (type)) 2560 { 2561 class_type = type; 2562 import_export_class (type); 2563 if (CLASSTYPE_INTERFACE_KNOWN (type) 2564 && TYPE_POLYMORPHIC_P (type) 2565 && CLASSTYPE_INTERFACE_ONLY (type) 2566 /* If -fno-rtti was specified, then we cannot be sure 2567 that RTTI information will be emitted with the 2568 virtual table of the class, so we must emit it 2569 wherever it is used. */ 2570 && flag_rtti) 2571 import_p = true; 2572 else 2573 { 2574 if (CLASSTYPE_INTERFACE_KNOWN (type) 2575 && !CLASSTYPE_INTERFACE_ONLY (type)) 2576 { 2577 comdat_p = (targetm.cxx.class_data_always_comdat () 2578 || (CLASSTYPE_KEY_METHOD (type) 2579 && DECL_DECLARED_INLINE_P (CLASSTYPE_KEY_METHOD (type)))); 2580 mark_needed (decl); 2581 if (!flag_weak) 2582 { 2583 comdat_p = false; 2584 DECL_EXTERNAL (decl) = 0; 2585 } 2586 } 2587 else 2588 comdat_p = true; 2589 } 2590 } 2591 else 2592 comdat_p = true; 2593 } 2594 else if (DECL_TEMPLATE_INSTANTIATION (decl) 2595 || DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (decl)) 2596 { 2597 /* DECL is an implicit instantiation of a function or static 2598 data member. */ 2599 if ((flag_implicit_templates 2600 && !flag_use_repository) 2601 || (flag_implicit_inline_templates 2602 && TREE_CODE (decl) == FUNCTION_DECL 2603 && DECL_DECLARED_INLINE_P (decl))) 2604 comdat_p = true; 2605 else 2606 /* If we are not implicitly generating templates, then mark 2607 this entity as undefined in this translation unit. */ 2608 import_p = true; 2609 } 2610 else if (DECL_FUNCTION_MEMBER_P (decl)) 2611 { 2612 if (!DECL_DECLARED_INLINE_P (decl)) 2613 { 2614 tree ctype = DECL_CONTEXT (decl); 2615 import_export_class (ctype); 2616 if (CLASSTYPE_INTERFACE_KNOWN (ctype)) 2617 { 2618 DECL_NOT_REALLY_EXTERN (decl) 2619 = ! (CLASSTYPE_INTERFACE_ONLY (ctype) 2620 || (DECL_DECLARED_INLINE_P (decl) 2621 && ! flag_implement_inlines 2622 && !DECL_VINDEX (decl))); 2623 2624 if (!DECL_NOT_REALLY_EXTERN (decl)) 2625 DECL_EXTERNAL (decl) = 1; 2626 2627 /* Always make artificials weak. */ 2628 if (DECL_ARTIFICIAL (decl) && flag_weak) 2629 comdat_p = true; 2630 else 2631 maybe_make_one_only (decl); 2632 } 2633 } 2634 else 2635 comdat_p = true; 2636 } 2637 else 2638 comdat_p = true; 2639 2640 if (import_p) 2641 { 2642 /* If we are importing DECL into this translation unit, mark is 2643 an undefined here. */ 2644 DECL_EXTERNAL (decl) = 1; 2645 DECL_NOT_REALLY_EXTERN (decl) = 0; 2646 } 2647 else if (comdat_p) 2648 { 2649 /* If we decided to put DECL in COMDAT, mark it accordingly at 2650 this point. */ 2651 comdat_linkage (decl); 2652 } 2653 2654 DECL_INTERFACE_KNOWN (decl) = 1; 2655 } 2656 2657 /* Return an expression that performs the destruction of DECL, which 2658 must be a VAR_DECL whose type has a non-trivial destructor, or is 2659 an array whose (innermost) elements have a non-trivial destructor. */ 2660 2661 tree 2662 build_cleanup (tree decl) 2663 { 2664 tree temp; 2665 tree type = TREE_TYPE (decl); 2666 2667 /* This function should only be called for declarations that really 2668 require cleanups. */ 2669 gcc_assert (!TYPE_HAS_TRIVIAL_DESTRUCTOR (type)); 2670 2671 /* Treat all objects with destructors as used; the destructor may do 2672 something substantive. */ 2673 mark_used (decl); 2674 2675 if (TREE_CODE (type) == ARRAY_TYPE) 2676 temp = decl; 2677 else 2678 temp = build_address (decl); 2679 temp = build_delete (TREE_TYPE (temp), temp, 2680 sfk_complete_destructor, 2681 LOOKUP_NORMAL|LOOKUP_NONVIRTUAL|LOOKUP_DESTRUCTOR, 0, 2682 tf_warning_or_error); 2683 return temp; 2684 } 2685 2686 /* Returns the initialization guard variable for the variable DECL, 2687 which has static storage duration. */ 2688 2689 tree 2690 get_guard (tree decl) 2691 { 2692 tree sname; 2693 tree guard; 2694 2695 sname = mangle_guard_variable (decl); 2696 guard = IDENTIFIER_GLOBAL_VALUE (sname); 2697 if (! guard) 2698 { 2699 tree guard_type; 2700 2701 /* We use a type that is big enough to contain a mutex as well 2702 as an integer counter. */ 2703 guard_type = targetm.cxx.guard_type (); 2704 guard = build_decl (DECL_SOURCE_LOCATION (decl), 2705 VAR_DECL, sname, guard_type); 2706 2707 /* The guard should have the same linkage as what it guards. */ 2708 TREE_PUBLIC (guard) = TREE_PUBLIC (decl); 2709 TREE_STATIC (guard) = TREE_STATIC (decl); 2710 DECL_COMMON (guard) = DECL_COMMON (decl); 2711 DECL_COMDAT (guard) = DECL_COMDAT (decl); 2712 DECL_TLS_MODEL (guard) = DECL_TLS_MODEL (decl); 2713 if (DECL_ONE_ONLY (decl)) 2714 make_decl_one_only (guard, cxx_comdat_group (guard)); 2715 if (TREE_PUBLIC (decl)) 2716 DECL_WEAK (guard) = DECL_WEAK (decl); 2717 DECL_VISIBILITY (guard) = DECL_VISIBILITY (decl); 2718 DECL_VISIBILITY_SPECIFIED (guard) = DECL_VISIBILITY_SPECIFIED (decl); 2719 2720 DECL_ARTIFICIAL (guard) = 1; 2721 DECL_IGNORED_P (guard) = 1; 2722 TREE_USED (guard) = 1; 2723 pushdecl_top_level_and_finish (guard, NULL_TREE); 2724 } 2725 return guard; 2726 } 2727 2728 /* Return those bits of the GUARD variable that should be set when the 2729 guarded entity is actually initialized. */ 2730 2731 static tree 2732 get_guard_bits (tree guard) 2733 { 2734 if (!targetm.cxx.guard_mask_bit ()) 2735 { 2736 /* We only set the first byte of the guard, in order to leave room 2737 for a mutex in the high-order bits. */ 2738 guard = build1 (ADDR_EXPR, 2739 build_pointer_type (TREE_TYPE (guard)), 2740 guard); 2741 guard = build1 (NOP_EXPR, 2742 build_pointer_type (char_type_node), 2743 guard); 2744 guard = build1 (INDIRECT_REF, char_type_node, guard); 2745 } 2746 2747 return guard; 2748 } 2749 2750 /* Return an expression which determines whether or not the GUARD 2751 variable has already been initialized. */ 2752 2753 tree 2754 get_guard_cond (tree guard) 2755 { 2756 tree guard_value; 2757 2758 /* Check to see if the GUARD is zero. */ 2759 guard = get_guard_bits (guard); 2760 2761 /* Mask off all but the low bit. */ 2762 if (targetm.cxx.guard_mask_bit ()) 2763 { 2764 guard_value = integer_one_node; 2765 if (!same_type_p (TREE_TYPE (guard_value), TREE_TYPE (guard))) 2766 guard_value = convert (TREE_TYPE (guard), guard_value); 2767 guard = cp_build_binary_op (input_location, 2768 BIT_AND_EXPR, guard, guard_value, 2769 tf_warning_or_error); 2770 } 2771 2772 guard_value = integer_zero_node; 2773 if (!same_type_p (TREE_TYPE (guard_value), TREE_TYPE (guard))) 2774 guard_value = convert (TREE_TYPE (guard), guard_value); 2775 return cp_build_binary_op (input_location, 2776 EQ_EXPR, guard, guard_value, 2777 tf_warning_or_error); 2778 } 2779 2780 /* Return an expression which sets the GUARD variable, indicating that 2781 the variable being guarded has been initialized. */ 2782 2783 tree 2784 set_guard (tree guard) 2785 { 2786 tree guard_init; 2787 2788 /* Set the GUARD to one. */ 2789 guard = get_guard_bits (guard); 2790 guard_init = integer_one_node; 2791 if (!same_type_p (TREE_TYPE (guard_init), TREE_TYPE (guard))) 2792 guard_init = convert (TREE_TYPE (guard), guard_init); 2793 return cp_build_modify_expr (guard, NOP_EXPR, guard_init, 2794 tf_warning_or_error); 2795 } 2796 2797 /* Returns true iff we can tell that VAR does not have a dynamic 2798 initializer. */ 2799 2800 static bool 2801 var_defined_without_dynamic_init (tree var) 2802 { 2803 /* If it's defined in another TU, we can't tell. */ 2804 if (DECL_EXTERNAL (var)) 2805 return false; 2806 /* If it has a non-trivial destructor, registering the destructor 2807 counts as dynamic initialization. */ 2808 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TREE_TYPE (var))) 2809 return false; 2810 /* If it's in this TU, its initializer has been processed. */ 2811 gcc_assert (DECL_INITIALIZED_P (var)); 2812 /* If it has no initializer or a constant one, it's not dynamic. */ 2813 return (!DECL_NONTRIVIALLY_INITIALIZED_P (var) 2814 || DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (var)); 2815 } 2816 2817 /* Returns true iff VAR is a variable that needs uses to be 2818 wrapped for possible dynamic initialization. */ 2819 2820 static bool 2821 var_needs_tls_wrapper (tree var) 2822 { 2823 return (!error_operand_p (var) 2824 && DECL_THREAD_LOCAL_P (var) 2825 && !DECL_GNU_TLS_P (var) 2826 && !DECL_FUNCTION_SCOPE_P (var) 2827 && !var_defined_without_dynamic_init (var)); 2828 } 2829 2830 /* Get the FUNCTION_DECL for the shared TLS init function for this 2831 translation unit. */ 2832 2833 static tree 2834 get_local_tls_init_fn (void) 2835 { 2836 tree sname = get_identifier ("__tls_init"); 2837 tree fn = IDENTIFIER_GLOBAL_VALUE (sname); 2838 if (!fn) 2839 { 2840 fn = build_lang_decl (FUNCTION_DECL, sname, 2841 build_function_type (void_type_node, 2842 void_list_node)); 2843 SET_DECL_LANGUAGE (fn, lang_c); 2844 TREE_PUBLIC (fn) = false; 2845 DECL_ARTIFICIAL (fn) = true; 2846 mark_used (fn); 2847 SET_IDENTIFIER_GLOBAL_VALUE (sname, fn); 2848 } 2849 return fn; 2850 } 2851 2852 /* Get a FUNCTION_DECL for the init function for the thread_local 2853 variable VAR. The init function will be an alias to the function 2854 that initializes all the non-local TLS variables in the translation 2855 unit. The init function is only used by the wrapper function. */ 2856 2857 static tree 2858 get_tls_init_fn (tree var) 2859 { 2860 /* Only C++11 TLS vars need this init fn. */ 2861 if (!var_needs_tls_wrapper (var)) 2862 return NULL_TREE; 2863 2864 /* If -fno-extern-tls-init, assume that we don't need to call 2865 a tls init function for a variable defined in another TU. */ 2866 if (!flag_extern_tls_init && DECL_EXTERNAL (var)) 2867 return NULL_TREE; 2868 2869 #ifdef ASM_OUTPUT_DEF 2870 /* If the variable is internal, or if we can't generate aliases, 2871 call the local init function directly. */ 2872 if (!TREE_PUBLIC (var)) 2873 #endif 2874 return get_local_tls_init_fn (); 2875 2876 tree sname = mangle_tls_init_fn (var); 2877 tree fn = IDENTIFIER_GLOBAL_VALUE (sname); 2878 if (!fn) 2879 { 2880 fn = build_lang_decl (FUNCTION_DECL, sname, 2881 build_function_type (void_type_node, 2882 void_list_node)); 2883 SET_DECL_LANGUAGE (fn, lang_c); 2884 TREE_PUBLIC (fn) = TREE_PUBLIC (var); 2885 DECL_ARTIFICIAL (fn) = true; 2886 DECL_COMDAT (fn) = DECL_COMDAT (var); 2887 DECL_EXTERNAL (fn) = DECL_EXTERNAL (var); 2888 if (DECL_ONE_ONLY (var)) 2889 make_decl_one_only (fn, cxx_comdat_group (fn)); 2890 if (TREE_PUBLIC (var)) 2891 { 2892 tree obtype = strip_array_types (non_reference (TREE_TYPE (var))); 2893 /* If the variable is defined somewhere else and might have static 2894 initialization, make the init function a weak reference. */ 2895 if ((!TYPE_NEEDS_CONSTRUCTING (obtype) 2896 || TYPE_HAS_CONSTEXPR_CTOR (obtype)) 2897 && TYPE_HAS_TRIVIAL_DESTRUCTOR (obtype) 2898 && DECL_EXTERNAL (var)) 2899 declare_weak (fn); 2900 else 2901 DECL_WEAK (fn) = DECL_WEAK (var); 2902 } 2903 DECL_VISIBILITY (fn) = DECL_VISIBILITY (var); 2904 DECL_VISIBILITY_SPECIFIED (fn) = DECL_VISIBILITY_SPECIFIED (var); 2905 DECL_DLLIMPORT_P (fn) = DECL_DLLIMPORT_P (var); 2906 DECL_IGNORED_P (fn) = 1; 2907 mark_used (fn); 2908 2909 DECL_BEFRIENDING_CLASSES (fn) = var; 2910 2911 SET_IDENTIFIER_GLOBAL_VALUE (sname, fn); 2912 } 2913 return fn; 2914 } 2915 2916 /* Get a FUNCTION_DECL for the init wrapper function for the thread_local 2917 variable VAR. The wrapper function calls the init function (if any) for 2918 VAR and then returns a reference to VAR. The wrapper function is used 2919 in place of VAR everywhere VAR is mentioned. */ 2920 2921 tree 2922 get_tls_wrapper_fn (tree var) 2923 { 2924 /* Only C++11 TLS vars need this wrapper fn. */ 2925 if (!var_needs_tls_wrapper (var)) 2926 return NULL_TREE; 2927 2928 tree sname = mangle_tls_wrapper_fn (var); 2929 tree fn = IDENTIFIER_GLOBAL_VALUE (sname); 2930 if (!fn) 2931 { 2932 /* A named rvalue reference is an lvalue, so the wrapper should 2933 always return an lvalue reference. */ 2934 tree type = non_reference (TREE_TYPE (var)); 2935 type = build_reference_type (type); 2936 tree fntype = build_function_type (type, void_list_node); 2937 fn = build_lang_decl (FUNCTION_DECL, sname, fntype); 2938 SET_DECL_LANGUAGE (fn, lang_c); 2939 TREE_PUBLIC (fn) = TREE_PUBLIC (var); 2940 DECL_ARTIFICIAL (fn) = true; 2941 DECL_IGNORED_P (fn) = 1; 2942 /* The wrapper is inline and emitted everywhere var is used. */ 2943 DECL_DECLARED_INLINE_P (fn) = true; 2944 if (TREE_PUBLIC (var)) 2945 { 2946 comdat_linkage (fn); 2947 #ifdef HAVE_GAS_HIDDEN 2948 /* Make the wrapper bind locally; there's no reason to share 2949 the wrapper between multiple shared objects. */ 2950 DECL_VISIBILITY (fn) = VISIBILITY_INTERNAL; 2951 DECL_VISIBILITY_SPECIFIED (fn) = true; 2952 #endif 2953 } 2954 if (!TREE_PUBLIC (fn)) 2955 DECL_INTERFACE_KNOWN (fn) = true; 2956 mark_used (fn); 2957 note_vague_linkage_fn (fn); 2958 2959 #if 0 2960 /* We want CSE to commonize calls to the wrapper, but marking it as 2961 pure is unsafe since it has side-effects. I guess we need a new 2962 ECF flag even weaker than ECF_PURE. FIXME! */ 2963 DECL_PURE_P (fn) = true; 2964 #endif 2965 2966 DECL_BEFRIENDING_CLASSES (fn) = var; 2967 2968 SET_IDENTIFIER_GLOBAL_VALUE (sname, fn); 2969 } 2970 return fn; 2971 } 2972 2973 /* At EOF, generate the definition for the TLS wrapper function FN: 2974 2975 T& var_wrapper() { 2976 if (init_fn) init_fn(); 2977 return var; 2978 } */ 2979 2980 static void 2981 generate_tls_wrapper (tree fn) 2982 { 2983 tree var = DECL_BEFRIENDING_CLASSES (fn); 2984 2985 start_preparsed_function (fn, NULL_TREE, SF_DEFAULT | SF_PRE_PARSED); 2986 tree body = begin_function_body (); 2987 /* Only call the init fn if there might be one. */ 2988 if (tree init_fn = get_tls_init_fn (var)) 2989 { 2990 tree if_stmt = NULL_TREE; 2991 /* If init_fn is a weakref, make sure it exists before calling. */ 2992 if (lookup_attribute ("weak", DECL_ATTRIBUTES (init_fn))) 2993 { 2994 if_stmt = begin_if_stmt (); 2995 tree addr = cp_build_addr_expr (init_fn, tf_warning_or_error); 2996 tree cond = cp_build_binary_op (DECL_SOURCE_LOCATION (var), 2997 NE_EXPR, addr, nullptr_node, 2998 tf_warning_or_error); 2999 finish_if_stmt_cond (cond, if_stmt); 3000 } 3001 finish_expr_stmt (build_cxx_call 3002 (init_fn, 0, NULL, tf_warning_or_error)); 3003 if (if_stmt) 3004 { 3005 finish_then_clause (if_stmt); 3006 finish_if_stmt (if_stmt); 3007 } 3008 } 3009 else 3010 /* If there's no initialization, the wrapper is a constant function. */ 3011 TREE_READONLY (fn) = true; 3012 finish_return_stmt (convert_from_reference (var)); 3013 finish_function_body (body); 3014 expand_or_defer_fn (finish_function (0)); 3015 } 3016 3017 /* Start the process of running a particular set of global constructors 3018 or destructors. Subroutine of do_[cd]tors. */ 3019 3020 static tree 3021 start_objects (int method_type, int initp) 3022 { 3023 tree body; 3024 tree fndecl; 3025 char type[14]; 3026 3027 /* Make ctor or dtor function. METHOD_TYPE may be 'I' or 'D'. */ 3028 3029 if (initp != DEFAULT_INIT_PRIORITY) 3030 { 3031 char joiner; 3032 3033 #ifdef JOINER 3034 joiner = JOINER; 3035 #else 3036 joiner = '_'; 3037 #endif 3038 3039 sprintf (type, "sub_%c%c%.5u", method_type, joiner, initp); 3040 } 3041 else 3042 sprintf (type, "sub_%c", method_type); 3043 3044 fndecl = build_lang_decl (FUNCTION_DECL, 3045 get_file_function_name (type), 3046 build_function_type_list (void_type_node, 3047 NULL_TREE)); 3048 start_preparsed_function (fndecl, /*attrs=*/NULL_TREE, SF_PRE_PARSED); 3049 3050 TREE_PUBLIC (current_function_decl) = 0; 3051 3052 /* Mark as artificial because it's not explicitly in the user's 3053 source code. */ 3054 DECL_ARTIFICIAL (current_function_decl) = 1; 3055 3056 /* Mark this declaration as used to avoid spurious warnings. */ 3057 TREE_USED (current_function_decl) = 1; 3058 3059 /* Mark this function as a global constructor or destructor. */ 3060 if (method_type == 'I') 3061 DECL_GLOBAL_CTOR_P (current_function_decl) = 1; 3062 else 3063 DECL_GLOBAL_DTOR_P (current_function_decl) = 1; 3064 3065 body = begin_compound_stmt (BCS_FN_BODY); 3066 3067 return body; 3068 } 3069 3070 /* Finish the process of running a particular set of global constructors 3071 or destructors. Subroutine of do_[cd]tors. */ 3072 3073 static void 3074 finish_objects (int method_type, int initp, tree body) 3075 { 3076 tree fn; 3077 3078 /* Finish up. */ 3079 finish_compound_stmt (body); 3080 fn = finish_function (0); 3081 3082 if (method_type == 'I') 3083 { 3084 DECL_STATIC_CONSTRUCTOR (fn) = 1; 3085 decl_init_priority_insert (fn, initp); 3086 } 3087 else 3088 { 3089 DECL_STATIC_DESTRUCTOR (fn) = 1; 3090 decl_fini_priority_insert (fn, initp); 3091 } 3092 3093 expand_or_defer_fn (fn); 3094 } 3095 3096 /* The names of the parameters to the function created to handle 3097 initializations and destructions for objects with static storage 3098 duration. */ 3099 #define INITIALIZE_P_IDENTIFIER "__initialize_p" 3100 #define PRIORITY_IDENTIFIER "__priority" 3101 3102 /* The name of the function we create to handle initializations and 3103 destructions for objects with static storage duration. */ 3104 #define SSDF_IDENTIFIER "__static_initialization_and_destruction" 3105 3106 /* The declaration for the __INITIALIZE_P argument. */ 3107 static GTY(()) tree initialize_p_decl; 3108 3109 /* The declaration for the __PRIORITY argument. */ 3110 static GTY(()) tree priority_decl; 3111 3112 /* The declaration for the static storage duration function. */ 3113 static GTY(()) tree ssdf_decl; 3114 3115 /* All the static storage duration functions created in this 3116 translation unit. */ 3117 static GTY(()) vec<tree, va_gc> *ssdf_decls; 3118 3119 /* A map from priority levels to information about that priority 3120 level. There may be many such levels, so efficient lookup is 3121 important. */ 3122 static splay_tree priority_info_map; 3123 3124 /* Begins the generation of the function that will handle all 3125 initialization and destruction of objects with static storage 3126 duration. The function generated takes two parameters of type 3127 `int': __INITIALIZE_P and __PRIORITY. If __INITIALIZE_P is 3128 nonzero, it performs initializations. Otherwise, it performs 3129 destructions. It only performs those initializations or 3130 destructions with the indicated __PRIORITY. The generated function 3131 returns no value. 3132 3133 It is assumed that this function will only be called once per 3134 translation unit. */ 3135 3136 static tree 3137 start_static_storage_duration_function (unsigned count) 3138 { 3139 tree type; 3140 tree body; 3141 char id[sizeof (SSDF_IDENTIFIER) + 1 /* '\0' */ + 32]; 3142 3143 /* Create the identifier for this function. It will be of the form 3144 SSDF_IDENTIFIER_<number>. */ 3145 sprintf (id, "%s_%u", SSDF_IDENTIFIER, count); 3146 3147 type = build_function_type_list (void_type_node, 3148 integer_type_node, integer_type_node, 3149 NULL_TREE); 3150 3151 /* Create the FUNCTION_DECL itself. */ 3152 ssdf_decl = build_lang_decl (FUNCTION_DECL, 3153 get_identifier (id), 3154 type); 3155 TREE_PUBLIC (ssdf_decl) = 0; 3156 DECL_ARTIFICIAL (ssdf_decl) = 1; 3157 3158 /* Put this function in the list of functions to be called from the 3159 static constructors and destructors. */ 3160 if (!ssdf_decls) 3161 { 3162 vec_alloc (ssdf_decls, 32); 3163 3164 /* Take this opportunity to initialize the map from priority 3165 numbers to information about that priority level. */ 3166 priority_info_map = splay_tree_new (splay_tree_compare_ints, 3167 /*delete_key_fn=*/0, 3168 /*delete_value_fn=*/ 3169 (splay_tree_delete_value_fn) &free); 3170 3171 /* We always need to generate functions for the 3172 DEFAULT_INIT_PRIORITY so enter it now. That way when we walk 3173 priorities later, we'll be sure to find the 3174 DEFAULT_INIT_PRIORITY. */ 3175 get_priority_info (DEFAULT_INIT_PRIORITY); 3176 } 3177 3178 vec_safe_push (ssdf_decls, ssdf_decl); 3179 3180 /* Create the argument list. */ 3181 initialize_p_decl = cp_build_parm_decl 3182 (get_identifier (INITIALIZE_P_IDENTIFIER), integer_type_node); 3183 DECL_CONTEXT (initialize_p_decl) = ssdf_decl; 3184 TREE_USED (initialize_p_decl) = 1; 3185 priority_decl = cp_build_parm_decl 3186 (get_identifier (PRIORITY_IDENTIFIER), integer_type_node); 3187 DECL_CONTEXT (priority_decl) = ssdf_decl; 3188 TREE_USED (priority_decl) = 1; 3189 3190 DECL_CHAIN (initialize_p_decl) = priority_decl; 3191 DECL_ARGUMENTS (ssdf_decl) = initialize_p_decl; 3192 3193 /* Put the function in the global scope. */ 3194 pushdecl (ssdf_decl); 3195 3196 /* Start the function itself. This is equivalent to declaring the 3197 function as: 3198 3199 static void __ssdf (int __initialize_p, init __priority_p); 3200 3201 It is static because we only need to call this function from the 3202 various constructor and destructor functions for this module. */ 3203 start_preparsed_function (ssdf_decl, 3204 /*attrs=*/NULL_TREE, 3205 SF_PRE_PARSED); 3206 3207 /* Set up the scope of the outermost block in the function. */ 3208 body = begin_compound_stmt (BCS_FN_BODY); 3209 3210 return body; 3211 } 3212 3213 /* Finish the generation of the function which performs initialization 3214 and destruction of objects with static storage duration. After 3215 this point, no more such objects can be created. */ 3216 3217 static void 3218 finish_static_storage_duration_function (tree body) 3219 { 3220 /* Close out the function. */ 3221 finish_compound_stmt (body); 3222 expand_or_defer_fn (finish_function (0)); 3223 } 3224 3225 /* Return the information about the indicated PRIORITY level. If no 3226 code to handle this level has yet been generated, generate the 3227 appropriate prologue. */ 3228 3229 static priority_info 3230 get_priority_info (int priority) 3231 { 3232 priority_info pi; 3233 splay_tree_node n; 3234 3235 n = splay_tree_lookup (priority_info_map, 3236 (splay_tree_key) priority); 3237 if (!n) 3238 { 3239 /* Create a new priority information structure, and insert it 3240 into the map. */ 3241 pi = XNEW (struct priority_info_s); 3242 pi->initializations_p = 0; 3243 pi->destructions_p = 0; 3244 splay_tree_insert (priority_info_map, 3245 (splay_tree_key) priority, 3246 (splay_tree_value) pi); 3247 } 3248 else 3249 pi = (priority_info) n->value; 3250 3251 return pi; 3252 } 3253 3254 /* The effective initialization priority of a DECL. */ 3255 3256 #define DECL_EFFECTIVE_INIT_PRIORITY(decl) \ 3257 ((!DECL_HAS_INIT_PRIORITY_P (decl) || DECL_INIT_PRIORITY (decl) == 0) \ 3258 ? DEFAULT_INIT_PRIORITY : DECL_INIT_PRIORITY (decl)) 3259 3260 /* Whether a DECL needs a guard to protect it against multiple 3261 initialization. */ 3262 3263 #define NEEDS_GUARD_P(decl) (TREE_PUBLIC (decl) && (DECL_COMMON (decl) \ 3264 || DECL_ONE_ONLY (decl) \ 3265 || DECL_WEAK (decl))) 3266 3267 /* Called from one_static_initialization_or_destruction(), 3268 via walk_tree. 3269 Walks the initializer list of a global variable and looks for 3270 temporary variables (DECL_NAME() == NULL and DECL_ARTIFICIAL != 0) 3271 and that have their DECL_CONTEXT() == NULL. 3272 For each such temporary variable, set their DECL_CONTEXT() to 3273 the current function. This is necessary because otherwise 3274 some optimizers (enabled by -O2 -fprofile-arcs) might crash 3275 when trying to refer to a temporary variable that does not have 3276 it's DECL_CONTECT() properly set. */ 3277 static tree 3278 fix_temporary_vars_context_r (tree *node, 3279 int * /*unused*/, 3280 void * /*unused1*/) 3281 { 3282 gcc_assert (current_function_decl); 3283 3284 if (TREE_CODE (*node) == BIND_EXPR) 3285 { 3286 tree var; 3287 3288 for (var = BIND_EXPR_VARS (*node); var; var = DECL_CHAIN (var)) 3289 if (TREE_CODE (var) == VAR_DECL 3290 && !DECL_NAME (var) 3291 && DECL_ARTIFICIAL (var) 3292 && !DECL_CONTEXT (var)) 3293 DECL_CONTEXT (var) = current_function_decl; 3294 } 3295 3296 return NULL_TREE; 3297 } 3298 3299 /* Set up to handle the initialization or destruction of DECL. If 3300 INITP is nonzero, we are initializing the variable. Otherwise, we 3301 are destroying it. */ 3302 3303 static void 3304 one_static_initialization_or_destruction (tree decl, tree init, bool initp) 3305 { 3306 tree guard_if_stmt = NULL_TREE; 3307 tree guard; 3308 3309 /* If we are supposed to destruct and there's a trivial destructor, 3310 nothing has to be done. */ 3311 if (!initp 3312 && TYPE_HAS_TRIVIAL_DESTRUCTOR (TREE_TYPE (decl))) 3313 return; 3314 3315 /* Trick the compiler into thinking we are at the file and line 3316 where DECL was declared so that error-messages make sense, and so 3317 that the debugger will show somewhat sensible file and line 3318 information. */ 3319 input_location = DECL_SOURCE_LOCATION (decl); 3320 3321 /* Make sure temporary variables in the initialiser all have 3322 their DECL_CONTEXT() set to a value different from NULL_TREE. 3323 This can happen when global variables initialisers are built. 3324 In that case, the DECL_CONTEXT() of the global variables _AND_ of all 3325 the temporary variables that might have been generated in the 3326 accompagning initialisers is NULL_TREE, meaning the variables have been 3327 declared in the global namespace. 3328 What we want to do here is to fix that and make sure the DECL_CONTEXT() 3329 of the temporaries are set to the current function decl. */ 3330 cp_walk_tree_without_duplicates (&init, 3331 fix_temporary_vars_context_r, 3332 NULL); 3333 3334 /* Because of: 3335 3336 [class.access.spec] 3337 3338 Access control for implicit calls to the constructors, 3339 the conversion functions, or the destructor called to 3340 create and destroy a static data member is performed as 3341 if these calls appeared in the scope of the member's 3342 class. 3343 3344 we pretend we are in a static member function of the class of 3345 which the DECL is a member. */ 3346 if (member_p (decl)) 3347 { 3348 DECL_CONTEXT (current_function_decl) = DECL_CONTEXT (decl); 3349 DECL_STATIC_FUNCTION_P (current_function_decl) = 1; 3350 } 3351 3352 /* Assume we don't need a guard. */ 3353 guard = NULL_TREE; 3354 /* We need a guard if this is an object with external linkage that 3355 might be initialized in more than one place. (For example, a 3356 static data member of a template, when the data member requires 3357 construction.) */ 3358 if (NEEDS_GUARD_P (decl)) 3359 { 3360 tree guard_cond; 3361 3362 guard = get_guard (decl); 3363 3364 /* When using __cxa_atexit, we just check the GUARD as we would 3365 for a local static. */ 3366 if (flag_use_cxa_atexit) 3367 { 3368 /* When using __cxa_atexit, we never try to destroy 3369 anything from a static destructor. */ 3370 gcc_assert (initp); 3371 guard_cond = get_guard_cond (guard); 3372 } 3373 /* If we don't have __cxa_atexit, then we will be running 3374 destructors from .fini sections, or their equivalents. So, 3375 we need to know how many times we've tried to initialize this 3376 object. We do initializations only if the GUARD is zero, 3377 i.e., if we are the first to initialize the variable. We do 3378 destructions only if the GUARD is one, i.e., if we are the 3379 last to destroy the variable. */ 3380 else if (initp) 3381 guard_cond 3382 = cp_build_binary_op (input_location, 3383 EQ_EXPR, 3384 cp_build_unary_op (PREINCREMENT_EXPR, 3385 guard, 3386 /*noconvert=*/1, 3387 tf_warning_or_error), 3388 integer_one_node, 3389 tf_warning_or_error); 3390 else 3391 guard_cond 3392 = cp_build_binary_op (input_location, 3393 EQ_EXPR, 3394 cp_build_unary_op (PREDECREMENT_EXPR, 3395 guard, 3396 /*noconvert=*/1, 3397 tf_warning_or_error), 3398 integer_zero_node, 3399 tf_warning_or_error); 3400 3401 guard_if_stmt = begin_if_stmt (); 3402 finish_if_stmt_cond (guard_cond, guard_if_stmt); 3403 } 3404 3405 3406 /* If we're using __cxa_atexit, we have not already set the GUARD, 3407 so we must do so now. */ 3408 if (guard && initp && flag_use_cxa_atexit) 3409 finish_expr_stmt (set_guard (guard)); 3410 3411 /* Perform the initialization or destruction. */ 3412 if (initp) 3413 { 3414 if (init) 3415 finish_expr_stmt (init); 3416 3417 /* If we're using __cxa_atexit, register a function that calls the 3418 destructor for the object. */ 3419 if (flag_use_cxa_atexit) 3420 finish_expr_stmt (register_dtor_fn (decl)); 3421 } 3422 else 3423 finish_expr_stmt (build_cleanup (decl)); 3424 3425 /* Finish the guard if-stmt, if necessary. */ 3426 if (guard) 3427 { 3428 finish_then_clause (guard_if_stmt); 3429 finish_if_stmt (guard_if_stmt); 3430 } 3431 3432 /* Now that we're done with DECL we don't need to pretend to be a 3433 member of its class any longer. */ 3434 DECL_CONTEXT (current_function_decl) = NULL_TREE; 3435 DECL_STATIC_FUNCTION_P (current_function_decl) = 0; 3436 } 3437 3438 /* Generate code to do the initialization or destruction of the decls in VARS, 3439 a TREE_LIST of VAR_DECL with static storage duration. 3440 Whether initialization or destruction is performed is specified by INITP. */ 3441 3442 static void 3443 do_static_initialization_or_destruction (tree vars, bool initp) 3444 { 3445 tree node, init_if_stmt, cond; 3446 3447 /* Build the outer if-stmt to check for initialization or destruction. */ 3448 init_if_stmt = begin_if_stmt (); 3449 cond = initp ? integer_one_node : integer_zero_node; 3450 cond = cp_build_binary_op (input_location, 3451 EQ_EXPR, 3452 initialize_p_decl, 3453 cond, 3454 tf_warning_or_error); 3455 finish_if_stmt_cond (cond, init_if_stmt); 3456 3457 node = vars; 3458 do { 3459 tree decl = TREE_VALUE (node); 3460 tree priority_if_stmt; 3461 int priority; 3462 priority_info pi; 3463 3464 /* If we don't need a destructor, there's nothing to do. Avoid 3465 creating a possibly empty if-stmt. */ 3466 if (!initp && TYPE_HAS_TRIVIAL_DESTRUCTOR (TREE_TYPE (decl))) 3467 { 3468 node = TREE_CHAIN (node); 3469 continue; 3470 } 3471 3472 /* Remember that we had an initialization or finalization at this 3473 priority. */ 3474 priority = DECL_EFFECTIVE_INIT_PRIORITY (decl); 3475 pi = get_priority_info (priority); 3476 if (initp) 3477 pi->initializations_p = 1; 3478 else 3479 pi->destructions_p = 1; 3480 3481 /* Conditionalize this initialization on being in the right priority 3482 and being initializing/finalizing appropriately. */ 3483 priority_if_stmt = begin_if_stmt (); 3484 cond = cp_build_binary_op (input_location, 3485 EQ_EXPR, 3486 priority_decl, 3487 build_int_cst (NULL_TREE, priority), 3488 tf_warning_or_error); 3489 finish_if_stmt_cond (cond, priority_if_stmt); 3490 3491 /* Process initializers with same priority. */ 3492 for (; node 3493 && DECL_EFFECTIVE_INIT_PRIORITY (TREE_VALUE (node)) == priority; 3494 node = TREE_CHAIN (node)) 3495 /* Do one initialization or destruction. */ 3496 one_static_initialization_or_destruction (TREE_VALUE (node), 3497 TREE_PURPOSE (node), initp); 3498 3499 /* Finish up the priority if-stmt body. */ 3500 finish_then_clause (priority_if_stmt); 3501 finish_if_stmt (priority_if_stmt); 3502 3503 } while (node); 3504 3505 /* Finish up the init/destruct if-stmt body. */ 3506 finish_then_clause (init_if_stmt); 3507 finish_if_stmt (init_if_stmt); 3508 } 3509 3510 /* VARS is a list of variables with static storage duration which may 3511 need initialization and/or finalization. Remove those variables 3512 that don't really need to be initialized or finalized, and return 3513 the resulting list. The order in which the variables appear in 3514 VARS is in reverse order of the order in which they should actually 3515 be initialized. The list we return is in the unreversed order; 3516 i.e., the first variable should be initialized first. */ 3517 3518 static tree 3519 prune_vars_needing_no_initialization (tree *vars) 3520 { 3521 tree *var = vars; 3522 tree result = NULL_TREE; 3523 3524 while (*var) 3525 { 3526 tree t = *var; 3527 tree decl = TREE_VALUE (t); 3528 tree init = TREE_PURPOSE (t); 3529 3530 /* Deal gracefully with error. */ 3531 if (decl == error_mark_node) 3532 { 3533 var = &TREE_CHAIN (t); 3534 continue; 3535 } 3536 3537 /* The only things that can be initialized are variables. */ 3538 gcc_assert (TREE_CODE (decl) == VAR_DECL); 3539 3540 /* If this object is not defined, we don't need to do anything 3541 here. */ 3542 if (DECL_EXTERNAL (decl)) 3543 { 3544 var = &TREE_CHAIN (t); 3545 continue; 3546 } 3547 3548 /* Also, if the initializer already contains errors, we can bail 3549 out now. */ 3550 if (init && TREE_CODE (init) == TREE_LIST 3551 && value_member (error_mark_node, init)) 3552 { 3553 var = &TREE_CHAIN (t); 3554 continue; 3555 } 3556 3557 /* This variable is going to need initialization and/or 3558 finalization, so we add it to the list. */ 3559 *var = TREE_CHAIN (t); 3560 TREE_CHAIN (t) = result; 3561 result = t; 3562 } 3563 3564 return result; 3565 } 3566 3567 /* Make sure we have told the back end about all the variables in 3568 VARS. */ 3569 3570 static void 3571 write_out_vars (tree vars) 3572 { 3573 tree v; 3574 3575 for (v = vars; v; v = TREE_CHAIN (v)) 3576 { 3577 tree var = TREE_VALUE (v); 3578 if (!var_finalized_p (var)) 3579 { 3580 import_export_decl (var); 3581 rest_of_decl_compilation (var, 1, 1); 3582 } 3583 } 3584 } 3585 3586 /* Generate a static constructor (if CONSTRUCTOR_P) or destructor 3587 (otherwise) that will initialize all global objects with static 3588 storage duration having the indicated PRIORITY. */ 3589 3590 static void 3591 generate_ctor_or_dtor_function (bool constructor_p, int priority, 3592 location_t *locus) 3593 { 3594 char function_key; 3595 tree fndecl; 3596 tree body; 3597 size_t i; 3598 3599 input_location = *locus; 3600 /* ??? */ 3601 /* Was: locus->line++; */ 3602 3603 /* We use `I' to indicate initialization and `D' to indicate 3604 destruction. */ 3605 function_key = constructor_p ? 'I' : 'D'; 3606 3607 /* We emit the function lazily, to avoid generating empty 3608 global constructors and destructors. */ 3609 body = NULL_TREE; 3610 3611 /* For Objective-C++, we may need to initialize metadata found in this module. 3612 This must be done _before_ any other static initializations. */ 3613 if (c_dialect_objc () && (priority == DEFAULT_INIT_PRIORITY) 3614 && constructor_p && objc_static_init_needed_p ()) 3615 { 3616 body = start_objects (function_key, priority); 3617 objc_generate_static_init_call (NULL_TREE); 3618 } 3619 3620 /* Call the static storage duration function with appropriate 3621 arguments. */ 3622 FOR_EACH_VEC_SAFE_ELT (ssdf_decls, i, fndecl) 3623 { 3624 /* Calls to pure or const functions will expand to nothing. */ 3625 if (! (flags_from_decl_or_type (fndecl) & (ECF_CONST | ECF_PURE))) 3626 { 3627 tree call; 3628 3629 if (! body) 3630 body = start_objects (function_key, priority); 3631 3632 call = cp_build_function_call_nary (fndecl, tf_warning_or_error, 3633 build_int_cst (NULL_TREE, 3634 constructor_p), 3635 build_int_cst (NULL_TREE, 3636 priority), 3637 NULL_TREE); 3638 finish_expr_stmt (call); 3639 } 3640 } 3641 3642 /* Close out the function. */ 3643 if (body) 3644 finish_objects (function_key, priority, body); 3645 } 3646 3647 /* Generate constructor and destructor functions for the priority 3648 indicated by N. */ 3649 3650 static int 3651 generate_ctor_and_dtor_functions_for_priority (splay_tree_node n, void * data) 3652 { 3653 location_t *locus = (location_t *) data; 3654 int priority = (int) n->key; 3655 priority_info pi = (priority_info) n->value; 3656 3657 /* Generate the functions themselves, but only if they are really 3658 needed. */ 3659 if (pi->initializations_p) 3660 generate_ctor_or_dtor_function (/*constructor_p=*/true, priority, locus); 3661 if (pi->destructions_p) 3662 generate_ctor_or_dtor_function (/*constructor_p=*/false, priority, locus); 3663 3664 /* Keep iterating. */ 3665 return 0; 3666 } 3667 3668 /* Java requires that we be able to reference a local address for a 3669 method, and not be confused by PLT entries. If hidden aliases are 3670 supported, collect and return all the functions for which we should 3671 emit a hidden alias. */ 3672 3673 static struct pointer_set_t * 3674 collect_candidates_for_java_method_aliases (void) 3675 { 3676 struct cgraph_node *node; 3677 struct pointer_set_t *candidates = NULL; 3678 3679 #ifndef HAVE_GAS_HIDDEN 3680 return candidates; 3681 #endif 3682 3683 FOR_EACH_FUNCTION (node) 3684 { 3685 tree fndecl = node->symbol.decl; 3686 3687 if (DECL_CONTEXT (fndecl) 3688 && TYPE_P (DECL_CONTEXT (fndecl)) 3689 && TYPE_FOR_JAVA (DECL_CONTEXT (fndecl)) 3690 && TARGET_USE_LOCAL_THUNK_ALIAS_P (fndecl)) 3691 { 3692 if (candidates == NULL) 3693 candidates = pointer_set_create (); 3694 pointer_set_insert (candidates, fndecl); 3695 } 3696 } 3697 3698 return candidates; 3699 } 3700 3701 3702 /* Java requires that we be able to reference a local address for a 3703 method, and not be confused by PLT entries. If hidden aliases are 3704 supported, emit one for each java function that we've emitted. 3705 CANDIDATES is the set of FUNCTION_DECLs that were gathered 3706 by collect_candidates_for_java_method_aliases. */ 3707 3708 static void 3709 build_java_method_aliases (struct pointer_set_t *candidates) 3710 { 3711 struct cgraph_node *node; 3712 3713 #ifndef HAVE_GAS_HIDDEN 3714 return; 3715 #endif 3716 3717 FOR_EACH_FUNCTION (node) 3718 { 3719 tree fndecl = node->symbol.decl; 3720 3721 if (TREE_ASM_WRITTEN (fndecl) 3722 && pointer_set_contains (candidates, fndecl)) 3723 { 3724 /* Mangle the name in a predictable way; we need to reference 3725 this from a java compiled object file. */ 3726 tree oid, nid, alias; 3727 const char *oname; 3728 char *nname; 3729 3730 oid = DECL_ASSEMBLER_NAME (fndecl); 3731 oname = IDENTIFIER_POINTER (oid); 3732 gcc_assert (oname[0] == '_' && oname[1] == 'Z'); 3733 nname = ACONCAT (("_ZGA", oname+2, NULL)); 3734 nid = get_identifier (nname); 3735 3736 alias = make_alias_for (fndecl, nid); 3737 TREE_PUBLIC (alias) = 1; 3738 DECL_VISIBILITY (alias) = VISIBILITY_HIDDEN; 3739 3740 assemble_alias (alias, oid); 3741 } 3742 } 3743 } 3744 3745 /* Return C++ property of T, based on given operation OP. */ 3746 3747 static int 3748 cpp_check (tree t, cpp_operation op) 3749 { 3750 switch (op) 3751 { 3752 case IS_ABSTRACT: 3753 return DECL_PURE_VIRTUAL_P (t); 3754 case IS_CONSTRUCTOR: 3755 return DECL_CONSTRUCTOR_P (t); 3756 case IS_DESTRUCTOR: 3757 return DECL_DESTRUCTOR_P (t); 3758 case IS_COPY_CONSTRUCTOR: 3759 return DECL_COPY_CONSTRUCTOR_P (t); 3760 case IS_TEMPLATE: 3761 return TREE_CODE (t) == TEMPLATE_DECL; 3762 default: 3763 return 0; 3764 } 3765 } 3766 3767 /* Collect source file references recursively, starting from NAMESPC. */ 3768 3769 static void 3770 collect_source_refs (tree namespc) 3771 { 3772 tree t; 3773 3774 if (!namespc) 3775 return; 3776 3777 /* Iterate over names in this name space. */ 3778 for (t = NAMESPACE_LEVEL (namespc)->names; t; t = TREE_CHAIN (t)) 3779 if (!DECL_IS_BUILTIN (t) ) 3780 collect_source_ref (DECL_SOURCE_FILE (t)); 3781 3782 /* Dump siblings, if any */ 3783 collect_source_refs (TREE_CHAIN (namespc)); 3784 3785 /* Dump children, if any */ 3786 collect_source_refs (NAMESPACE_LEVEL (namespc)->namespaces); 3787 } 3788 3789 /* Collect decls relevant to SOURCE_FILE from all namespaces recursively, 3790 starting from NAMESPC. */ 3791 3792 static void 3793 collect_ada_namespace (tree namespc, const char *source_file) 3794 { 3795 if (!namespc) 3796 return; 3797 3798 /* Collect decls from this namespace */ 3799 collect_ada_nodes (NAMESPACE_LEVEL (namespc)->names, source_file); 3800 3801 /* Collect siblings, if any */ 3802 collect_ada_namespace (TREE_CHAIN (namespc), source_file); 3803 3804 /* Collect children, if any */ 3805 collect_ada_namespace (NAMESPACE_LEVEL (namespc)->namespaces, source_file); 3806 } 3807 3808 /* Returns true iff there is a definition available for variable or 3809 function DECL. */ 3810 3811 static bool 3812 decl_defined_p (tree decl) 3813 { 3814 if (TREE_CODE (decl) == FUNCTION_DECL) 3815 return (DECL_INITIAL (decl) != NULL_TREE); 3816 else 3817 { 3818 gcc_assert (TREE_CODE (decl) == VAR_DECL); 3819 return !DECL_EXTERNAL (decl); 3820 } 3821 } 3822 3823 /* Nonzero for a VAR_DECL whose value can be used in a constant expression. 3824 3825 [expr.const] 3826 3827 An integral constant-expression can only involve ... const 3828 variables of integral or enumeration types initialized with 3829 constant expressions ... 3830 3831 C++0x also allows constexpr variables and temporaries initialized 3832 with constant expressions. We handle the former here, but the latter 3833 are just folded away in cxx_eval_constant_expression. 3834 3835 The standard does not require that the expression be non-volatile. 3836 G++ implements the proposed correction in DR 457. */ 3837 3838 bool 3839 decl_constant_var_p (tree decl) 3840 { 3841 if (!decl_maybe_constant_var_p (decl)) 3842 return false; 3843 3844 /* We don't know if a template static data member is initialized with 3845 a constant expression until we instantiate its initializer. Even 3846 in the case of a constexpr variable, we can't treat it as a 3847 constant until its initializer is complete in case it's used in 3848 its own initializer. */ 3849 mark_used (decl); 3850 return DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl); 3851 } 3852 3853 /* Returns true if DECL could be a symbolic constant variable, depending on 3854 its initializer. */ 3855 3856 bool 3857 decl_maybe_constant_var_p (tree decl) 3858 { 3859 tree type = TREE_TYPE (decl); 3860 if (TREE_CODE (decl) != VAR_DECL) 3861 return false; 3862 if (DECL_DECLARED_CONSTEXPR_P (decl)) 3863 return true; 3864 return (CP_TYPE_CONST_NON_VOLATILE_P (type) 3865 && INTEGRAL_OR_ENUMERATION_TYPE_P (type)); 3866 } 3867 3868 /* Complain that DECL uses a type with no linkage but is never defined. */ 3869 3870 static void 3871 no_linkage_error (tree decl) 3872 { 3873 tree t = no_linkage_check (TREE_TYPE (decl), /*relaxed_p=*/false); 3874 if (TYPE_ANONYMOUS_P (t)) 3875 { 3876 permerror (0, "%q+#D, declared using anonymous type, " 3877 "is used but never defined", decl); 3878 if (is_typedef_decl (TYPE_NAME (t))) 3879 permerror (0, "%q+#D does not refer to the unqualified type, " 3880 "so it is not used for linkage", TYPE_NAME (t)); 3881 } 3882 else 3883 permerror (0, "%q+#D, declared using local type %qT, " 3884 "is used but never defined", decl, t); 3885 } 3886 3887 /* Collect declarations from all namespaces relevant to SOURCE_FILE. */ 3888 3889 static void 3890 collect_all_refs (const char *source_file) 3891 { 3892 collect_ada_namespace (global_namespace, source_file); 3893 } 3894 3895 /* Clear DECL_EXTERNAL for NODE. */ 3896 3897 static bool 3898 clear_decl_external (struct cgraph_node *node, void * /*data*/) 3899 { 3900 DECL_EXTERNAL (node->symbol.decl) = 0; 3901 return false; 3902 } 3903 3904 /* Build up the function to run dynamic initializers for thread_local 3905 variables in this translation unit and alias the init functions for the 3906 individual variables to it. */ 3907 3908 static void 3909 handle_tls_init (void) 3910 { 3911 tree vars = prune_vars_needing_no_initialization (&tls_aggregates); 3912 if (vars == NULL_TREE) 3913 return; 3914 3915 location_t loc = DECL_SOURCE_LOCATION (TREE_VALUE (vars)); 3916 3917 write_out_vars (vars); 3918 3919 tree guard = build_decl (loc, VAR_DECL, get_identifier ("__tls_guard"), 3920 boolean_type_node); 3921 TREE_PUBLIC (guard) = false; 3922 TREE_STATIC (guard) = true; 3923 DECL_ARTIFICIAL (guard) = true; 3924 DECL_IGNORED_P (guard) = true; 3925 TREE_USED (guard) = true; 3926 DECL_TLS_MODEL (guard) = decl_default_tls_model (guard); 3927 pushdecl_top_level_and_finish (guard, NULL_TREE); 3928 3929 tree fn = get_local_tls_init_fn (); 3930 start_preparsed_function (fn, NULL_TREE, SF_PRE_PARSED); 3931 tree body = begin_function_body (); 3932 tree if_stmt = begin_if_stmt (); 3933 tree cond = cp_build_unary_op (TRUTH_NOT_EXPR, guard, false, 3934 tf_warning_or_error); 3935 finish_if_stmt_cond (cond, if_stmt); 3936 finish_expr_stmt (cp_build_modify_expr (guard, NOP_EXPR, boolean_true_node, 3937 tf_warning_or_error)); 3938 for (; vars; vars = TREE_CHAIN (vars)) 3939 { 3940 tree var = TREE_VALUE (vars); 3941 tree init = TREE_PURPOSE (vars); 3942 one_static_initialization_or_destruction (var, init, true); 3943 3944 #ifdef ASM_OUTPUT_DEF 3945 /* Output init aliases even with -fno-extern-tls-init. */ 3946 if (TREE_PUBLIC (var)) 3947 { 3948 tree single_init_fn = get_tls_init_fn (var); 3949 if (single_init_fn == NULL_TREE) 3950 continue; 3951 cgraph_node *alias 3952 = cgraph_same_body_alias (cgraph_get_create_node (fn), 3953 single_init_fn, fn); 3954 gcc_assert (alias != NULL); 3955 } 3956 #endif 3957 } 3958 3959 finish_then_clause (if_stmt); 3960 finish_if_stmt (if_stmt); 3961 finish_function_body (body); 3962 expand_or_defer_fn (finish_function (0)); 3963 } 3964 3965 /* The entire file is now complete. If requested, dump everything 3966 to a file. */ 3967 3968 static void 3969 dump_tu (void) 3970 { 3971 int flags; 3972 FILE *stream = dump_begin (TDI_tu, &flags); 3973 3974 if (stream) 3975 { 3976 dump_node (global_namespace, flags & ~TDF_SLIM, stream); 3977 dump_end (TDI_tu, stream); 3978 } 3979 } 3980 3981 /* This routine is called at the end of compilation. 3982 Its job is to create all the code needed to initialize and 3983 destroy the global aggregates. We do the destruction 3984 first, since that way we only need to reverse the decls once. */ 3985 3986 void 3987 cp_write_global_declarations (void) 3988 { 3989 tree vars; 3990 bool reconsider; 3991 size_t i; 3992 location_t locus; 3993 unsigned ssdf_count = 0; 3994 int retries = 0; 3995 tree decl; 3996 struct pointer_set_t *candidates; 3997 3998 locus = input_location; 3999 at_eof = 1; 4000 4001 /* Bad parse errors. Just forget about it. */ 4002 if (! global_bindings_p () || current_class_type 4003 || !vec_safe_is_empty (decl_namespace_list)) 4004 return; 4005 4006 /* This is the point to write out a PCH if we're doing that. 4007 In that case we do not want to do anything else. */ 4008 if (pch_file) 4009 { 4010 c_common_write_pch (); 4011 dump_tu (); 4012 return; 4013 } 4014 4015 cgraph_process_same_body_aliases (); 4016 4017 /* Handle -fdump-ada-spec[-slim] */ 4018 if (flag_dump_ada_spec || flag_dump_ada_spec_slim) 4019 { 4020 if (flag_dump_ada_spec_slim) 4021 collect_source_ref (main_input_filename); 4022 else 4023 collect_source_refs (global_namespace); 4024 4025 dump_ada_specs (collect_all_refs, cpp_check); 4026 } 4027 4028 /* FIXME - huh? was input_line -= 1;*/ 4029 4030 timevar_start (TV_PHASE_DEFERRED); 4031 4032 /* We now have to write out all the stuff we put off writing out. 4033 These include: 4034 4035 o Template specializations that we have not yet instantiated, 4036 but which are needed. 4037 o Initialization and destruction for non-local objects with 4038 static storage duration. (Local objects with static storage 4039 duration are initialized when their scope is first entered, 4040 and are cleaned up via atexit.) 4041 o Virtual function tables. 4042 4043 All of these may cause others to be needed. For example, 4044 instantiating one function may cause another to be needed, and 4045 generating the initializer for an object may cause templates to be 4046 instantiated, etc., etc. */ 4047 4048 emit_support_tinfos (); 4049 4050 do 4051 { 4052 tree t; 4053 tree decl; 4054 4055 reconsider = false; 4056 4057 /* If there are templates that we've put off instantiating, do 4058 them now. */ 4059 instantiate_pending_templates (retries); 4060 ggc_collect (); 4061 4062 /* Write out virtual tables as required. Note that writing out 4063 the virtual table for a template class may cause the 4064 instantiation of members of that class. If we write out 4065 vtables then we remove the class from our list so we don't 4066 have to look at it again. */ 4067 4068 while (keyed_classes != NULL_TREE 4069 && maybe_emit_vtables (TREE_VALUE (keyed_classes))) 4070 { 4071 reconsider = true; 4072 keyed_classes = TREE_CHAIN (keyed_classes); 4073 } 4074 4075 t = keyed_classes; 4076 if (t != NULL_TREE) 4077 { 4078 tree next = TREE_CHAIN (t); 4079 4080 while (next) 4081 { 4082 if (maybe_emit_vtables (TREE_VALUE (next))) 4083 { 4084 reconsider = true; 4085 TREE_CHAIN (t) = TREE_CHAIN (next); 4086 } 4087 else 4088 t = next; 4089 4090 next = TREE_CHAIN (t); 4091 } 4092 } 4093 4094 /* Write out needed type info variables. We have to be careful 4095 looping through unemitted decls, because emit_tinfo_decl may 4096 cause other variables to be needed. New elements will be 4097 appended, and we remove from the vector those that actually 4098 get emitted. */ 4099 for (i = unemitted_tinfo_decls->length (); 4100 unemitted_tinfo_decls->iterate (--i, &t);) 4101 if (emit_tinfo_decl (t)) 4102 { 4103 reconsider = true; 4104 unemitted_tinfo_decls->unordered_remove (i); 4105 } 4106 4107 /* The list of objects with static storage duration is built up 4108 in reverse order. We clear STATIC_AGGREGATES so that any new 4109 aggregates added during the initialization of these will be 4110 initialized in the correct order when we next come around the 4111 loop. */ 4112 vars = prune_vars_needing_no_initialization (&static_aggregates); 4113 4114 if (vars) 4115 { 4116 /* We need to start a new initialization function each time 4117 through the loop. That's because we need to know which 4118 vtables have been referenced, and TREE_SYMBOL_REFERENCED 4119 isn't computed until a function is finished, and written 4120 out. That's a deficiency in the back end. When this is 4121 fixed, these initialization functions could all become 4122 inline, with resulting performance improvements. */ 4123 tree ssdf_body; 4124 4125 /* Set the line and file, so that it is obviously not from 4126 the source file. */ 4127 input_location = locus; 4128 ssdf_body = start_static_storage_duration_function (ssdf_count); 4129 4130 /* Make sure the back end knows about all the variables. */ 4131 write_out_vars (vars); 4132 4133 /* First generate code to do all the initializations. */ 4134 if (vars) 4135 do_static_initialization_or_destruction (vars, /*initp=*/true); 4136 4137 /* Then, generate code to do all the destructions. Do these 4138 in reverse order so that the most recently constructed 4139 variable is the first destroyed. If we're using 4140 __cxa_atexit, then we don't need to do this; functions 4141 were registered at initialization time to destroy the 4142 local statics. */ 4143 if (!flag_use_cxa_atexit && vars) 4144 { 4145 vars = nreverse (vars); 4146 do_static_initialization_or_destruction (vars, /*initp=*/false); 4147 } 4148 else 4149 vars = NULL_TREE; 4150 4151 /* Finish up the static storage duration function for this 4152 round. */ 4153 input_location = locus; 4154 finish_static_storage_duration_function (ssdf_body); 4155 4156 /* All those initializations and finalizations might cause 4157 us to need more inline functions, more template 4158 instantiations, etc. */ 4159 reconsider = true; 4160 ssdf_count++; 4161 /* ??? was: locus.line++; */ 4162 } 4163 4164 /* Now do the same for thread_local variables. */ 4165 handle_tls_init (); 4166 4167 /* Go through the set of inline functions whose bodies have not 4168 been emitted yet. If out-of-line copies of these functions 4169 are required, emit them. */ 4170 FOR_EACH_VEC_SAFE_ELT (deferred_fns, i, decl) 4171 { 4172 /* Does it need synthesizing? */ 4173 if (DECL_DEFAULTED_FN (decl) && ! DECL_INITIAL (decl) 4174 && (! DECL_REALLY_EXTERN (decl) || possibly_inlined_p (decl))) 4175 { 4176 /* Even though we're already at the top-level, we push 4177 there again. That way, when we pop back a few lines 4178 hence, all of our state is restored. Otherwise, 4179 finish_function doesn't clean things up, and we end 4180 up with CURRENT_FUNCTION_DECL set. */ 4181 push_to_top_level (); 4182 /* The decl's location will mark where it was first 4183 needed. Save that so synthesize method can indicate 4184 where it was needed from, in case of error */ 4185 input_location = DECL_SOURCE_LOCATION (decl); 4186 synthesize_method (decl); 4187 pop_from_top_level (); 4188 reconsider = true; 4189 } 4190 4191 if (!DECL_INITIAL (decl) && decl_tls_wrapper_p (decl)) 4192 generate_tls_wrapper (decl); 4193 4194 if (!DECL_SAVED_TREE (decl)) 4195 continue; 4196 4197 /* We lie to the back end, pretending that some functions 4198 are not defined when they really are. This keeps these 4199 functions from being put out unnecessarily. But, we must 4200 stop lying when the functions are referenced, or if they 4201 are not comdat since they need to be put out now. If 4202 DECL_INTERFACE_KNOWN, then we have already set 4203 DECL_EXTERNAL appropriately, so there's no need to check 4204 again, and we do not want to clear DECL_EXTERNAL if a 4205 previous call to import_export_decl set it. 4206 4207 This is done in a separate for cycle, because if some 4208 deferred function is contained in another deferred 4209 function later in deferred_fns varray, 4210 rest_of_compilation would skip this function and we 4211 really cannot expand the same function twice. */ 4212 import_export_decl (decl); 4213 if (DECL_NOT_REALLY_EXTERN (decl) 4214 && DECL_INITIAL (decl) 4215 && decl_needed_p (decl)) 4216 { 4217 struct cgraph_node *node, *next; 4218 4219 node = cgraph_get_node (decl); 4220 if (node->same_body_alias) 4221 node = cgraph_alias_aliased_node (node); 4222 4223 cgraph_for_node_and_aliases (node, clear_decl_external, 4224 NULL, true); 4225 /* If we mark !DECL_EXTERNAL one of the symbols in some comdat 4226 group, we need to mark all symbols in the same comdat group 4227 that way. */ 4228 if (node->symbol.same_comdat_group) 4229 for (next = cgraph (node->symbol.same_comdat_group); 4230 next != node; 4231 next = cgraph (next->symbol.same_comdat_group)) 4232 cgraph_for_node_and_aliases (next, clear_decl_external, 4233 NULL, true); 4234 } 4235 4236 /* If we're going to need to write this function out, and 4237 there's already a body for it, create RTL for it now. 4238 (There might be no body if this is a method we haven't 4239 gotten around to synthesizing yet.) */ 4240 if (!DECL_EXTERNAL (decl) 4241 && decl_needed_p (decl) 4242 && !TREE_ASM_WRITTEN (decl) 4243 && !cgraph_get_node (decl)->local.finalized) 4244 { 4245 /* We will output the function; no longer consider it in this 4246 loop. */ 4247 DECL_DEFER_OUTPUT (decl) = 0; 4248 /* Generate RTL for this function now that we know we 4249 need it. */ 4250 expand_or_defer_fn (decl); 4251 /* If we're compiling -fsyntax-only pretend that this 4252 function has been written out so that we don't try to 4253 expand it again. */ 4254 if (flag_syntax_only) 4255 TREE_ASM_WRITTEN (decl) = 1; 4256 reconsider = true; 4257 } 4258 } 4259 4260 if (walk_namespaces (wrapup_globals_for_namespace, /*data=*/0)) 4261 reconsider = true; 4262 4263 /* Static data members are just like namespace-scope globals. */ 4264 FOR_EACH_VEC_SAFE_ELT (pending_statics, i, decl) 4265 { 4266 if (var_finalized_p (decl) || DECL_REALLY_EXTERN (decl) 4267 /* Don't write it out if we haven't seen a definition. */ 4268 || DECL_IN_AGGR_P (decl)) 4269 continue; 4270 import_export_decl (decl); 4271 /* If this static data member is needed, provide it to the 4272 back end. */ 4273 if (DECL_NOT_REALLY_EXTERN (decl) && decl_needed_p (decl)) 4274 DECL_EXTERNAL (decl) = 0; 4275 } 4276 if (vec_safe_length (pending_statics) != 0 4277 && wrapup_global_declarations (pending_statics->address (), 4278 pending_statics->length ())) 4279 reconsider = true; 4280 4281 retries++; 4282 } 4283 while (reconsider); 4284 4285 /* All used inline functions must have a definition at this point. */ 4286 FOR_EACH_VEC_SAFE_ELT (deferred_fns, i, decl) 4287 { 4288 if (/* Check online inline functions that were actually used. */ 4289 DECL_ODR_USED (decl) && DECL_DECLARED_INLINE_P (decl) 4290 /* If the definition actually was available here, then the 4291 fact that the function was not defined merely represents 4292 that for some reason (use of a template repository, 4293 #pragma interface, etc.) we decided not to emit the 4294 definition here. */ 4295 && !DECL_INITIAL (decl) 4296 /* Don't complain if the template was defined. */ 4297 && !(DECL_TEMPLATE_INSTANTIATION (decl) 4298 && DECL_INITIAL (DECL_TEMPLATE_RESULT 4299 (template_for_substitution (decl))))) 4300 { 4301 warning (0, "inline function %q+D used but never defined", decl); 4302 /* Avoid a duplicate warning from check_global_declaration_1. */ 4303 TREE_NO_WARNING (decl) = 1; 4304 } 4305 } 4306 4307 /* So must decls that use a type with no linkage. */ 4308 FOR_EACH_VEC_SAFE_ELT (no_linkage_decls, i, decl) 4309 if (!decl_defined_p (decl)) 4310 no_linkage_error (decl); 4311 4312 /* Then, do the Objective-C stuff. This is where all the 4313 Objective-C module stuff gets generated (symtab, 4314 class/protocol/selector lists etc). This must be done after C++ 4315 templates, destructors etc. so that selectors used in C++ 4316 templates are properly allocated. */ 4317 if (c_dialect_objc ()) 4318 objc_write_global_declarations (); 4319 4320 /* We give C linkage to static constructors and destructors. */ 4321 push_lang_context (lang_name_c); 4322 4323 /* Generate initialization and destruction functions for all 4324 priorities for which they are required. */ 4325 if (priority_info_map) 4326 splay_tree_foreach (priority_info_map, 4327 generate_ctor_and_dtor_functions_for_priority, 4328 /*data=*/&locus); 4329 else if (c_dialect_objc () && objc_static_init_needed_p ()) 4330 /* If this is obj-c++ and we need a static init, call 4331 generate_ctor_or_dtor_function. */ 4332 generate_ctor_or_dtor_function (/*constructor_p=*/true, 4333 DEFAULT_INIT_PRIORITY, &locus); 4334 4335 /* We're done with the splay-tree now. */ 4336 if (priority_info_map) 4337 splay_tree_delete (priority_info_map); 4338 4339 /* Generate any missing aliases. */ 4340 maybe_apply_pending_pragma_weaks (); 4341 4342 /* We're done with static constructors, so we can go back to "C++" 4343 linkage now. */ 4344 pop_lang_context (); 4345 4346 /* Collect candidates for Java hidden aliases. */ 4347 candidates = collect_candidates_for_java_method_aliases (); 4348 4349 timevar_stop (TV_PHASE_DEFERRED); 4350 timevar_start (TV_PHASE_OPT_GEN); 4351 4352 finalize_compilation_unit (); 4353 4354 timevar_stop (TV_PHASE_OPT_GEN); 4355 timevar_start (TV_PHASE_CHECK_DBGINFO); 4356 4357 /* Now, issue warnings about static, but not defined, functions, 4358 etc., and emit debugging information. */ 4359 walk_namespaces (wrapup_globals_for_namespace, /*data=*/&reconsider); 4360 if (vec_safe_length (pending_statics) != 0) 4361 { 4362 check_global_declarations (pending_statics->address (), 4363 pending_statics->length ()); 4364 emit_debug_global_declarations (pending_statics->address (), 4365 pending_statics->length ()); 4366 } 4367 4368 perform_deferred_noexcept_checks (); 4369 4370 /* Generate hidden aliases for Java. */ 4371 if (candidates) 4372 { 4373 build_java_method_aliases (candidates); 4374 pointer_set_destroy (candidates); 4375 } 4376 4377 finish_repo (); 4378 4379 /* The entire file is now complete. If requested, dump everything 4380 to a file. */ 4381 dump_tu (); 4382 4383 if (flag_detailed_statistics) 4384 { 4385 dump_tree_statistics (); 4386 dump_time_statistics (); 4387 } 4388 input_location = locus; 4389 4390 #ifdef ENABLE_CHECKING 4391 validate_conversion_obstack (); 4392 #endif /* ENABLE_CHECKING */ 4393 4394 timevar_stop (TV_PHASE_CHECK_DBGINFO); 4395 } 4396 4397 /* FN is an OFFSET_REF, DOTSTAR_EXPR or MEMBER_REF indicating the 4398 function to call in parse-tree form; it has not yet been 4399 semantically analyzed. ARGS are the arguments to the function. 4400 They have already been semantically analyzed. This may change 4401 ARGS. */ 4402 4403 tree 4404 build_offset_ref_call_from_tree (tree fn, vec<tree, va_gc> **args, 4405 tsubst_flags_t complain) 4406 { 4407 tree orig_fn; 4408 vec<tree, va_gc> *orig_args = NULL; 4409 tree expr; 4410 tree object; 4411 4412 orig_fn = fn; 4413 object = TREE_OPERAND (fn, 0); 4414 4415 if (processing_template_decl) 4416 { 4417 gcc_assert (TREE_CODE (fn) == DOTSTAR_EXPR 4418 || TREE_CODE (fn) == MEMBER_REF); 4419 if (type_dependent_expression_p (fn) 4420 || any_type_dependent_arguments_p (*args)) 4421 return build_nt_call_vec (fn, *args); 4422 4423 orig_args = make_tree_vector_copy (*args); 4424 4425 /* Transform the arguments and add the implicit "this" 4426 parameter. That must be done before the FN is transformed 4427 because we depend on the form of FN. */ 4428 make_args_non_dependent (*args); 4429 object = build_non_dependent_expr (object); 4430 if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE) 4431 { 4432 if (TREE_CODE (fn) == DOTSTAR_EXPR) 4433 object = cp_build_addr_expr (object, complain); 4434 vec_safe_insert (*args, 0, object); 4435 } 4436 /* Now that the arguments are done, transform FN. */ 4437 fn = build_non_dependent_expr (fn); 4438 } 4439 4440 /* A qualified name corresponding to a bound pointer-to-member is 4441 represented as an OFFSET_REF: 4442 4443 struct B { void g(); }; 4444 void (B::*p)(); 4445 void B::g() { (this->*p)(); } */ 4446 if (TREE_CODE (fn) == OFFSET_REF) 4447 { 4448 tree object_addr = cp_build_addr_expr (object, complain); 4449 fn = TREE_OPERAND (fn, 1); 4450 fn = get_member_function_from_ptrfunc (&object_addr, fn, 4451 complain); 4452 vec_safe_insert (*args, 0, object_addr); 4453 } 4454 4455 if (CLASS_TYPE_P (TREE_TYPE (fn))) 4456 expr = build_op_call (fn, args, complain); 4457 else 4458 expr = cp_build_function_call_vec (fn, args, complain); 4459 if (processing_template_decl && expr != error_mark_node) 4460 expr = build_min_non_dep_call_vec (expr, orig_fn, orig_args); 4461 4462 if (orig_args != NULL) 4463 release_tree_vector (orig_args); 4464 4465 return expr; 4466 } 4467 4468 4469 void 4470 check_default_args (tree x) 4471 { 4472 tree arg = TYPE_ARG_TYPES (TREE_TYPE (x)); 4473 bool saw_def = false; 4474 int i = 0 - (TREE_CODE (TREE_TYPE (x)) == METHOD_TYPE); 4475 for (; arg && arg != void_list_node; arg = TREE_CHAIN (arg), ++i) 4476 { 4477 if (TREE_PURPOSE (arg)) 4478 saw_def = true; 4479 else if (saw_def) 4480 { 4481 error ("default argument missing for parameter %P of %q+#D", i, x); 4482 TREE_PURPOSE (arg) = error_mark_node; 4483 } 4484 } 4485 } 4486 4487 /* Return true if function DECL can be inlined. This is used to force 4488 instantiation of methods that might be interesting for inlining. */ 4489 bool 4490 possibly_inlined_p (tree decl) 4491 { 4492 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL); 4493 if (DECL_UNINLINABLE (decl)) 4494 return false; 4495 if (!optimize || pragma_java_exceptions) 4496 return DECL_DECLARED_INLINE_P (decl); 4497 /* When optimizing, we might inline everything when flatten 4498 attribute or heuristics inlining for size or autoinlining 4499 is used. */ 4500 return true; 4501 } 4502 4503 /* Mark DECL (either a _DECL or a BASELINK) as "used" in the program. 4504 If DECL is a specialization or implicitly declared class member, 4505 generate the actual definition. Return false if something goes 4506 wrong, true otherwise. */ 4507 4508 bool 4509 mark_used (tree decl) 4510 { 4511 /* If DECL is a BASELINK for a single function, then treat it just 4512 like the DECL for the function. Otherwise, if the BASELINK is 4513 for an overloaded function, we don't know which function was 4514 actually used until after overload resolution. */ 4515 if (BASELINK_P (decl)) 4516 { 4517 decl = BASELINK_FUNCTIONS (decl); 4518 if (really_overloaded_fn (decl)) 4519 return true; 4520 decl = OVL_CURRENT (decl); 4521 } 4522 4523 /* Set TREE_USED for the benefit of -Wunused. */ 4524 TREE_USED (decl) = 1; 4525 if (DECL_CLONED_FUNCTION_P (decl)) 4526 TREE_USED (DECL_CLONED_FUNCTION (decl)) = 1; 4527 4528 /* Mark enumeration types as used. */ 4529 if (TREE_CODE (decl) == CONST_DECL) 4530 used_types_insert (DECL_CONTEXT (decl)); 4531 4532 if (TREE_CODE (decl) == FUNCTION_DECL 4533 && DECL_DELETED_FN (decl)) 4534 { 4535 if (DECL_ARTIFICIAL (decl)) 4536 { 4537 if (DECL_OVERLOADED_OPERATOR_P (decl) == TYPE_EXPR 4538 && LAMBDA_TYPE_P (DECL_CONTEXT (decl))) 4539 { 4540 /* We mark a lambda conversion op as deleted if we can't 4541 generate it properly; see maybe_add_lambda_conv_op. */ 4542 sorry ("converting lambda which uses %<...%> to " 4543 "function pointer"); 4544 return false; 4545 } 4546 } 4547 error ("use of deleted function %qD", decl); 4548 if (!maybe_explain_implicit_delete (decl)) 4549 error_at (DECL_SOURCE_LOCATION (decl), "declared here"); 4550 return false; 4551 } 4552 4553 /* We can only check DECL_ODR_USED on variables or functions with 4554 DECL_LANG_SPECIFIC set, and these are also the only decls that we 4555 might need special handling for. */ 4556 if ((TREE_CODE (decl) != VAR_DECL && TREE_CODE (decl) != FUNCTION_DECL) 4557 || DECL_LANG_SPECIFIC (decl) == NULL 4558 || DECL_THUNK_P (decl)) 4559 { 4560 if (!processing_template_decl && type_uses_auto (TREE_TYPE (decl))) 4561 { 4562 error ("use of %qD before deduction of %<auto%>", decl); 4563 return false; 4564 } 4565 return true; 4566 } 4567 4568 /* We only want to do this processing once. We don't need to keep trying 4569 to instantiate inline templates, because unit-at-a-time will make sure 4570 we get them compiled before functions that want to inline them. */ 4571 if (DECL_ODR_USED (decl)) 4572 return true; 4573 4574 /* If within finish_function, defer the rest until that function 4575 finishes, otherwise it might recurse. */ 4576 if (defer_mark_used_calls) 4577 { 4578 vec_safe_push (deferred_mark_used_calls, decl); 4579 return true; 4580 } 4581 4582 if (TREE_CODE (decl) == FUNCTION_DECL) 4583 maybe_instantiate_noexcept (decl); 4584 4585 /* Normally, we can wait until instantiation-time to synthesize DECL. 4586 However, if DECL is a static data member initialized with a constant 4587 or a constexpr function, we need it right now because a reference to 4588 such a data member or a call to such function is not value-dependent. 4589 For a function that uses auto in the return type, we need to instantiate 4590 it to find out its type. */ 4591 if ((decl_maybe_constant_var_p (decl) 4592 || (TREE_CODE (decl) == FUNCTION_DECL 4593 && DECL_DECLARED_CONSTEXPR_P (decl)) 4594 || type_uses_auto (TREE_TYPE (decl))) 4595 && DECL_LANG_SPECIFIC (decl) 4596 && DECL_TEMPLATE_INFO (decl) 4597 && !uses_template_parms (DECL_TI_ARGS (decl))) 4598 { 4599 /* Instantiating a function will result in garbage collection. We 4600 must treat this situation as if we were within the body of a 4601 function so as to avoid collecting live data only referenced from 4602 the stack (such as overload resolution candidates). */ 4603 ++function_depth; 4604 instantiate_decl (decl, /*defer_ok=*/false, 4605 /*expl_inst_class_mem_p=*/false); 4606 --function_depth; 4607 } 4608 4609 if (processing_template_decl || in_template_function ()) 4610 return true; 4611 4612 /* Check this too in case we're within fold_non_dependent_expr. */ 4613 if (DECL_TEMPLATE_INFO (decl) 4614 && uses_template_parms (DECL_TI_ARGS (decl))) 4615 return true; 4616 4617 if (type_uses_auto (TREE_TYPE (decl))) 4618 { 4619 error ("use of %qD before deduction of %<auto%>", decl); 4620 return false; 4621 } 4622 4623 /* If we don't need a value, then we don't need to synthesize DECL. */ 4624 if (cp_unevaluated_operand != 0) 4625 return true; 4626 4627 DECL_ODR_USED (decl) = 1; 4628 if (DECL_CLONED_FUNCTION_P (decl)) 4629 DECL_ODR_USED (DECL_CLONED_FUNCTION (decl)) = 1; 4630 4631 /* DR 757: A type without linkage shall not be used as the type of a 4632 variable or function with linkage, unless 4633 o the variable or function has extern "C" linkage (7.5 [dcl.link]), or 4634 o the variable or function is not used (3.2 [basic.def.odr]) or is 4635 defined in the same translation unit. */ 4636 if (cxx_dialect > cxx98 4637 && decl_linkage (decl) != lk_none 4638 && !DECL_EXTERN_C_P (decl) 4639 && !DECL_ARTIFICIAL (decl) 4640 && !decl_defined_p (decl) 4641 && no_linkage_check (TREE_TYPE (decl), /*relaxed_p=*/false)) 4642 { 4643 if (is_local_extern (decl)) 4644 /* There's no way to define a local extern, and adding it to 4645 the vector interferes with GC, so give an error now. */ 4646 no_linkage_error (decl); 4647 else 4648 vec_safe_push (no_linkage_decls, decl); 4649 } 4650 4651 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_DECLARED_INLINE_P (decl) 4652 && !DECL_INITIAL (decl) && !DECL_ARTIFICIAL (decl)) 4653 /* Remember it, so we can check it was defined. */ 4654 note_vague_linkage_fn (decl); 4655 4656 /* Is it a synthesized method that needs to be synthesized? */ 4657 if (TREE_CODE (decl) == FUNCTION_DECL 4658 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl) 4659 && DECL_DEFAULTED_FN (decl) 4660 /* A function defaulted outside the class is synthesized either by 4661 cp_finish_decl or instantiate_decl. */ 4662 && !DECL_DEFAULTED_OUTSIDE_CLASS_P (decl) 4663 && ! DECL_INITIAL (decl)) 4664 { 4665 /* Defer virtual destructors so that thunks get the right 4666 linkage. */ 4667 if (DECL_VIRTUAL_P (decl) && !at_eof) 4668 { 4669 note_vague_linkage_fn (decl); 4670 return true; 4671 } 4672 4673 /* Remember the current location for a function we will end up 4674 synthesizing. Then we can inform the user where it was 4675 required in the case of error. */ 4676 DECL_SOURCE_LOCATION (decl) = input_location; 4677 4678 /* Synthesizing an implicitly defined member function will result in 4679 garbage collection. We must treat this situation as if we were 4680 within the body of a function so as to avoid collecting live data 4681 on the stack (such as overload resolution candidates). 4682 4683 We could just let cp_write_global_declarations handle synthesizing 4684 this function by adding it to deferred_fns, but doing 4685 it at the use site produces better error messages. */ 4686 ++function_depth; 4687 synthesize_method (decl); 4688 --function_depth; 4689 /* If this is a synthesized method we don't need to 4690 do the instantiation test below. */ 4691 } 4692 else if ((TREE_CODE (decl) == FUNCTION_DECL || TREE_CODE (decl) == VAR_DECL) 4693 && DECL_TEMPLATE_INFO (decl) 4694 && (!DECL_EXPLICIT_INSTANTIATION (decl) 4695 || always_instantiate_p (decl))) 4696 /* If this is a function or variable that is an instance of some 4697 template, we now know that we will need to actually do the 4698 instantiation. We check that DECL is not an explicit 4699 instantiation because that is not checked in instantiate_decl. 4700 4701 We put off instantiating functions in order to improve compile 4702 times. Maintaining a stack of active functions is expensive, 4703 and the inliner knows to instantiate any functions it might 4704 need. Therefore, we always try to defer instantiation. */ 4705 { 4706 ++function_depth; 4707 instantiate_decl (decl, /*defer_ok=*/true, 4708 /*expl_inst_class_mem_p=*/false); 4709 --function_depth; 4710 } 4711 4712 return true; 4713 } 4714 4715 #include "gt-cp-decl2.h" 4716