SemaDecl.cpp revision f1af6a70c3060f7eda67da0bfe10f57966fd8073
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "clang/AST/APValue.h" 16#include "clang/AST/ASTConsumer.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/AST/DeclObjC.h" 19#include "clang/AST/ExprCXX.h" 20#include "clang/Parse/DeclSpec.h" 21#include "clang/Basic/Diagnostic.h" 22#include "clang/Basic/TargetInfo.h" 23#include "clang/Basic/SourceManager.h" 24// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 25#include "clang/Lex/Preprocessor.h" 26#include "clang/Lex/HeaderSearch.h" 27#include "llvm/ADT/SmallSet.h" 28#include "llvm/ADT/StringExtras.h" 29using namespace clang; 30 31Sema::TypeTy *Sema::isTypeName(const IdentifierInfo &II, Scope *S) { 32 Decl *IIDecl = LookupDecl(&II, Decl::IDNS_Ordinary, S, false); 33 34 if (IIDecl && (isa<TypedefDecl>(IIDecl) || 35 isa<ObjCInterfaceDecl>(IIDecl) || 36 isa<TagDecl>(IIDecl))) 37 return IIDecl; 38 return 0; 39} 40 41DeclContext *Sema::getDCParent(DeclContext *DC) { 42 // If CurContext is a ObjC method, getParent() will return NULL. 43 if (isa<ObjCMethodDecl>(DC)) 44 return Context.getTranslationUnitDecl(); 45 46 // A C++ inline method is parsed *after* the topmost class it was declared in 47 // is fully parsed (it's "complete"). 48 // The parsing of a C++ inline method happens at the declaration context of 49 // the topmost (non-nested) class it is declared in. 50 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 51 assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record."); 52 DC = MD->getParent(); 53 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getParent())) 54 DC = RD; 55 56 // Return the declaration context of the topmost class the inline method is 57 // declared in. 58 return DC; 59 } 60 61 return DC->getParent(); 62} 63 64void Sema::PushDeclContext(DeclContext *DC) { 65 assert(getDCParent(DC) == CurContext && 66 "The next DeclContext should be directly contained in the current one."); 67 CurContext = DC; 68} 69 70void Sema::PopDeclContext() { 71 assert(CurContext && "DeclContext imbalance!"); 72 CurContext = getDCParent(CurContext); 73} 74 75/// Add this decl to the scope shadowed decl chains. 76void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 77 S->AddDecl(D); 78 79 // C++ [basic.scope]p4: 80 // -- exactly one declaration shall declare a class name or 81 // enumeration name that is not a typedef name and the other 82 // declarations shall all refer to the same object or 83 // enumerator, or all refer to functions and function templates; 84 // in this case the class name or enumeration name is hidden. 85 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 86 // We are pushing the name of a tag (enum or class). 87 IdentifierResolver::iterator 88 I = IdResolver.begin(TD->getIdentifier(), 89 TD->getDeclContext(), false/*LookInParentCtx*/); 90 if (I != IdResolver.end() && isDeclInScope(*I, TD->getDeclContext(), S)) { 91 // There is already a declaration with the same name in the same 92 // scope. It must be found before we find the new declaration, 93 // so swap the order on the shadowed declaration chain. 94 95 IdResolver.AddShadowedDecl(TD, *I); 96 return; 97 } 98 } else if (getLangOptions().CPlusPlus && isa<FunctionDecl>(D)) { 99 FunctionDecl *FD = cast<FunctionDecl>(D); 100 // We are pushing the name of a function, which might be an 101 // overloaded name. 102 IdentifierResolver::iterator 103 I = IdResolver.begin(FD->getIdentifier(), 104 FD->getDeclContext(), false/*LookInParentCtx*/); 105 if (I != IdResolver.end() && 106 IdResolver.isDeclInScope(*I, FD->getDeclContext(), S) && 107 (isa<OverloadedFunctionDecl>(*I) || isa<FunctionDecl>(*I))) { 108 // There is already a declaration with the same name in the same 109 // scope. It must be a function or an overloaded function. 110 OverloadedFunctionDecl* Ovl = dyn_cast<OverloadedFunctionDecl>(*I); 111 if (!Ovl) { 112 // We haven't yet overloaded this function. Take the existing 113 // FunctionDecl and put it into an OverloadedFunctionDecl. 114 Ovl = OverloadedFunctionDecl::Create(Context, 115 FD->getDeclContext(), 116 FD->getIdentifier()); 117 Ovl->addOverload(dyn_cast<FunctionDecl>(*I)); 118 119 // Remove the name binding to the existing FunctionDecl... 120 IdResolver.RemoveDecl(*I); 121 122 // ... and put the OverloadedFunctionDecl in its place. 123 IdResolver.AddDecl(Ovl); 124 } 125 126 // We have an OverloadedFunctionDecl. Add the new FunctionDecl 127 // to its list of overloads. 128 Ovl->addOverload(FD); 129 130 return; 131 } 132 } 133 134 IdResolver.AddDecl(D); 135} 136 137void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 138 if (S->decl_empty()) return; 139 assert((S->getFlags() & Scope::DeclScope) &&"Scope shouldn't contain decls!"); 140 141 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 142 I != E; ++I) { 143 Decl *TmpD = static_cast<Decl*>(*I); 144 assert(TmpD && "This decl didn't get pushed??"); 145 146 if (isa<CXXFieldDecl>(TmpD)) continue; 147 148 assert(isa<ScopedDecl>(TmpD) && "Decl isn't ScopedDecl?"); 149 ScopedDecl *D = cast<ScopedDecl>(TmpD); 150 151 IdentifierInfo *II = D->getIdentifier(); 152 if (!II) continue; 153 154 // We only want to remove the decls from the identifier decl chains for 155 // local scopes, when inside a function/method. 156 if (S->getFnParent() != 0) 157 IdResolver.RemoveDecl(D); 158 159 // Chain this decl to the containing DeclContext. 160 D->setNext(CurContext->getDeclChain()); 161 CurContext->setDeclChain(D); 162 } 163} 164 165/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 166/// return 0 if one not found. 167ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 168 // The third "scope" argument is 0 since we aren't enabling lazy built-in 169 // creation from this context. 170 Decl *IDecl = LookupDecl(Id, Decl::IDNS_Ordinary, 0, false); 171 172 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 173} 174 175/// LookupDecl - Look up the inner-most declaration in the specified 176/// namespace. 177Decl *Sema::LookupDecl(const IdentifierInfo *II, unsigned NSI, 178 Scope *S, bool enableLazyBuiltinCreation) { 179 if (II == 0) return 0; 180 unsigned NS = NSI; 181 if (getLangOptions().CPlusPlus && (NS & Decl::IDNS_Ordinary)) 182 NS |= Decl::IDNS_Tag; 183 184 // Scan up the scope chain looking for a decl that matches this identifier 185 // that is in the appropriate namespace. This search should not take long, as 186 // shadowing of names is uncommon, and deep shadowing is extremely uncommon. 187 for (IdentifierResolver::iterator 188 I = IdResolver.begin(II, CurContext), E = IdResolver.end(); I != E; ++I) 189 if ((*I)->getIdentifierNamespace() & NS) 190 return *I; 191 192 // If we didn't find a use of this identifier, and if the identifier 193 // corresponds to a compiler builtin, create the decl object for the builtin 194 // now, injecting it into translation unit scope, and return it. 195 if (NS & Decl::IDNS_Ordinary) { 196 if (enableLazyBuiltinCreation) { 197 // If this is a builtin on this (or all) targets, create the decl. 198 if (unsigned BuiltinID = II->getBuiltinID()) 199 return LazilyCreateBuiltin((IdentifierInfo *)II, BuiltinID, S); 200 } 201 if (getLangOptions().ObjC1) { 202 // @interface and @compatibility_alias introduce typedef-like names. 203 // Unlike typedef's, they can only be introduced at file-scope (and are 204 // therefore not scoped decls). They can, however, be shadowed by 205 // other names in IDNS_Ordinary. 206 ObjCInterfaceDeclsTy::iterator IDI = ObjCInterfaceDecls.find(II); 207 if (IDI != ObjCInterfaceDecls.end()) 208 return IDI->second; 209 ObjCAliasTy::iterator I = ObjCAliasDecls.find(II); 210 if (I != ObjCAliasDecls.end()) 211 return I->second->getClassInterface(); 212 } 213 } 214 return 0; 215} 216 217void Sema::InitBuiltinVaListType() { 218 if (!Context.getBuiltinVaListType().isNull()) 219 return; 220 221 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 222 Decl *VaDecl = LookupDecl(VaIdent, Decl::IDNS_Ordinary, TUScope); 223 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 224 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 225} 226 227/// LazilyCreateBuiltin - The specified Builtin-ID was first used at file scope. 228/// lazily create a decl for it. 229ScopedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 230 Scope *S) { 231 Builtin::ID BID = (Builtin::ID)bid; 232 233 if (Context.BuiltinInfo.hasVAListUse(BID)) 234 InitBuiltinVaListType(); 235 236 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context); 237 FunctionDecl *New = FunctionDecl::Create(Context, 238 Context.getTranslationUnitDecl(), 239 SourceLocation(), II, R, 240 FunctionDecl::Extern, false, 0); 241 242 // Create Decl objects for each parameter, adding them to the 243 // FunctionDecl. 244 if (FunctionTypeProto *FT = dyn_cast<FunctionTypeProto>(R)) { 245 llvm::SmallVector<ParmVarDecl*, 16> Params; 246 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 247 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 248 FT->getArgType(i), VarDecl::None, 0, 249 0)); 250 New->setParams(&Params[0], Params.size()); 251 } 252 253 254 255 // TUScope is the translation-unit scope to insert this function into. 256 PushOnScopeChains(New, TUScope); 257 return New; 258} 259 260/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the same name 261/// and scope as a previous declaration 'Old'. Figure out how to resolve this 262/// situation, merging decls or emitting diagnostics as appropriate. 263/// 264TypedefDecl *Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 265 // Allow multiple definitions for ObjC built-in typedefs. 266 // FIXME: Verify the underlying types are equivalent! 267 if (getLangOptions().ObjC1) { 268 const IdentifierInfo *typeIdent = New->getIdentifier(); 269 if (typeIdent == Ident_id) { 270 Context.setObjCIdType(New); 271 return New; 272 } else if (typeIdent == Ident_Class) { 273 Context.setObjCClassType(New); 274 return New; 275 } else if (typeIdent == Ident_SEL) { 276 Context.setObjCSelType(New); 277 return New; 278 } else if (typeIdent == Ident_Protocol) { 279 Context.setObjCProtoType(New->getUnderlyingType()); 280 return New; 281 } 282 // Fall through - the typedef name was not a builtin type. 283 } 284 // Verify the old decl was also a typedef. 285 TypedefDecl *Old = dyn_cast<TypedefDecl>(OldD); 286 if (!Old) { 287 Diag(New->getLocation(), diag::err_redefinition_different_kind, 288 New->getName()); 289 Diag(OldD->getLocation(), diag::err_previous_definition); 290 return New; 291 } 292 293 // If the typedef types are not identical, reject them in all languages and 294 // with any extensions enabled. 295 if (Old->getUnderlyingType() != New->getUnderlyingType() && 296 Context.getCanonicalType(Old->getUnderlyingType()) != 297 Context.getCanonicalType(New->getUnderlyingType())) { 298 Diag(New->getLocation(), diag::err_redefinition_different_typedef, 299 New->getUnderlyingType().getAsString(), 300 Old->getUnderlyingType().getAsString()); 301 Diag(Old->getLocation(), diag::err_previous_definition); 302 return Old; 303 } 304 305 if (getLangOptions().Microsoft) return New; 306 307 // Redeclaration of a type is a constraint violation (6.7.2.3p1). 308 // Apparently GCC, Intel, and Sun all silently ignore the redeclaration if 309 // *either* declaration is in a system header. The code below implements 310 // this adhoc compatibility rule. FIXME: The following code will not 311 // work properly when compiling ".i" files (containing preprocessed output). 312 if (PP.getDiagnostics().getSuppressSystemWarnings()) { 313 SourceManager &SrcMgr = Context.getSourceManager(); 314 if (SrcMgr.isInSystemHeader(Old->getLocation())) 315 return New; 316 if (SrcMgr.isInSystemHeader(New->getLocation())) 317 return New; 318 } 319 320 Diag(New->getLocation(), diag::err_redefinition, New->getName()); 321 Diag(Old->getLocation(), diag::err_previous_definition); 322 return New; 323} 324 325/// DeclhasAttr - returns true if decl Declaration already has the target 326/// attribute. 327static bool DeclHasAttr(const Decl *decl, const Attr *target) { 328 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 329 if (attr->getKind() == target->getKind()) 330 return true; 331 332 return false; 333} 334 335/// MergeAttributes - append attributes from the Old decl to the New one. 336static void MergeAttributes(Decl *New, Decl *Old) { 337 Attr *attr = const_cast<Attr*>(Old->getAttrs()), *tmp; 338 339 while (attr) { 340 tmp = attr; 341 attr = attr->getNext(); 342 343 if (!DeclHasAttr(New, tmp)) { 344 New->addAttr(tmp); 345 } else { 346 tmp->setNext(0); 347 delete(tmp); 348 } 349 } 350 351 Old->invalidateAttrs(); 352} 353 354/// MergeFunctionDecl - We just parsed a function 'New' from 355/// declarator D which has the same name and scope as a previous 356/// declaration 'Old'. Figure out how to resolve this situation, 357/// merging decls or emitting diagnostics as appropriate. 358/// Redeclaration will be set true if this New is a redeclaration OldD. 359/// 360/// In C++, New and Old must be declarations that are not 361/// overloaded. Use IsOverload to determine whether New and Old are 362/// overloaded, and to select the Old declaration that New should be 363/// merged with. 364FunctionDecl * 365Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD, bool &Redeclaration) { 366 assert(!isa<OverloadedFunctionDecl>(OldD) && 367 "Cannot merge with an overloaded function declaration"); 368 369 Redeclaration = false; 370 // Verify the old decl was also a function. 371 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 372 if (!Old) { 373 Diag(New->getLocation(), diag::err_redefinition_different_kind, 374 New->getName()); 375 Diag(OldD->getLocation(), diag::err_previous_definition); 376 return New; 377 } 378 379 // Determine whether the previous declaration was a definition, 380 // implicit declaration, or a declaration. 381 diag::kind PrevDiag; 382 if (Old->isThisDeclarationADefinition()) 383 PrevDiag = diag::err_previous_definition; 384 else if (Old->isImplicit()) 385 PrevDiag = diag::err_previous_implicit_declaration; 386 else 387 PrevDiag = diag::err_previous_declaration; 388 389 QualType OldQType = Context.getCanonicalType(Old->getType()); 390 QualType NewQType = Context.getCanonicalType(New->getType()); 391 392 if (getLangOptions().CPlusPlus) { 393 // (C++98 13.1p2): 394 // Certain function declarations cannot be overloaded: 395 // -- Function declarations that differ only in the return type 396 // cannot be overloaded. 397 QualType OldReturnType 398 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 399 QualType NewReturnType 400 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 401 if (OldReturnType != NewReturnType) { 402 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 403 Diag(Old->getLocation(), PrevDiag); 404 return New; 405 } 406 407 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 408 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 409 if (OldMethod && NewMethod) { 410 // -- Member function declarations with the same name and the 411 // same parameter types cannot be overloaded if any of them 412 // is a static member function declaration. 413 if (OldMethod->isStatic() || NewMethod->isStatic()) { 414 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 415 Diag(Old->getLocation(), PrevDiag); 416 return New; 417 } 418 } 419 420 // (C++98 8.3.5p3): 421 // All declarations for a function shall agree exactly in both the 422 // return type and the parameter-type-list. 423 if (OldQType == NewQType) { 424 // We have a redeclaration. 425 MergeAttributes(New, Old); 426 Redeclaration = true; 427 return MergeCXXFunctionDecl(New, Old); 428 } 429 430 // Fall through for conflicting redeclarations and redefinitions. 431 } 432 433 // C: Function types need to be compatible, not identical. This handles 434 // duplicate function decls like "void f(int); void f(enum X);" properly. 435 if (!getLangOptions().CPlusPlus && 436 Context.typesAreCompatible(OldQType, NewQType)) { 437 MergeAttributes(New, Old); 438 Redeclaration = true; 439 return New; 440 } 441 442 // A function that has already been declared has been redeclared or defined 443 // with a different type- show appropriate diagnostic 444 445 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 446 // TODO: This is totally simplistic. It should handle merging functions 447 // together etc, merging extern int X; int X; ... 448 Diag(New->getLocation(), diag::err_conflicting_types, New->getName()); 449 Diag(Old->getLocation(), PrevDiag); 450 return New; 451} 452 453/// Predicate for C "tentative" external object definitions (C99 6.9.2). 454static bool isTentativeDefinition(VarDecl *VD) { 455 if (VD->isFileVarDecl()) 456 return (!VD->getInit() && 457 (VD->getStorageClass() == VarDecl::None || 458 VD->getStorageClass() == VarDecl::Static)); 459 return false; 460} 461 462/// CheckForFileScopedRedefinitions - Make sure we forgo redefinition errors 463/// when dealing with C "tentative" external object definitions (C99 6.9.2). 464void Sema::CheckForFileScopedRedefinitions(Scope *S, VarDecl *VD) { 465 bool VDIsTentative = isTentativeDefinition(VD); 466 bool VDIsIncompleteArray = VD->getType()->isIncompleteArrayType(); 467 468 for (IdentifierResolver::iterator 469 I = IdResolver.begin(VD->getIdentifier(), 470 VD->getDeclContext(), false/*LookInParentCtx*/), 471 E = IdResolver.end(); I != E; ++I) { 472 if (*I != VD && isDeclInScope(*I, VD->getDeclContext(), S)) { 473 VarDecl *OldDecl = dyn_cast<VarDecl>(*I); 474 475 // Handle the following case: 476 // int a[10]; 477 // int a[]; - the code below makes sure we set the correct type. 478 // int a[11]; - this is an error, size isn't 10. 479 if (OldDecl && VDIsTentative && VDIsIncompleteArray && 480 OldDecl->getType()->isConstantArrayType()) 481 VD->setType(OldDecl->getType()); 482 483 // Check for "tentative" definitions. We can't accomplish this in 484 // MergeVarDecl since the initializer hasn't been attached. 485 if (!OldDecl || isTentativeDefinition(OldDecl) || VDIsTentative) 486 continue; 487 488 // Handle __private_extern__ just like extern. 489 if (OldDecl->getStorageClass() != VarDecl::Extern && 490 OldDecl->getStorageClass() != VarDecl::PrivateExtern && 491 VD->getStorageClass() != VarDecl::Extern && 492 VD->getStorageClass() != VarDecl::PrivateExtern) { 493 Diag(VD->getLocation(), diag::err_redefinition, VD->getName()); 494 Diag(OldDecl->getLocation(), diag::err_previous_definition); 495 } 496 } 497 } 498} 499 500/// MergeVarDecl - We just parsed a variable 'New' which has the same name 501/// and scope as a previous declaration 'Old'. Figure out how to resolve this 502/// situation, merging decls or emitting diagnostics as appropriate. 503/// 504/// Tentative definition rules (C99 6.9.2p2) are checked by 505/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 506/// definitions here, since the initializer hasn't been attached. 507/// 508VarDecl *Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 509 // Verify the old decl was also a variable. 510 VarDecl *Old = dyn_cast<VarDecl>(OldD); 511 if (!Old) { 512 Diag(New->getLocation(), diag::err_redefinition_different_kind, 513 New->getName()); 514 Diag(OldD->getLocation(), diag::err_previous_definition); 515 return New; 516 } 517 518 MergeAttributes(New, Old); 519 520 // Verify the types match. 521 QualType OldCType = Context.getCanonicalType(Old->getType()); 522 QualType NewCType = Context.getCanonicalType(New->getType()); 523 if (OldCType != NewCType && !Context.typesAreCompatible(OldCType, NewCType)) { 524 Diag(New->getLocation(), diag::err_redefinition, New->getName()); 525 Diag(Old->getLocation(), diag::err_previous_definition); 526 return New; 527 } 528 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 529 if (New->getStorageClass() == VarDecl::Static && 530 (Old->getStorageClass() == VarDecl::None || 531 Old->getStorageClass() == VarDecl::Extern)) { 532 Diag(New->getLocation(), diag::err_static_non_static, New->getName()); 533 Diag(Old->getLocation(), diag::err_previous_definition); 534 return New; 535 } 536 // C99 6.2.2p4: Check if we have a non-static decl followed by a static. 537 if (New->getStorageClass() != VarDecl::Static && 538 Old->getStorageClass() == VarDecl::Static) { 539 Diag(New->getLocation(), diag::err_non_static_static, New->getName()); 540 Diag(Old->getLocation(), diag::err_previous_definition); 541 return New; 542 } 543 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 544 if (New->getStorageClass() != VarDecl::Extern && !New->isFileVarDecl()) { 545 Diag(New->getLocation(), diag::err_redefinition, New->getName()); 546 Diag(Old->getLocation(), diag::err_previous_definition); 547 } 548 return New; 549} 550 551/// CheckParmsForFunctionDef - Check that the parameters of the given 552/// function are appropriate for the definition of a function. This 553/// takes care of any checks that cannot be performed on the 554/// declaration itself, e.g., that the types of each of the function 555/// parameters are complete. 556bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 557 bool HasInvalidParm = false; 558 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 559 ParmVarDecl *Param = FD->getParamDecl(p); 560 561 // C99 6.7.5.3p4: the parameters in a parameter type list in a 562 // function declarator that is part of a function definition of 563 // that function shall not have incomplete type. 564 if (Param->getType()->isIncompleteType() && 565 !Param->isInvalidDecl()) { 566 Diag(Param->getLocation(), diag::err_typecheck_decl_incomplete_type, 567 Param->getType().getAsString()); 568 Param->setInvalidDecl(); 569 HasInvalidParm = true; 570 } 571 } 572 573 return HasInvalidParm; 574} 575 576/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 577/// no declarator (e.g. "struct foo;") is parsed. 578Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 579 // TODO: emit error on 'int;' or 'const enum foo;'. 580 // TODO: emit error on 'typedef int;' 581 // if (!DS.isMissingDeclaratorOk()) Diag(...); 582 583 return dyn_cast_or_null<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 584} 585 586bool Sema::CheckSingleInitializer(Expr *&Init, QualType DeclType) { 587 // Get the type before calling CheckSingleAssignmentConstraints(), since 588 // it can promote the expression. 589 QualType InitType = Init->getType(); 590 591 AssignConvertType ConvTy = CheckSingleAssignmentConstraints(DeclType, Init); 592 return DiagnoseAssignmentResult(ConvTy, Init->getLocStart(), DeclType, 593 InitType, Init, "initializing"); 594} 595 596bool Sema::CheckStringLiteralInit(StringLiteral *strLiteral, QualType &DeclT) { 597 const ArrayType *AT = Context.getAsArrayType(DeclT); 598 599 if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) { 600 // C99 6.7.8p14. We have an array of character type with unknown size 601 // being initialized to a string literal. 602 llvm::APSInt ConstVal(32); 603 ConstVal = strLiteral->getByteLength() + 1; 604 // Return a new array type (C99 6.7.8p22). 605 DeclT = Context.getConstantArrayType(IAT->getElementType(), ConstVal, 606 ArrayType::Normal, 0); 607 } else { 608 const ConstantArrayType *CAT = cast<ConstantArrayType>(AT); 609 // C99 6.7.8p14. We have an array of character type with known size. 610 // FIXME: Avoid truncation for 64-bit length strings. 611 if (strLiteral->getByteLength() > (unsigned)CAT->getSize().getZExtValue()) 612 Diag(strLiteral->getSourceRange().getBegin(), 613 diag::warn_initializer_string_for_char_array_too_long, 614 strLiteral->getSourceRange()); 615 } 616 // Set type from "char *" to "constant array of char". 617 strLiteral->setType(DeclT); 618 // For now, we always return false (meaning success). 619 return false; 620} 621 622StringLiteral *Sema::IsStringLiteralInit(Expr *Init, QualType DeclType) { 623 const ArrayType *AT = Context.getAsArrayType(DeclType); 624 if (AT && AT->getElementType()->isCharType()) { 625 return dyn_cast<StringLiteral>(Init); 626 } 627 return 0; 628} 629 630bool Sema::CheckInitializerTypes(Expr *&Init, QualType &DeclType) { 631 // C99 6.7.8p3: The type of the entity to be initialized shall be an array 632 // of unknown size ("[]") or an object type that is not a variable array type. 633 if (const VariableArrayType *VAT = Context.getAsVariableArrayType(DeclType)) 634 return Diag(VAT->getSizeExpr()->getLocStart(), 635 diag::err_variable_object_no_init, 636 VAT->getSizeExpr()->getSourceRange()); 637 638 InitListExpr *InitList = dyn_cast<InitListExpr>(Init); 639 if (!InitList) { 640 // FIXME: Handle wide strings 641 if (StringLiteral *strLiteral = IsStringLiteralInit(Init, DeclType)) 642 return CheckStringLiteralInit(strLiteral, DeclType); 643 644 // C99 6.7.8p16. 645 if (DeclType->isArrayType()) 646 return Diag(Init->getLocStart(), 647 diag::err_array_init_list_required, 648 Init->getSourceRange()); 649 650 return CheckSingleInitializer(Init, DeclType); 651 } 652 653 InitListChecker CheckInitList(this, InitList, DeclType); 654 return CheckInitList.HadError(); 655} 656 657Sema::DeclTy * 658Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl) { 659 ScopedDecl *LastDeclarator = dyn_cast_or_null<ScopedDecl>((Decl *)lastDecl); 660 IdentifierInfo *II = D.getIdentifier(); 661 662 // All of these full declarators require an identifier. If it doesn't have 663 // one, the ParsedFreeStandingDeclSpec action should be used. 664 if (II == 0) { 665 Diag(D.getDeclSpec().getSourceRange().getBegin(), 666 diag::err_declarator_need_ident, 667 D.getDeclSpec().getSourceRange(), D.getSourceRange()); 668 return 0; 669 } 670 671 // The scope passed in may not be a decl scope. Zip up the scope tree until 672 // we find one that is. 673 while ((S->getFlags() & Scope::DeclScope) == 0) 674 S = S->getParent(); 675 676 // See if this is a redefinition of a variable in the same scope. 677 Decl *PrevDecl = LookupDecl(II, Decl::IDNS_Ordinary, S); 678 ScopedDecl *New; 679 bool InvalidDecl = false; 680 681 // In C++, the previous declaration we find might be a tag type 682 // (class or enum). In this case, the new declaration will hide the 683 // tag type. 684 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag) 685 PrevDecl = 0; 686 687 QualType R = GetTypeForDeclarator(D, S); 688 assert(!R.isNull() && "GetTypeForDeclarator() returned null type"); 689 690 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 691 // Check that there are no default arguments (C++ only). 692 if (getLangOptions().CPlusPlus) 693 CheckExtraCXXDefaultArguments(D); 694 695 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 696 if (!NewTD) return 0; 697 698 // Handle attributes prior to checking for duplicates in MergeVarDecl 699 ProcessDeclAttributes(NewTD, D); 700 // Merge the decl with the existing one if appropriate. If the decl is 701 // in an outer scope, it isn't the same thing. 702 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S)) { 703 NewTD = MergeTypeDefDecl(NewTD, PrevDecl); 704 if (NewTD == 0) return 0; 705 } 706 New = NewTD; 707 if (S->getFnParent() == 0) { 708 // C99 6.7.7p2: If a typedef name specifies a variably modified type 709 // then it shall have block scope. 710 if (NewTD->getUnderlyingType()->isVariablyModifiedType()) { 711 // FIXME: Diagnostic needs to be fixed. 712 Diag(D.getIdentifierLoc(), diag::err_typecheck_illegal_vla); 713 InvalidDecl = true; 714 } 715 } 716 } else if (R.getTypePtr()->isFunctionType()) { 717 FunctionDecl::StorageClass SC = FunctionDecl::None; 718 switch (D.getDeclSpec().getStorageClassSpec()) { 719 default: assert(0 && "Unknown storage class!"); 720 case DeclSpec::SCS_auto: 721 case DeclSpec::SCS_register: 722 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_func, 723 R.getAsString()); 724 InvalidDecl = true; 725 break; 726 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 727 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 728 case DeclSpec::SCS_static: SC = FunctionDecl::Static; break; 729 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 730 } 731 732 bool isInline = D.getDeclSpec().isInlineSpecified(); 733 FunctionDecl *NewFD; 734 if (D.getContext() == Declarator::MemberContext) { 735 // This is a C++ method declaration. 736 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(CurContext), 737 D.getIdentifierLoc(), II, R, 738 (SC == FunctionDecl::Static), isInline, 739 LastDeclarator); 740 } else { 741 NewFD = FunctionDecl::Create(Context, CurContext, 742 D.getIdentifierLoc(), 743 II, R, SC, isInline, LastDeclarator, 744 // FIXME: Move to DeclGroup... 745 D.getDeclSpec().getSourceRange().getBegin()); 746 } 747 // Handle attributes. 748 ProcessDeclAttributes(NewFD, D); 749 750 // Handle GNU asm-label extension (encoded as an attribute). 751 if (Expr *E = (Expr*) D.getAsmLabel()) { 752 // The parser guarantees this is a string. 753 StringLiteral *SE = cast<StringLiteral>(E); 754 NewFD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 755 SE->getByteLength()))); 756 } 757 758 // Copy the parameter declarations from the declarator D to 759 // the function declaration NewFD, if they are available. 760 if (D.getNumTypeObjects() > 0) { 761 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 762 763 // Create Decl objects for each parameter, adding them to the 764 // FunctionDecl. 765 llvm::SmallVector<ParmVarDecl*, 16> Params; 766 767 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 768 // function that takes no arguments, not a function that takes a 769 // single void argument. 770 // We let through "const void" here because Sema::GetTypeForDeclarator 771 // already checks for that case. 772 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 773 FTI.ArgInfo[0].Param && 774 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 775 // empty arg list, don't push any params. 776 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 777 778 // In C++, the empty parameter-type-list must be spelled "void"; a 779 // typedef of void is not permitted. 780 if (getLangOptions().CPlusPlus && 781 Param->getType().getUnqualifiedType() != Context.VoidTy) { 782 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 783 } 784 785 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 786 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 787 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 788 } 789 790 NewFD->setParams(&Params[0], Params.size()); 791 } 792 793 // Merge the decl with the existing one if appropriate. Since C functions 794 // are in a flat namespace, make sure we consider decls in outer scopes. 795 if (PrevDecl && 796 (!getLangOptions().CPlusPlus||isDeclInScope(PrevDecl, CurContext, S))) { 797 bool Redeclaration = false; 798 799 // If C++, determine whether NewFD is an overload of PrevDecl or 800 // a declaration that requires merging. If it's an overload, 801 // there's no more work to do here; we'll just add the new 802 // function to the scope. 803 OverloadedFunctionDecl::function_iterator MatchedDecl; 804 if (!getLangOptions().CPlusPlus || 805 !IsOverload(NewFD, PrevDecl, MatchedDecl)) { 806 Decl *OldDecl = PrevDecl; 807 808 // If PrevDecl was an overloaded function, extract the 809 // FunctionDecl that matched. 810 if (isa<OverloadedFunctionDecl>(PrevDecl)) 811 OldDecl = *MatchedDecl; 812 813 // NewFD and PrevDecl represent declarations that need to be 814 // merged. 815 NewFD = MergeFunctionDecl(NewFD, OldDecl, Redeclaration); 816 817 if (NewFD == 0) return 0; 818 if (Redeclaration) { 819 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 820 821 if (OldDecl == PrevDecl) { 822 // Remove the name binding for the previous 823 // declaration. We'll add the binding back later, but then 824 // it will refer to the new declaration (which will 825 // contain more information). 826 IdResolver.RemoveDecl(cast<NamedDecl>(PrevDecl)); 827 } else { 828 // We need to update the OverloadedFunctionDecl with the 829 // latest declaration of this function, so that name 830 // lookup will always refer to the latest declaration of 831 // this function. 832 *MatchedDecl = NewFD; 833 834 // Add the redeclaration to the current scope, since we'll 835 // be skipping PushOnScopeChains. 836 S->AddDecl(NewFD); 837 838 return NewFD; 839 } 840 } 841 } 842 } 843 New = NewFD; 844 845 // In C++, check default arguments now that we have merged decls. 846 if (getLangOptions().CPlusPlus) 847 CheckCXXDefaultArguments(NewFD); 848 } else { 849 // Check that there are no default arguments (C++ only). 850 if (getLangOptions().CPlusPlus) 851 CheckExtraCXXDefaultArguments(D); 852 853 if (R.getTypePtr()->isObjCInterfaceType()) { 854 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object, 855 D.getIdentifier()->getName()); 856 InvalidDecl = true; 857 } 858 859 VarDecl *NewVD; 860 VarDecl::StorageClass SC; 861 switch (D.getDeclSpec().getStorageClassSpec()) { 862 default: assert(0 && "Unknown storage class!"); 863 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 864 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 865 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 866 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 867 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 868 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 869 } 870 if (D.getContext() == Declarator::MemberContext) { 871 assert(SC == VarDecl::Static && "Invalid storage class for member!"); 872 // This is a static data member for a C++ class. 873 NewVD = CXXClassVarDecl::Create(Context, cast<CXXRecordDecl>(CurContext), 874 D.getIdentifierLoc(), II, 875 R, LastDeclarator); 876 } else { 877 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 878 if (S->getFnParent() == 0) { 879 // C99 6.9p2: The storage-class specifiers auto and register shall not 880 // appear in the declaration specifiers in an external declaration. 881 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 882 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope, 883 R.getAsString()); 884 InvalidDecl = true; 885 } 886 } 887 NewVD = VarDecl::Create(Context, CurContext, D.getIdentifierLoc(), 888 II, R, SC, LastDeclarator, 889 // FIXME: Move to DeclGroup... 890 D.getDeclSpec().getSourceRange().getBegin()); 891 NewVD->setThreadSpecified(ThreadSpecified); 892 } 893 // Handle attributes prior to checking for duplicates in MergeVarDecl 894 ProcessDeclAttributes(NewVD, D); 895 896 // Handle GNU asm-label extension (encoded as an attribute). 897 if (Expr *E = (Expr*) D.getAsmLabel()) { 898 // The parser guarantees this is a string. 899 StringLiteral *SE = cast<StringLiteral>(E); 900 NewVD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 901 SE->getByteLength()))); 902 } 903 904 // Emit an error if an address space was applied to decl with local storage. 905 // This includes arrays of objects with address space qualifiers, but not 906 // automatic variables that point to other address spaces. 907 // ISO/IEC TR 18037 S5.1.2 908 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 909 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 910 InvalidDecl = true; 911 } 912 // Merge the decl with the existing one if appropriate. If the decl is 913 // in an outer scope, it isn't the same thing. 914 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S)) { 915 NewVD = MergeVarDecl(NewVD, PrevDecl); 916 if (NewVD == 0) return 0; 917 } 918 New = NewVD; 919 } 920 921 // If this has an identifier, add it to the scope stack. 922 if (II) 923 PushOnScopeChains(New, S); 924 // If any semantic error occurred, mark the decl as invalid. 925 if (D.getInvalidType() || InvalidDecl) 926 New->setInvalidDecl(); 927 928 return New; 929} 930 931bool Sema::CheckAddressConstantExpressionLValue(const Expr* Init) { 932 switch (Init->getStmtClass()) { 933 default: 934 Diag(Init->getExprLoc(), 935 diag::err_init_element_not_constant, Init->getSourceRange()); 936 return true; 937 case Expr::ParenExprClass: { 938 const ParenExpr* PE = cast<ParenExpr>(Init); 939 return CheckAddressConstantExpressionLValue(PE->getSubExpr()); 940 } 941 case Expr::CompoundLiteralExprClass: 942 return cast<CompoundLiteralExpr>(Init)->isFileScope(); 943 case Expr::DeclRefExprClass: { 944 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 945 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 946 if (VD->hasGlobalStorage()) 947 return false; 948 Diag(Init->getExprLoc(), 949 diag::err_init_element_not_constant, Init->getSourceRange()); 950 return true; 951 } 952 if (isa<FunctionDecl>(D)) 953 return false; 954 Diag(Init->getExprLoc(), 955 diag::err_init_element_not_constant, Init->getSourceRange()); 956 return true; 957 } 958 case Expr::MemberExprClass: { 959 const MemberExpr *M = cast<MemberExpr>(Init); 960 if (M->isArrow()) 961 return CheckAddressConstantExpression(M->getBase()); 962 return CheckAddressConstantExpressionLValue(M->getBase()); 963 } 964 case Expr::ArraySubscriptExprClass: { 965 // FIXME: Should we pedwarn for "x[0+0]" (where x is a pointer)? 966 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(Init); 967 return CheckAddressConstantExpression(ASE->getBase()) || 968 CheckArithmeticConstantExpression(ASE->getIdx()); 969 } 970 case Expr::StringLiteralClass: 971 case Expr::PredefinedExprClass: 972 return false; 973 case Expr::UnaryOperatorClass: { 974 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 975 976 // C99 6.6p9 977 if (Exp->getOpcode() == UnaryOperator::Deref) 978 return CheckAddressConstantExpression(Exp->getSubExpr()); 979 980 Diag(Init->getExprLoc(), 981 diag::err_init_element_not_constant, Init->getSourceRange()); 982 return true; 983 } 984 } 985} 986 987bool Sema::CheckAddressConstantExpression(const Expr* Init) { 988 switch (Init->getStmtClass()) { 989 default: 990 Diag(Init->getExprLoc(), 991 diag::err_init_element_not_constant, Init->getSourceRange()); 992 return true; 993 case Expr::ParenExprClass: 994 return CheckAddressConstantExpression(cast<ParenExpr>(Init)->getSubExpr()); 995 case Expr::StringLiteralClass: 996 case Expr::ObjCStringLiteralClass: 997 return false; 998 case Expr::CallExprClass: 999 // __builtin___CFStringMakeConstantString is a valid constant l-value. 1000 if (cast<CallExpr>(Init)->isBuiltinCall() == 1001 Builtin::BI__builtin___CFStringMakeConstantString) 1002 return false; 1003 1004 Diag(Init->getExprLoc(), 1005 diag::err_init_element_not_constant, Init->getSourceRange()); 1006 return true; 1007 1008 case Expr::UnaryOperatorClass: { 1009 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1010 1011 // C99 6.6p9 1012 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1013 return CheckAddressConstantExpressionLValue(Exp->getSubExpr()); 1014 1015 if (Exp->getOpcode() == UnaryOperator::Extension) 1016 return CheckAddressConstantExpression(Exp->getSubExpr()); 1017 1018 Diag(Init->getExprLoc(), 1019 diag::err_init_element_not_constant, Init->getSourceRange()); 1020 return true; 1021 } 1022 case Expr::BinaryOperatorClass: { 1023 // FIXME: Should we pedwarn for expressions like "a + 1 + 2"? 1024 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 1025 1026 Expr *PExp = Exp->getLHS(); 1027 Expr *IExp = Exp->getRHS(); 1028 if (IExp->getType()->isPointerType()) 1029 std::swap(PExp, IExp); 1030 1031 // FIXME: Should we pedwarn if IExp isn't an integer constant expression? 1032 return CheckAddressConstantExpression(PExp) || 1033 CheckArithmeticConstantExpression(IExp); 1034 } 1035 case Expr::ImplicitCastExprClass: 1036 case Expr::ExplicitCastExprClass: { 1037 const Expr* SubExpr = cast<CastExpr>(Init)->getSubExpr(); 1038 if (Init->getStmtClass() == Expr::ImplicitCastExprClass) { 1039 // Check for implicit promotion 1040 if (SubExpr->getType()->isFunctionType() || 1041 SubExpr->getType()->isArrayType()) 1042 return CheckAddressConstantExpressionLValue(SubExpr); 1043 } 1044 1045 // Check for pointer->pointer cast 1046 if (SubExpr->getType()->isPointerType()) 1047 return CheckAddressConstantExpression(SubExpr); 1048 1049 if (SubExpr->getType()->isIntegralType()) { 1050 // Check for the special-case of a pointer->int->pointer cast; 1051 // this isn't standard, but some code requires it. See 1052 // PR2720 for an example. 1053 if (const CastExpr* SubCast = dyn_cast<CastExpr>(SubExpr)) { 1054 if (SubCast->getSubExpr()->getType()->isPointerType()) { 1055 unsigned IntWidth = Context.getIntWidth(SubCast->getType()); 1056 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 1057 if (IntWidth >= PointerWidth) { 1058 return CheckAddressConstantExpression(SubCast->getSubExpr()); 1059 } 1060 } 1061 } 1062 } 1063 if (SubExpr->getType()->isArithmeticType()) { 1064 return CheckArithmeticConstantExpression(SubExpr); 1065 } 1066 1067 Diag(Init->getExprLoc(), 1068 diag::err_init_element_not_constant, Init->getSourceRange()); 1069 return true; 1070 } 1071 case Expr::ConditionalOperatorClass: { 1072 // FIXME: Should we pedwarn here? 1073 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 1074 if (!Exp->getCond()->getType()->isArithmeticType()) { 1075 Diag(Init->getExprLoc(), 1076 diag::err_init_element_not_constant, Init->getSourceRange()); 1077 return true; 1078 } 1079 if (CheckArithmeticConstantExpression(Exp->getCond())) 1080 return true; 1081 if (Exp->getLHS() && 1082 CheckAddressConstantExpression(Exp->getLHS())) 1083 return true; 1084 return CheckAddressConstantExpression(Exp->getRHS()); 1085 } 1086 case Expr::AddrLabelExprClass: 1087 return false; 1088 } 1089} 1090 1091static const Expr* FindExpressionBaseAddress(const Expr* E); 1092 1093static const Expr* FindExpressionBaseAddressLValue(const Expr* E) { 1094 switch (E->getStmtClass()) { 1095 default: 1096 return E; 1097 case Expr::ParenExprClass: { 1098 const ParenExpr* PE = cast<ParenExpr>(E); 1099 return FindExpressionBaseAddressLValue(PE->getSubExpr()); 1100 } 1101 case Expr::MemberExprClass: { 1102 const MemberExpr *M = cast<MemberExpr>(E); 1103 if (M->isArrow()) 1104 return FindExpressionBaseAddress(M->getBase()); 1105 return FindExpressionBaseAddressLValue(M->getBase()); 1106 } 1107 case Expr::ArraySubscriptExprClass: { 1108 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(E); 1109 return FindExpressionBaseAddress(ASE->getBase()); 1110 } 1111 case Expr::UnaryOperatorClass: { 1112 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1113 1114 if (Exp->getOpcode() == UnaryOperator::Deref) 1115 return FindExpressionBaseAddress(Exp->getSubExpr()); 1116 1117 return E; 1118 } 1119 } 1120} 1121 1122static const Expr* FindExpressionBaseAddress(const Expr* E) { 1123 switch (E->getStmtClass()) { 1124 default: 1125 return E; 1126 case Expr::ParenExprClass: { 1127 const ParenExpr* PE = cast<ParenExpr>(E); 1128 return FindExpressionBaseAddress(PE->getSubExpr()); 1129 } 1130 case Expr::UnaryOperatorClass: { 1131 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1132 1133 // C99 6.6p9 1134 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1135 return FindExpressionBaseAddressLValue(Exp->getSubExpr()); 1136 1137 if (Exp->getOpcode() == UnaryOperator::Extension) 1138 return FindExpressionBaseAddress(Exp->getSubExpr()); 1139 1140 return E; 1141 } 1142 case Expr::BinaryOperatorClass: { 1143 const BinaryOperator *Exp = cast<BinaryOperator>(E); 1144 1145 Expr *PExp = Exp->getLHS(); 1146 Expr *IExp = Exp->getRHS(); 1147 if (IExp->getType()->isPointerType()) 1148 std::swap(PExp, IExp); 1149 1150 return FindExpressionBaseAddress(PExp); 1151 } 1152 case Expr::ImplicitCastExprClass: { 1153 const Expr* SubExpr = cast<ImplicitCastExpr>(E)->getSubExpr(); 1154 1155 // Check for implicit promotion 1156 if (SubExpr->getType()->isFunctionType() || 1157 SubExpr->getType()->isArrayType()) 1158 return FindExpressionBaseAddressLValue(SubExpr); 1159 1160 // Check for pointer->pointer cast 1161 if (SubExpr->getType()->isPointerType()) 1162 return FindExpressionBaseAddress(SubExpr); 1163 1164 // We assume that we have an arithmetic expression here; 1165 // if we don't, we'll figure it out later 1166 return 0; 1167 } 1168 case Expr::ExplicitCastExprClass: { 1169 const Expr* SubExpr = cast<CastExpr>(E)->getSubExpr(); 1170 1171 // Check for pointer->pointer cast 1172 if (SubExpr->getType()->isPointerType()) 1173 return FindExpressionBaseAddress(SubExpr); 1174 1175 // We assume that we have an arithmetic expression here; 1176 // if we don't, we'll figure it out later 1177 return 0; 1178 } 1179 } 1180} 1181 1182bool Sema::CheckArithmeticConstantExpression(const Expr* Init) { 1183 switch (Init->getStmtClass()) { 1184 default: 1185 Diag(Init->getExprLoc(), 1186 diag::err_init_element_not_constant, Init->getSourceRange()); 1187 return true; 1188 case Expr::ParenExprClass: { 1189 const ParenExpr* PE = cast<ParenExpr>(Init); 1190 return CheckArithmeticConstantExpression(PE->getSubExpr()); 1191 } 1192 case Expr::FloatingLiteralClass: 1193 case Expr::IntegerLiteralClass: 1194 case Expr::CharacterLiteralClass: 1195 case Expr::ImaginaryLiteralClass: 1196 case Expr::TypesCompatibleExprClass: 1197 case Expr::CXXBoolLiteralExprClass: 1198 return false; 1199 case Expr::CallExprClass: { 1200 const CallExpr *CE = cast<CallExpr>(Init); 1201 1202 // Allow any constant foldable calls to builtins. 1203 if (CE->isBuiltinCall() && CE->isEvaluatable(Context)) 1204 return false; 1205 1206 Diag(Init->getExprLoc(), 1207 diag::err_init_element_not_constant, Init->getSourceRange()); 1208 return true; 1209 } 1210 case Expr::DeclRefExprClass: { 1211 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1212 if (isa<EnumConstantDecl>(D)) 1213 return false; 1214 Diag(Init->getExprLoc(), 1215 diag::err_init_element_not_constant, Init->getSourceRange()); 1216 return true; 1217 } 1218 case Expr::CompoundLiteralExprClass: 1219 // Allow "(vector type){2,4}"; normal C constraints don't allow this, 1220 // but vectors are allowed to be magic. 1221 if (Init->getType()->isVectorType()) 1222 return false; 1223 Diag(Init->getExprLoc(), 1224 diag::err_init_element_not_constant, Init->getSourceRange()); 1225 return true; 1226 case Expr::UnaryOperatorClass: { 1227 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1228 1229 switch (Exp->getOpcode()) { 1230 // Address, indirect, pre/post inc/dec, etc are not valid constant exprs. 1231 // See C99 6.6p3. 1232 default: 1233 Diag(Init->getExprLoc(), 1234 diag::err_init_element_not_constant, Init->getSourceRange()); 1235 return true; 1236 case UnaryOperator::SizeOf: 1237 case UnaryOperator::AlignOf: 1238 case UnaryOperator::OffsetOf: 1239 // sizeof(E) is a constantexpr if and only if E is not evaluted. 1240 // See C99 6.5.3.4p2 and 6.6p3. 1241 if (Exp->getSubExpr()->getType()->isConstantSizeType()) 1242 return false; 1243 Diag(Init->getExprLoc(), 1244 diag::err_init_element_not_constant, Init->getSourceRange()); 1245 return true; 1246 case UnaryOperator::Extension: 1247 case UnaryOperator::LNot: 1248 case UnaryOperator::Plus: 1249 case UnaryOperator::Minus: 1250 case UnaryOperator::Not: 1251 return CheckArithmeticConstantExpression(Exp->getSubExpr()); 1252 } 1253 } 1254 case Expr::SizeOfAlignOfTypeExprClass: { 1255 const SizeOfAlignOfTypeExpr *Exp = cast<SizeOfAlignOfTypeExpr>(Init); 1256 // Special check for void types, which are allowed as an extension 1257 if (Exp->getArgumentType()->isVoidType()) 1258 return false; 1259 // alignof always evaluates to a constant. 1260 // FIXME: is sizeof(int[3.0]) a constant expression? 1261 if (Exp->isSizeOf() && !Exp->getArgumentType()->isConstantSizeType()) { 1262 Diag(Init->getExprLoc(), 1263 diag::err_init_element_not_constant, Init->getSourceRange()); 1264 return true; 1265 } 1266 return false; 1267 } 1268 case Expr::BinaryOperatorClass: { 1269 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 1270 1271 if (Exp->getLHS()->getType()->isArithmeticType() && 1272 Exp->getRHS()->getType()->isArithmeticType()) { 1273 return CheckArithmeticConstantExpression(Exp->getLHS()) || 1274 CheckArithmeticConstantExpression(Exp->getRHS()); 1275 } 1276 1277 if (Exp->getLHS()->getType()->isPointerType() && 1278 Exp->getRHS()->getType()->isPointerType()) { 1279 const Expr* LHSBase = FindExpressionBaseAddress(Exp->getLHS()); 1280 const Expr* RHSBase = FindExpressionBaseAddress(Exp->getRHS()); 1281 1282 // Only allow a null (constant integer) base; we could 1283 // allow some additional cases if necessary, but this 1284 // is sufficient to cover offsetof-like constructs. 1285 if (!LHSBase && !RHSBase) { 1286 return CheckAddressConstantExpression(Exp->getLHS()) || 1287 CheckAddressConstantExpression(Exp->getRHS()); 1288 } 1289 } 1290 1291 Diag(Init->getExprLoc(), 1292 diag::err_init_element_not_constant, Init->getSourceRange()); 1293 return true; 1294 } 1295 case Expr::ImplicitCastExprClass: 1296 case Expr::ExplicitCastExprClass: { 1297 const Expr *SubExpr = cast<CastExpr>(Init)->getSubExpr(); 1298 if (SubExpr->getType()->isArithmeticType()) 1299 return CheckArithmeticConstantExpression(SubExpr); 1300 1301 if (SubExpr->getType()->isPointerType()) { 1302 const Expr* Base = FindExpressionBaseAddress(SubExpr); 1303 // If the pointer has a null base, this is an offsetof-like construct 1304 if (!Base) 1305 return CheckAddressConstantExpression(SubExpr); 1306 } 1307 1308 Diag(Init->getExprLoc(), 1309 diag::err_init_element_not_constant, Init->getSourceRange()); 1310 return true; 1311 } 1312 case Expr::ConditionalOperatorClass: { 1313 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 1314 1315 // If GNU extensions are disabled, we require all operands to be arithmetic 1316 // constant expressions. 1317 if (getLangOptions().NoExtensions) { 1318 return CheckArithmeticConstantExpression(Exp->getCond()) || 1319 (Exp->getLHS() && CheckArithmeticConstantExpression(Exp->getLHS())) || 1320 CheckArithmeticConstantExpression(Exp->getRHS()); 1321 } 1322 1323 // Otherwise, we have to emulate some of the behavior of fold here. 1324 // Basically GCC treats things like "4 ? 1 : somefunc()" as a constant 1325 // because it can constant fold things away. To retain compatibility with 1326 // GCC code, we see if we can fold the condition to a constant (which we 1327 // should always be able to do in theory). If so, we only require the 1328 // specified arm of the conditional to be a constant. This is a horrible 1329 // hack, but is require by real world code that uses __builtin_constant_p. 1330 APValue Val; 1331 if (!Exp->getCond()->tryEvaluate(Val, Context)) { 1332 // If the tryEvaluate couldn't fold it, CheckArithmeticConstantExpression 1333 // won't be able to either. Use it to emit the diagnostic though. 1334 bool Res = CheckArithmeticConstantExpression(Exp->getCond()); 1335 assert(Res && "tryEvaluate couldn't evaluate this constant?"); 1336 return Res; 1337 } 1338 1339 // Verify that the side following the condition is also a constant. 1340 const Expr *TrueSide = Exp->getLHS(), *FalseSide = Exp->getRHS(); 1341 if (Val.getInt() == 0) 1342 std::swap(TrueSide, FalseSide); 1343 1344 if (TrueSide && CheckArithmeticConstantExpression(TrueSide)) 1345 return true; 1346 1347 // Okay, the evaluated side evaluates to a constant, so we accept this. 1348 // Check to see if the other side is obviously not a constant. If so, 1349 // emit a warning that this is a GNU extension. 1350 if (FalseSide && !FalseSide->isEvaluatable(Context)) 1351 Diag(Init->getExprLoc(), 1352 diag::ext_typecheck_expression_not_constant_but_accepted, 1353 FalseSide->getSourceRange()); 1354 return false; 1355 } 1356 } 1357} 1358 1359bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 1360 Init = Init->IgnoreParens(); 1361 1362 // Look through CXXDefaultArgExprs; they have no meaning in this context. 1363 if (CXXDefaultArgExpr* DAE = dyn_cast<CXXDefaultArgExpr>(Init)) 1364 return CheckForConstantInitializer(DAE->getExpr(), DclT); 1365 1366 if (CompoundLiteralExpr *e = dyn_cast<CompoundLiteralExpr>(Init)) 1367 return CheckForConstantInitializer(e->getInitializer(), DclT); 1368 1369 if (Init->getType()->isReferenceType()) { 1370 // FIXME: Work out how the heck references work. 1371 return false; 1372 } 1373 1374 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 1375 unsigned numInits = Exp->getNumInits(); 1376 for (unsigned i = 0; i < numInits; i++) { 1377 // FIXME: Need to get the type of the declaration for C++, 1378 // because it could be a reference? 1379 if (CheckForConstantInitializer(Exp->getInit(i), 1380 Exp->getInit(i)->getType())) 1381 return true; 1382 } 1383 return false; 1384 } 1385 1386 if (Init->isNullPointerConstant(Context)) 1387 return false; 1388 if (Init->getType()->isArithmeticType()) { 1389 QualType InitTy = Context.getCanonicalType(Init->getType()) 1390 .getUnqualifiedType(); 1391 if (InitTy == Context.BoolTy) { 1392 // Special handling for pointers implicitly cast to bool; 1393 // (e.g. "_Bool rr = &rr;"). This is only legal at the top level. 1394 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Init)) { 1395 Expr* SubE = ICE->getSubExpr(); 1396 if (SubE->getType()->isPointerType() || 1397 SubE->getType()->isArrayType() || 1398 SubE->getType()->isFunctionType()) { 1399 return CheckAddressConstantExpression(Init); 1400 } 1401 } 1402 } else if (InitTy->isIntegralType()) { 1403 Expr* SubE = 0; 1404 if (CastExpr* CE = dyn_cast<CastExpr>(Init)) 1405 SubE = CE->getSubExpr(); 1406 // Special check for pointer cast to int; we allow as an extension 1407 // an address constant cast to an integer if the integer 1408 // is of an appropriate width (this sort of code is apparently used 1409 // in some places). 1410 // FIXME: Add pedwarn? 1411 // FIXME: Don't allow bitfields here! Need the FieldDecl for that. 1412 if (SubE && (SubE->getType()->isPointerType() || 1413 SubE->getType()->isArrayType() || 1414 SubE->getType()->isFunctionType())) { 1415 unsigned IntWidth = Context.getTypeSize(Init->getType()); 1416 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 1417 if (IntWidth >= PointerWidth) 1418 return CheckAddressConstantExpression(Init); 1419 } 1420 } 1421 1422 return CheckArithmeticConstantExpression(Init); 1423 } 1424 1425 if (Init->getType()->isPointerType()) 1426 return CheckAddressConstantExpression(Init); 1427 1428 // An array type at the top level that isn't an init-list must 1429 // be a string literal 1430 if (Init->getType()->isArrayType()) 1431 return false; 1432 1433 if (Init->getType()->isFunctionType()) 1434 return false; 1435 1436 // Allow block exprs at top level. 1437 if (Init->getType()->isBlockPointerType()) 1438 return false; 1439 1440 Diag(Init->getExprLoc(), diag::err_init_element_not_constant, 1441 Init->getSourceRange()); 1442 return true; 1443} 1444 1445void Sema::AddInitializerToDecl(DeclTy *dcl, ExprTy *init) { 1446 Decl *RealDecl = static_cast<Decl *>(dcl); 1447 Expr *Init = static_cast<Expr *>(init); 1448 assert(Init && "missing initializer"); 1449 1450 // If there is no declaration, there was an error parsing it. Just ignore 1451 // the initializer. 1452 if (RealDecl == 0) { 1453 delete Init; 1454 return; 1455 } 1456 1457 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 1458 if (!VDecl) { 1459 Diag(dyn_cast<ScopedDecl>(RealDecl)->getLocation(), 1460 diag::err_illegal_initializer); 1461 RealDecl->setInvalidDecl(); 1462 return; 1463 } 1464 // Get the decls type and save a reference for later, since 1465 // CheckInitializerTypes may change it. 1466 QualType DclT = VDecl->getType(), SavT = DclT; 1467 if (VDecl->isBlockVarDecl()) { 1468 VarDecl::StorageClass SC = VDecl->getStorageClass(); 1469 if (SC == VarDecl::Extern) { // C99 6.7.8p5 1470 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 1471 VDecl->setInvalidDecl(); 1472 } else if (!VDecl->isInvalidDecl()) { 1473 if (CheckInitializerTypes(Init, DclT)) 1474 VDecl->setInvalidDecl(); 1475 1476 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 1477 if (!getLangOptions().CPlusPlus) { 1478 if (SC == VarDecl::Static) // C99 6.7.8p4. 1479 CheckForConstantInitializer(Init, DclT); 1480 } 1481 } 1482 } else if (VDecl->isFileVarDecl()) { 1483 if (VDecl->getStorageClass() == VarDecl::Extern) 1484 Diag(VDecl->getLocation(), diag::warn_extern_init); 1485 if (!VDecl->isInvalidDecl()) 1486 if (CheckInitializerTypes(Init, DclT)) 1487 VDecl->setInvalidDecl(); 1488 1489 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 1490 if (!getLangOptions().CPlusPlus) { 1491 // C99 6.7.8p4. All file scoped initializers need to be constant. 1492 CheckForConstantInitializer(Init, DclT); 1493 } 1494 } 1495 // If the type changed, it means we had an incomplete type that was 1496 // completed by the initializer. For example: 1497 // int ary[] = { 1, 3, 5 }; 1498 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 1499 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 1500 VDecl->setType(DclT); 1501 Init->setType(DclT); 1502 } 1503 1504 // Attach the initializer to the decl. 1505 VDecl->setInit(Init); 1506 return; 1507} 1508 1509/// The declarators are chained together backwards, reverse the list. 1510Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 1511 // Often we have single declarators, handle them quickly. 1512 Decl *GroupDecl = static_cast<Decl*>(group); 1513 if (GroupDecl == 0) 1514 return 0; 1515 1516 ScopedDecl *Group = dyn_cast<ScopedDecl>(GroupDecl); 1517 ScopedDecl *NewGroup = 0; 1518 if (Group->getNextDeclarator() == 0) 1519 NewGroup = Group; 1520 else { // reverse the list. 1521 while (Group) { 1522 ScopedDecl *Next = Group->getNextDeclarator(); 1523 Group->setNextDeclarator(NewGroup); 1524 NewGroup = Group; 1525 Group = Next; 1526 } 1527 } 1528 // Perform semantic analysis that depends on having fully processed both 1529 // the declarator and initializer. 1530 for (ScopedDecl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 1531 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 1532 if (!IDecl) 1533 continue; 1534 QualType T = IDecl->getType(); 1535 1536 // C99 6.7.5.2p2: If an identifier is declared to be an object with 1537 // static storage duration, it shall not have a variable length array. 1538 if ((IDecl->isFileVarDecl() || IDecl->isBlockVarDecl()) && 1539 IDecl->getStorageClass() == VarDecl::Static) { 1540 if (T->isVariableArrayType()) { 1541 Diag(IDecl->getLocation(), diag::err_typecheck_illegal_vla); 1542 IDecl->setInvalidDecl(); 1543 } 1544 } 1545 // Block scope. C99 6.7p7: If an identifier for an object is declared with 1546 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 1547 if (IDecl->isBlockVarDecl() && 1548 IDecl->getStorageClass() != VarDecl::Extern) { 1549 if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 1550 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type, 1551 T.getAsString()); 1552 IDecl->setInvalidDecl(); 1553 } 1554 } 1555 // File scope. C99 6.9.2p2: A declaration of an identifier for and 1556 // object that has file scope without an initializer, and without a 1557 // storage-class specifier or with the storage-class specifier "static", 1558 // constitutes a tentative definition. Note: A tentative definition with 1559 // external linkage is valid (C99 6.2.2p5). 1560 if (isTentativeDefinition(IDecl)) { 1561 if (T->isIncompleteArrayType()) { 1562 // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete 1563 // array to be completed. Don't issue a diagnostic. 1564 } else if (T->isIncompleteType() && !IDecl->isInvalidDecl()) { 1565 // C99 6.9.2p3: If the declaration of an identifier for an object is 1566 // a tentative definition and has internal linkage (C99 6.2.2p3), the 1567 // declared type shall not be an incomplete type. 1568 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type, 1569 T.getAsString()); 1570 IDecl->setInvalidDecl(); 1571 } 1572 } 1573 if (IDecl->isFileVarDecl()) 1574 CheckForFileScopedRedefinitions(S, IDecl); 1575 } 1576 return NewGroup; 1577} 1578 1579/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 1580/// to introduce parameters into function prototype scope. 1581Sema::DeclTy * 1582Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 1583 const DeclSpec &DS = D.getDeclSpec(); 1584 1585 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 1586 VarDecl::StorageClass StorageClass = VarDecl::None; 1587 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 1588 StorageClass = VarDecl::Register; 1589 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 1590 Diag(DS.getStorageClassSpecLoc(), 1591 diag::err_invalid_storage_class_in_func_decl); 1592 D.getMutableDeclSpec().ClearStorageClassSpecs(); 1593 } 1594 if (DS.isThreadSpecified()) { 1595 Diag(DS.getThreadSpecLoc(), 1596 diag::err_invalid_storage_class_in_func_decl); 1597 D.getMutableDeclSpec().ClearStorageClassSpecs(); 1598 } 1599 1600 // Check that there are no default arguments inside the type of this 1601 // parameter (C++ only). 1602 if (getLangOptions().CPlusPlus) 1603 CheckExtraCXXDefaultArguments(D); 1604 1605 // In this context, we *do not* check D.getInvalidType(). If the declarator 1606 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 1607 // though it will not reflect the user specified type. 1608 QualType parmDeclType = GetTypeForDeclarator(D, S); 1609 1610 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 1611 1612 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 1613 // Can this happen for params? We already checked that they don't conflict 1614 // among each other. Here they can only shadow globals, which is ok. 1615 IdentifierInfo *II = D.getIdentifier(); 1616 if (Decl *PrevDecl = LookupDecl(II, Decl::IDNS_Ordinary, S)) { 1617 if (S->isDeclScope(PrevDecl)) { 1618 Diag(D.getIdentifierLoc(), diag::err_param_redefinition, 1619 dyn_cast<NamedDecl>(PrevDecl)->getName()); 1620 1621 // Recover by removing the name 1622 II = 0; 1623 D.SetIdentifier(0, D.getIdentifierLoc()); 1624 } 1625 } 1626 1627 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 1628 // Doing the promotion here has a win and a loss. The win is the type for 1629 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 1630 // code generator). The loss is the orginal type isn't preserved. For example: 1631 // 1632 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 1633 // int blockvardecl[5]; 1634 // sizeof(parmvardecl); // size == 4 1635 // sizeof(blockvardecl); // size == 20 1636 // } 1637 // 1638 // For expressions, all implicit conversions are captured using the 1639 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 1640 // 1641 // FIXME: If a source translation tool needs to see the original type, then 1642 // we need to consider storing both types (in ParmVarDecl)... 1643 // 1644 if (parmDeclType->isArrayType()) { 1645 // int x[restrict 4] -> int *restrict 1646 parmDeclType = Context.getArrayDecayedType(parmDeclType); 1647 } else if (parmDeclType->isFunctionType()) 1648 parmDeclType = Context.getPointerType(parmDeclType); 1649 1650 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 1651 D.getIdentifierLoc(), II, 1652 parmDeclType, StorageClass, 1653 0, 0); 1654 1655 if (D.getInvalidType()) 1656 New->setInvalidDecl(); 1657 1658 if (II) 1659 PushOnScopeChains(New, S); 1660 1661 ProcessDeclAttributes(New, D); 1662 return New; 1663 1664} 1665 1666Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 1667 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 1668 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 1669 "Not a function declarator!"); 1670 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1671 1672 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 1673 // for a K&R function. 1674 if (!FTI.hasPrototype) { 1675 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 1676 if (FTI.ArgInfo[i].Param == 0) { 1677 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared, 1678 FTI.ArgInfo[i].Ident->getName()); 1679 // Implicitly declare the argument as type 'int' for lack of a better 1680 // type. 1681 DeclSpec DS; 1682 const char* PrevSpec; // unused 1683 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 1684 PrevSpec); 1685 Declarator ParamD(DS, Declarator::KNRTypeListContext); 1686 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 1687 FTI.ArgInfo[i].Param = ActOnParamDeclarator(FnBodyScope, ParamD); 1688 } 1689 } 1690 } else { 1691 // FIXME: Diagnose arguments without names in C. 1692 } 1693 1694 Scope *GlobalScope = FnBodyScope->getParent(); 1695 1696 // See if this is a redefinition. 1697 Decl *PrevDcl = LookupDecl(D.getIdentifier(), Decl::IDNS_Ordinary, 1698 GlobalScope); 1699 if (PrevDcl && isDeclInScope(PrevDcl, CurContext)) { 1700 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(PrevDcl)) { 1701 const FunctionDecl *Definition; 1702 if (FD->getBody(Definition)) { 1703 Diag(D.getIdentifierLoc(), diag::err_redefinition, 1704 D.getIdentifier()->getName()); 1705 Diag(Definition->getLocation(), diag::err_previous_definition); 1706 } 1707 } 1708 } 1709 1710 return ActOnStartOfFunctionDef(FnBodyScope, 1711 ActOnDeclarator(GlobalScope, D, 0)); 1712} 1713 1714Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclTy *D) { 1715 Decl *decl = static_cast<Decl*>(D); 1716 FunctionDecl *FD = cast<FunctionDecl>(decl); 1717 PushDeclContext(FD); 1718 1719 // Check the validity of our function parameters 1720 CheckParmsForFunctionDef(FD); 1721 1722 // Introduce our parameters into the function scope 1723 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1724 ParmVarDecl *Param = FD->getParamDecl(p); 1725 // If this has an identifier, add it to the scope stack. 1726 if (Param->getIdentifier()) 1727 PushOnScopeChains(Param, FnBodyScope); 1728 } 1729 1730 return FD; 1731} 1732 1733Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtTy *Body) { 1734 Decl *dcl = static_cast<Decl *>(D); 1735 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 1736 FD->setBody((Stmt*)Body); 1737 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 1738 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 1739 MD->setBody((Stmt*)Body); 1740 } else 1741 return 0; 1742 PopDeclContext(); 1743 // Verify and clean out per-function state. 1744 1745 // Check goto/label use. 1746 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 1747 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 1748 // Verify that we have no forward references left. If so, there was a goto 1749 // or address of a label taken, but no definition of it. Label fwd 1750 // definitions are indicated with a null substmt. 1751 if (I->second->getSubStmt() == 0) { 1752 LabelStmt *L = I->second; 1753 // Emit error. 1754 Diag(L->getIdentLoc(), diag::err_undeclared_label_use, L->getName()); 1755 1756 // At this point, we have gotos that use the bogus label. Stitch it into 1757 // the function body so that they aren't leaked and that the AST is well 1758 // formed. 1759 if (Body) { 1760 L->setSubStmt(new NullStmt(L->getIdentLoc())); 1761 cast<CompoundStmt>((Stmt*)Body)->push_back(L); 1762 } else { 1763 // The whole function wasn't parsed correctly, just delete this. 1764 delete L; 1765 } 1766 } 1767 } 1768 LabelMap.clear(); 1769 1770 return D; 1771} 1772 1773/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 1774/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 1775ScopedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 1776 IdentifierInfo &II, Scope *S) { 1777 // Extension in C99. Legal in C90, but warn about it. 1778 if (getLangOptions().C99) 1779 Diag(Loc, diag::ext_implicit_function_decl, II.getName()); 1780 else 1781 Diag(Loc, diag::warn_implicit_function_decl, II.getName()); 1782 1783 // FIXME: handle stuff like: 1784 // void foo() { extern float X(); } 1785 // void bar() { X(); } <-- implicit decl for X in another scope. 1786 1787 // Set a Declarator for the implicit definition: int foo(); 1788 const char *Dummy; 1789 DeclSpec DS; 1790 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 1791 Error = Error; // Silence warning. 1792 assert(!Error && "Error setting up implicit decl!"); 1793 Declarator D(DS, Declarator::BlockContext); 1794 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, 0, 0, Loc)); 1795 D.SetIdentifier(&II, Loc); 1796 1797 // Insert this function into translation-unit scope. 1798 1799 DeclContext *PrevDC = CurContext; 1800 CurContext = Context.getTranslationUnitDecl(); 1801 1802 FunctionDecl *FD = 1803 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 1804 FD->setImplicit(); 1805 1806 CurContext = PrevDC; 1807 1808 return FD; 1809} 1810 1811 1812TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 1813 ScopedDecl *LastDeclarator) { 1814 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 1815 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 1816 1817 // Scope manipulation handled by caller. 1818 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 1819 D.getIdentifierLoc(), 1820 D.getIdentifier(), 1821 T, LastDeclarator); 1822 if (D.getInvalidType()) 1823 NewTD->setInvalidDecl(); 1824 return NewTD; 1825} 1826 1827/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 1828/// former case, Name will be non-null. In the later case, Name will be null. 1829/// TagType indicates what kind of tag this is. TK indicates whether this is a 1830/// reference/declaration/definition of a tag. 1831Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagType, TagKind TK, 1832 SourceLocation KWLoc, IdentifierInfo *Name, 1833 SourceLocation NameLoc, AttributeList *Attr) { 1834 // If this is a use of an existing tag, it must have a name. 1835 assert((Name != 0 || TK == TK_Definition) && 1836 "Nameless record must be a definition!"); 1837 1838 TagDecl::TagKind Kind; 1839 switch (TagType) { 1840 default: assert(0 && "Unknown tag type!"); 1841 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 1842 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 1843 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 1844 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 1845 } 1846 1847 // Two code paths: a new one for structs/unions/classes where we create 1848 // separate decls for forward declarations, and an old (eventually to 1849 // be removed) code path for enums. 1850 if (Kind != TagDecl::TK_enum) 1851 return ActOnTagStruct(S, Kind, TK, KWLoc, Name, NameLoc, Attr); 1852 1853 // If this is a named struct, check to see if there was a previous forward 1854 // declaration or definition. 1855 // Use ScopedDecl instead of TagDecl, because a NamespaceDecl may come up. 1856 ScopedDecl *PrevDecl = 1857 dyn_cast_or_null<ScopedDecl>(LookupDecl(Name, Decl::IDNS_Tag, S)); 1858 1859 if (PrevDecl) { 1860 assert((isa<TagDecl>(PrevDecl) || isa<NamespaceDecl>(PrevDecl)) && 1861 "unexpected Decl type"); 1862 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 1863 // If this is a use of a previous tag, or if the tag is already declared 1864 // in the same scope (so that the definition/declaration completes or 1865 // rementions the tag), reuse the decl. 1866 if (TK == TK_Reference || isDeclInScope(PrevDecl, CurContext, S)) { 1867 // Make sure that this wasn't declared as an enum and now used as a 1868 // struct or something similar. 1869 if (PrevTagDecl->getTagKind() != Kind) { 1870 Diag(KWLoc, diag::err_use_with_wrong_tag, Name->getName()); 1871 Diag(PrevDecl->getLocation(), diag::err_previous_use); 1872 // Recover by making this an anonymous redefinition. 1873 Name = 0; 1874 PrevDecl = 0; 1875 } else { 1876 // If this is a use or a forward declaration, we're good. 1877 if (TK != TK_Definition) 1878 return PrevDecl; 1879 1880 // Diagnose attempts to redefine a tag. 1881 if (PrevTagDecl->isDefinition()) { 1882 Diag(NameLoc, diag::err_redefinition, Name->getName()); 1883 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 1884 // If this is a redefinition, recover by making this struct be 1885 // anonymous, which will make any later references get the previous 1886 // definition. 1887 Name = 0; 1888 } else { 1889 // Okay, this is definition of a previously declared or referenced 1890 // tag. Move the location of the decl to be the definition site. 1891 PrevDecl->setLocation(NameLoc); 1892 return PrevDecl; 1893 } 1894 } 1895 } 1896 // If we get here, this is a definition of a new struct type in a nested 1897 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a new 1898 // type. 1899 } else { 1900 // PrevDecl is a namespace. 1901 if (isDeclInScope(PrevDecl, CurContext, S)) { 1902 // The tag name clashes with a namespace name, issue an error and 1903 // recover by making this tag be anonymous. 1904 Diag(NameLoc, diag::err_redefinition_different_kind, Name->getName()); 1905 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 1906 Name = 0; 1907 } 1908 } 1909 } 1910 1911 // If there is an identifier, use the location of the identifier as the 1912 // location of the decl, otherwise use the location of the struct/union 1913 // keyword. 1914 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 1915 1916 // Otherwise, if this is the first time we've seen this tag, create the decl. 1917 TagDecl *New; 1918 if (Kind == TagDecl::TK_enum) { 1919 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 1920 // enum X { A, B, C } D; D should chain to X. 1921 New = EnumDecl::Create(Context, CurContext, Loc, Name, 0); 1922 // If this is an undefined enum, warn. 1923 if (TK != TK_Definition) Diag(Loc, diag::ext_forward_ref_enum); 1924 } else { 1925 // struct/union/class 1926 1927 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 1928 // struct X { int A; } D; D should chain to X. 1929 if (getLangOptions().CPlusPlus) 1930 // FIXME: Look for a way to use RecordDecl for simple structs. 1931 New = CXXRecordDecl::Create(Context, Kind, CurContext, Loc, Name); 1932 else 1933 New = RecordDecl::Create(Context, Kind, CurContext, Loc, Name); 1934 } 1935 1936 // If this has an identifier, add it to the scope stack. 1937 if (Name) { 1938 // The scope passed in may not be a decl scope. Zip up the scope tree until 1939 // we find one that is. 1940 while ((S->getFlags() & Scope::DeclScope) == 0) 1941 S = S->getParent(); 1942 1943 // Add it to the decl chain. 1944 PushOnScopeChains(New, S); 1945 } 1946 1947 if (Attr) 1948 ProcessDeclAttributeList(New, Attr); 1949 return New; 1950} 1951 1952/// ActOnTagStruct - New "ActOnTag" logic for structs/unions/classes. Unlike 1953/// the logic for enums, we create separate decls for forward declarations. 1954/// This is called by ActOnTag, but eventually will replace its logic. 1955Sema::DeclTy *Sema::ActOnTagStruct(Scope *S, TagDecl::TagKind Kind, TagKind TK, 1956 SourceLocation KWLoc, IdentifierInfo *Name, 1957 SourceLocation NameLoc, AttributeList *Attr) { 1958 1959 // If this is a named struct, check to see if there was a previous forward 1960 // declaration or definition. 1961 // Use ScopedDecl instead of TagDecl, because a NamespaceDecl may come up. 1962 ScopedDecl *PrevDecl = 1963 dyn_cast_or_null<ScopedDecl>(LookupDecl(Name, Decl::IDNS_Tag, S)); 1964 1965 if (PrevDecl) { 1966 assert((isa<TagDecl>(PrevDecl) || isa<NamespaceDecl>(PrevDecl)) && 1967 "unexpected Decl type"); 1968 1969 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 1970 // If this is a use of a previous tag, or if the tag is already declared 1971 // in the same scope (so that the definition/declaration completes or 1972 // rementions the tag), reuse the decl. 1973 if (TK == TK_Reference || isDeclInScope(PrevDecl, CurContext, S)) { 1974 // Make sure that this wasn't declared as an enum and now used as a 1975 // struct or something similar. 1976 if (PrevTagDecl->getTagKind() != Kind) { 1977 Diag(KWLoc, diag::err_use_with_wrong_tag, Name->getName()); 1978 Diag(PrevDecl->getLocation(), diag::err_previous_use); 1979 // Recover by making this an anonymous redefinition. 1980 Name = 0; 1981 PrevDecl = 0; 1982 } else { 1983 // If this is a use, return the original decl. 1984 1985 // FIXME: In the future, return a variant or some other clue 1986 // for the consumer of this Decl to know it doesn't own it. 1987 // For our current ASTs this shouldn't be a problem, but will 1988 // need to be changed with DeclGroups. 1989 if (TK == TK_Reference) 1990 return PrevDecl; 1991 1992 // The new decl is a definition? 1993 if (TK == TK_Definition) { 1994 // Diagnose attempts to redefine a tag. 1995 if (RecordDecl* DefRecord = 1996 cast<RecordDecl>(PrevTagDecl)->getDefinition(Context)) { 1997 Diag(NameLoc, diag::err_redefinition, Name->getName()); 1998 Diag(DefRecord->getLocation(), diag::err_previous_definition); 1999 // If this is a redefinition, recover by making this struct be 2000 // anonymous, which will make any later references get the previous 2001 // definition. 2002 Name = 0; 2003 PrevDecl = 0; 2004 } 2005 // Okay, this is definition of a previously declared or referenced 2006 // tag. We're going to create a new Decl. 2007 } 2008 } 2009 // If we get here we have (another) forward declaration. Just create 2010 // a new decl. 2011 } 2012 else { 2013 // If we get here, this is a definition of a new struct type in a nested 2014 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 2015 // new decl/type. We set PrevDecl to NULL so that the Records 2016 // have distinct types. 2017 PrevDecl = 0; 2018 } 2019 } else { 2020 // PrevDecl is a namespace. 2021 if (isDeclInScope(PrevDecl, CurContext, S)) { 2022 // The tag name clashes with a namespace name, issue an error and 2023 // recover by making this tag be anonymous. 2024 Diag(NameLoc, diag::err_redefinition_different_kind, Name->getName()); 2025 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 2026 Name = 0; 2027 } 2028 } 2029 } 2030 2031 // If there is an identifier, use the location of the identifier as the 2032 // location of the decl, otherwise use the location of the struct/union 2033 // keyword. 2034 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 2035 2036 // Otherwise, if this is the first time we've seen this tag, create the decl. 2037 TagDecl *New; 2038 2039 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 2040 // struct X { int A; } D; D should chain to X. 2041 if (getLangOptions().CPlusPlus) 2042 // FIXME: Look for a way to use RecordDecl for simple structs. 2043 New = CXXRecordDecl::Create(Context, Kind, CurContext, Loc, Name, 2044 dyn_cast_or_null<CXXRecordDecl>(PrevDecl)); 2045 else 2046 New = RecordDecl::Create(Context, Kind, CurContext, Loc, Name, 2047 dyn_cast_or_null<RecordDecl>(PrevDecl)); 2048 2049 // If this has an identifier, add it to the scope stack. 2050 if ((TK == TK_Definition || !PrevDecl) && Name) { 2051 // The scope passed in may not be a decl scope. Zip up the scope tree until 2052 // we find one that is. 2053 while ((S->getFlags() & Scope::DeclScope) == 0) 2054 S = S->getParent(); 2055 2056 // Add it to the decl chain. 2057 PushOnScopeChains(New, S); 2058 } 2059 2060 // Handle #pragma pack: if the #pragma pack stack has non-default 2061 // alignment, make up a packed attribute for this decl. These 2062 // attributes are checked when the ASTContext lays out the 2063 // structure. 2064 // 2065 // It is important for implementing the correct semantics that this 2066 // happen here (in act on tag decl). The #pragma pack stack is 2067 // maintained as a result of parser callbacks which can occur at 2068 // many points during the parsing of a struct declaration (because 2069 // the #pragma tokens are effectively skipped over during the 2070 // parsing of the struct). 2071 if (unsigned Alignment = PackContext.getAlignment()) 2072 New->addAttr(new PackedAttr(Alignment * 8)); 2073 2074 if (Attr) 2075 ProcessDeclAttributeList(New, Attr); 2076 2077 return New; 2078} 2079 2080 2081/// Collect the instance variables declared in an Objective-C object. Used in 2082/// the creation of structures from objects using the @defs directive. 2083static void CollectIvars(ObjCInterfaceDecl *Class, ASTContext& Ctx, 2084 llvm::SmallVectorImpl<Sema::DeclTy*> &ivars) { 2085 if (Class->getSuperClass()) 2086 CollectIvars(Class->getSuperClass(), Ctx, ivars); 2087 2088 // For each ivar, create a fresh ObjCAtDefsFieldDecl. 2089 for (ObjCInterfaceDecl::ivar_iterator 2090 I=Class->ivar_begin(), E=Class->ivar_end(); I!=E; ++I) { 2091 2092 ObjCIvarDecl* ID = *I; 2093 ivars.push_back(ObjCAtDefsFieldDecl::Create(Ctx, ID->getLocation(), 2094 ID->getIdentifier(), 2095 ID->getType(), 2096 ID->getBitWidth())); 2097 } 2098} 2099 2100/// Called whenever @defs(ClassName) is encountered in the source. Inserts the 2101/// instance variables of ClassName into Decls. 2102void Sema::ActOnDefs(Scope *S, SourceLocation DeclStart, 2103 IdentifierInfo *ClassName, 2104 llvm::SmallVectorImpl<DeclTy*> &Decls) { 2105 // Check that ClassName is a valid class 2106 ObjCInterfaceDecl *Class = getObjCInterfaceDecl(ClassName); 2107 if (!Class) { 2108 Diag(DeclStart, diag::err_undef_interface, ClassName->getName()); 2109 return; 2110 } 2111 // Collect the instance variables 2112 CollectIvars(Class, Context, Decls); 2113} 2114 2115QualType Sema::TryFixInvalidVariablyModifiedType(QualType T) { 2116 // This method tries to turn a variable array into a constant 2117 // array even when the size isn't an ICE. This is necessary 2118 // for compatibility with code that depends on gcc's buggy 2119 // constant expression folding, like struct {char x[(int)(char*)2];} 2120 if (const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T)) { 2121 APValue Result; 2122 if (VLATy->getSizeExpr() && 2123 VLATy->getSizeExpr()->tryEvaluate(Result, Context) && Result.isInt()) { 2124 llvm::APSInt &Res = Result.getInt(); 2125 if (Res > llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 2126 return Context.getConstantArrayType(VLATy->getElementType(), 2127 Res, ArrayType::Normal, 0); 2128 } 2129 } 2130 return QualType(); 2131} 2132 2133/// ActOnField - Each field of a struct/union/class is passed into this in order 2134/// to create a FieldDecl object for it. 2135Sema::DeclTy *Sema::ActOnField(Scope *S, 2136 SourceLocation DeclStart, 2137 Declarator &D, ExprTy *BitfieldWidth) { 2138 IdentifierInfo *II = D.getIdentifier(); 2139 Expr *BitWidth = (Expr*)BitfieldWidth; 2140 SourceLocation Loc = DeclStart; 2141 if (II) Loc = D.getIdentifierLoc(); 2142 2143 // FIXME: Unnamed fields can be handled in various different ways, for 2144 // example, unnamed unions inject all members into the struct namespace! 2145 2146 if (BitWidth) { 2147 // TODO: Validate. 2148 //printf("WARNING: BITFIELDS IGNORED!\n"); 2149 2150 // 6.7.2.1p3 2151 // 6.7.2.1p4 2152 2153 } else { 2154 // Not a bitfield. 2155 2156 // validate II. 2157 2158 } 2159 2160 QualType T = GetTypeForDeclarator(D, S); 2161 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 2162 bool InvalidDecl = false; 2163 2164 // C99 6.7.2.1p8: A member of a structure or union may have any type other 2165 // than a variably modified type. 2166 if (T->isVariablyModifiedType()) { 2167 QualType FixedTy = TryFixInvalidVariablyModifiedType(T); 2168 if (!FixedTy.isNull()) { 2169 Diag(Loc, diag::warn_illegal_constant_array_size, Loc); 2170 T = FixedTy; 2171 } else { 2172 // FIXME: This diagnostic needs work 2173 Diag(Loc, diag::err_typecheck_illegal_vla, Loc); 2174 InvalidDecl = true; 2175 } 2176 } 2177 // FIXME: Chain fielddecls together. 2178 FieldDecl *NewFD; 2179 2180 if (getLangOptions().CPlusPlus) { 2181 // FIXME: Replace CXXFieldDecls with FieldDecls for simple structs. 2182 NewFD = CXXFieldDecl::Create(Context, cast<CXXRecordDecl>(CurContext), 2183 Loc, II, T, BitWidth); 2184 if (II) 2185 PushOnScopeChains(NewFD, S); 2186 } 2187 else 2188 NewFD = FieldDecl::Create(Context, Loc, II, T, BitWidth); 2189 2190 ProcessDeclAttributes(NewFD, D); 2191 2192 if (D.getInvalidType() || InvalidDecl) 2193 NewFD->setInvalidDecl(); 2194 return NewFD; 2195} 2196 2197/// TranslateIvarVisibility - Translate visibility from a token ID to an 2198/// AST enum value. 2199static ObjCIvarDecl::AccessControl 2200TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 2201 switch (ivarVisibility) { 2202 default: assert(0 && "Unknown visitibility kind"); 2203 case tok::objc_private: return ObjCIvarDecl::Private; 2204 case tok::objc_public: return ObjCIvarDecl::Public; 2205 case tok::objc_protected: return ObjCIvarDecl::Protected; 2206 case tok::objc_package: return ObjCIvarDecl::Package; 2207 } 2208} 2209 2210/// ActOnIvar - Each ivar field of an objective-c class is passed into this 2211/// in order to create an IvarDecl object for it. 2212Sema::DeclTy *Sema::ActOnIvar(Scope *S, 2213 SourceLocation DeclStart, 2214 Declarator &D, ExprTy *BitfieldWidth, 2215 tok::ObjCKeywordKind Visibility) { 2216 IdentifierInfo *II = D.getIdentifier(); 2217 Expr *BitWidth = (Expr*)BitfieldWidth; 2218 SourceLocation Loc = DeclStart; 2219 if (II) Loc = D.getIdentifierLoc(); 2220 2221 // FIXME: Unnamed fields can be handled in various different ways, for 2222 // example, unnamed unions inject all members into the struct namespace! 2223 2224 2225 if (BitWidth) { 2226 // TODO: Validate. 2227 //printf("WARNING: BITFIELDS IGNORED!\n"); 2228 2229 // 6.7.2.1p3 2230 // 6.7.2.1p4 2231 2232 } else { 2233 // Not a bitfield. 2234 2235 // validate II. 2236 2237 } 2238 2239 QualType T = GetTypeForDeclarator(D, S); 2240 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 2241 bool InvalidDecl = false; 2242 2243 // C99 6.7.2.1p8: A member of a structure or union may have any type other 2244 // than a variably modified type. 2245 if (T->isVariablyModifiedType()) { 2246 // FIXME: This diagnostic needs work 2247 Diag(Loc, diag::err_typecheck_illegal_vla, Loc); 2248 InvalidDecl = true; 2249 } 2250 2251 // Get the visibility (access control) for this ivar. 2252 ObjCIvarDecl::AccessControl ac = 2253 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 2254 : ObjCIvarDecl::None; 2255 2256 // Construct the decl. 2257 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, Loc, II, T, ac, 2258 (Expr *)BitfieldWidth); 2259 2260 // Process attributes attached to the ivar. 2261 ProcessDeclAttributes(NewID, D); 2262 2263 if (D.getInvalidType() || InvalidDecl) 2264 NewID->setInvalidDecl(); 2265 2266 return NewID; 2267} 2268 2269void Sema::ActOnFields(Scope* S, 2270 SourceLocation RecLoc, DeclTy *RecDecl, 2271 DeclTy **Fields, unsigned NumFields, 2272 SourceLocation LBrac, SourceLocation RBrac, 2273 AttributeList *Attr) { 2274 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 2275 assert(EnclosingDecl && "missing record or interface decl"); 2276 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 2277 2278 if (Record) 2279 if (RecordDecl* DefRecord = Record->getDefinition(Context)) { 2280 // Diagnose code like: 2281 // struct S { struct S {} X; }; 2282 // We discover this when we complete the outer S. Reject and ignore the 2283 // outer S. 2284 Diag(DefRecord->getLocation(), diag::err_nested_redefinition, 2285 DefRecord->getKindName()); 2286 Diag(RecLoc, diag::err_previous_definition); 2287 Record->setInvalidDecl(); 2288 return; 2289 } 2290 2291 // Verify that all the fields are okay. 2292 unsigned NumNamedMembers = 0; 2293 llvm::SmallVector<FieldDecl*, 32> RecFields; 2294 llvm::SmallSet<const IdentifierInfo*, 32> FieldIDs; 2295 2296 for (unsigned i = 0; i != NumFields; ++i) { 2297 2298 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 2299 assert(FD && "missing field decl"); 2300 2301 // Remember all fields. 2302 RecFields.push_back(FD); 2303 2304 // Get the type for the field. 2305 Type *FDTy = FD->getType().getTypePtr(); 2306 2307 // C99 6.7.2.1p2 - A field may not be a function type. 2308 if (FDTy->isFunctionType()) { 2309 Diag(FD->getLocation(), diag::err_field_declared_as_function, 2310 FD->getName()); 2311 FD->setInvalidDecl(); 2312 EnclosingDecl->setInvalidDecl(); 2313 continue; 2314 } 2315 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 2316 if (FDTy->isIncompleteType()) { 2317 if (!Record) { // Incomplete ivar type is always an error. 2318 Diag(FD->getLocation(), diag::err_field_incomplete, FD->getName()); 2319 FD->setInvalidDecl(); 2320 EnclosingDecl->setInvalidDecl(); 2321 continue; 2322 } 2323 if (i != NumFields-1 || // ... that the last member ... 2324 !Record->isStruct() || // ... of a structure ... 2325 !FDTy->isArrayType()) { //... may have incomplete array type. 2326 Diag(FD->getLocation(), diag::err_field_incomplete, FD->getName()); 2327 FD->setInvalidDecl(); 2328 EnclosingDecl->setInvalidDecl(); 2329 continue; 2330 } 2331 if (NumNamedMembers < 1) { //... must have more than named member ... 2332 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct, 2333 FD->getName()); 2334 FD->setInvalidDecl(); 2335 EnclosingDecl->setInvalidDecl(); 2336 continue; 2337 } 2338 // Okay, we have a legal flexible array member at the end of the struct. 2339 if (Record) 2340 Record->setHasFlexibleArrayMember(true); 2341 } 2342 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 2343 /// field of another structure or the element of an array. 2344 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 2345 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 2346 // If this is a member of a union, then entire union becomes "flexible". 2347 if (Record && Record->isUnion()) { 2348 Record->setHasFlexibleArrayMember(true); 2349 } else { 2350 // If this is a struct/class and this is not the last element, reject 2351 // it. Note that GCC supports variable sized arrays in the middle of 2352 // structures. 2353 if (i != NumFields-1) { 2354 Diag(FD->getLocation(), diag::err_variable_sized_type_in_struct, 2355 FD->getName()); 2356 FD->setInvalidDecl(); 2357 EnclosingDecl->setInvalidDecl(); 2358 continue; 2359 } 2360 // We support flexible arrays at the end of structs in other structs 2361 // as an extension. 2362 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct, 2363 FD->getName()); 2364 if (Record) 2365 Record->setHasFlexibleArrayMember(true); 2366 } 2367 } 2368 } 2369 /// A field cannot be an Objective-c object 2370 if (FDTy->isObjCInterfaceType()) { 2371 Diag(FD->getLocation(), diag::err_statically_allocated_object, 2372 FD->getName()); 2373 FD->setInvalidDecl(); 2374 EnclosingDecl->setInvalidDecl(); 2375 continue; 2376 } 2377 // Keep track of the number of named members. 2378 if (IdentifierInfo *II = FD->getIdentifier()) { 2379 // Detect duplicate member names. 2380 if (!FieldIDs.insert(II)) { 2381 Diag(FD->getLocation(), diag::err_duplicate_member, II->getName()); 2382 // Find the previous decl. 2383 SourceLocation PrevLoc; 2384 for (unsigned i = 0; ; ++i) { 2385 assert(i != RecFields.size() && "Didn't find previous def!"); 2386 if (RecFields[i]->getIdentifier() == II) { 2387 PrevLoc = RecFields[i]->getLocation(); 2388 break; 2389 } 2390 } 2391 Diag(PrevLoc, diag::err_previous_definition); 2392 FD->setInvalidDecl(); 2393 EnclosingDecl->setInvalidDecl(); 2394 continue; 2395 } 2396 ++NumNamedMembers; 2397 } 2398 } 2399 2400 // Okay, we successfully defined 'Record'. 2401 if (Record) { 2402 Record->defineBody(Context, &RecFields[0], RecFields.size()); 2403 // If this is a C++ record, HandleTagDeclDefinition will be invoked in 2404 // Sema::ActOnFinishCXXClassDef. 2405 if (!isa<CXXRecordDecl>(Record)) 2406 Consumer.HandleTagDeclDefinition(Record); 2407 } else { 2408 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 2409 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) 2410 ID->addInstanceVariablesToClass(ClsFields, RecFields.size(), RBrac); 2411 else if (ObjCImplementationDecl *IMPDecl = 2412 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 2413 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 2414 IMPDecl->ObjCAddInstanceVariablesToClassImpl(ClsFields, RecFields.size()); 2415 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 2416 } 2417 } 2418 2419 if (Attr) 2420 ProcessDeclAttributeList(Record, Attr); 2421} 2422 2423Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 2424 DeclTy *lastEnumConst, 2425 SourceLocation IdLoc, IdentifierInfo *Id, 2426 SourceLocation EqualLoc, ExprTy *val) { 2427 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 2428 EnumConstantDecl *LastEnumConst = 2429 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 2430 Expr *Val = static_cast<Expr*>(val); 2431 2432 // The scope passed in may not be a decl scope. Zip up the scope tree until 2433 // we find one that is. 2434 while ((S->getFlags() & Scope::DeclScope) == 0) 2435 S = S->getParent(); 2436 2437 // Verify that there isn't already something declared with this name in this 2438 // scope. 2439 if (Decl *PrevDecl = LookupDecl(Id, Decl::IDNS_Ordinary, S)) { 2440 // When in C++, we may get a TagDecl with the same name; in this case the 2441 // enum constant will 'hide' the tag. 2442 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 2443 "Received TagDecl when not in C++!"); 2444 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 2445 if (isa<EnumConstantDecl>(PrevDecl)) 2446 Diag(IdLoc, diag::err_redefinition_of_enumerator, Id->getName()); 2447 else 2448 Diag(IdLoc, diag::err_redefinition, Id->getName()); 2449 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 2450 delete Val; 2451 return 0; 2452 } 2453 } 2454 2455 llvm::APSInt EnumVal(32); 2456 QualType EltTy; 2457 if (Val) { 2458 // Make sure to promote the operand type to int. 2459 UsualUnaryConversions(Val); 2460 2461 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 2462 SourceLocation ExpLoc; 2463 if (!Val->isIntegerConstantExpr(EnumVal, Context, &ExpLoc)) { 2464 Diag(ExpLoc, diag::err_enum_value_not_integer_constant_expr, 2465 Id->getName()); 2466 delete Val; 2467 Val = 0; // Just forget about it. 2468 } else { 2469 EltTy = Val->getType(); 2470 } 2471 } 2472 2473 if (!Val) { 2474 if (LastEnumConst) { 2475 // Assign the last value + 1. 2476 EnumVal = LastEnumConst->getInitVal(); 2477 ++EnumVal; 2478 2479 // Check for overflow on increment. 2480 if (EnumVal < LastEnumConst->getInitVal()) 2481 Diag(IdLoc, diag::warn_enum_value_overflow); 2482 2483 EltTy = LastEnumConst->getType(); 2484 } else { 2485 // First value, set to zero. 2486 EltTy = Context.IntTy; 2487 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 2488 } 2489 } 2490 2491 EnumConstantDecl *New = 2492 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 2493 Val, EnumVal, 2494 LastEnumConst); 2495 2496 // Register this decl in the current scope stack. 2497 PushOnScopeChains(New, S); 2498 return New; 2499} 2500 2501// FIXME: For consistency with ActOnFields(), we should have the parser 2502// pass in the source location for the left/right braces. 2503void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 2504 DeclTy **Elements, unsigned NumElements) { 2505 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 2506 2507 if (Enum && Enum->isDefinition()) { 2508 // Diagnose code like: 2509 // enum e0 { 2510 // E0 = sizeof(enum e0 { E1 }) 2511 // }; 2512 Diag(Enum->getLocation(), diag::err_nested_redefinition, 2513 Enum->getName()); 2514 Diag(EnumLoc, diag::err_previous_definition); 2515 Enum->setInvalidDecl(); 2516 return; 2517 } 2518 // TODO: If the result value doesn't fit in an int, it must be a long or long 2519 // long value. ISO C does not support this, but GCC does as an extension, 2520 // emit a warning. 2521 unsigned IntWidth = Context.Target.getIntWidth(); 2522 2523 // Verify that all the values are okay, compute the size of the values, and 2524 // reverse the list. 2525 unsigned NumNegativeBits = 0; 2526 unsigned NumPositiveBits = 0; 2527 2528 // Keep track of whether all elements have type int. 2529 bool AllElementsInt = true; 2530 2531 EnumConstantDecl *EltList = 0; 2532 for (unsigned i = 0; i != NumElements; ++i) { 2533 EnumConstantDecl *ECD = 2534 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 2535 if (!ECD) continue; // Already issued a diagnostic. 2536 2537 // If the enum value doesn't fit in an int, emit an extension warning. 2538 const llvm::APSInt &InitVal = ECD->getInitVal(); 2539 assert(InitVal.getBitWidth() >= IntWidth && 2540 "Should have promoted value to int"); 2541 if (InitVal.getBitWidth() > IntWidth) { 2542 llvm::APSInt V(InitVal); 2543 V.trunc(IntWidth); 2544 V.extend(InitVal.getBitWidth()); 2545 if (V != InitVal) 2546 Diag(ECD->getLocation(), diag::ext_enum_value_not_int, 2547 InitVal.toString(10)); 2548 } 2549 2550 // Keep track of the size of positive and negative values. 2551 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 2552 NumPositiveBits = std::max(NumPositiveBits, 2553 (unsigned)InitVal.getActiveBits()); 2554 else 2555 NumNegativeBits = std::max(NumNegativeBits, 2556 (unsigned)InitVal.getMinSignedBits()); 2557 2558 // Keep track of whether every enum element has type int (very commmon). 2559 if (AllElementsInt) 2560 AllElementsInt = ECD->getType() == Context.IntTy; 2561 2562 ECD->setNextDeclarator(EltList); 2563 EltList = ECD; 2564 } 2565 2566 // Figure out the type that should be used for this enum. 2567 // FIXME: Support attribute(packed) on enums and -fshort-enums. 2568 QualType BestType; 2569 unsigned BestWidth; 2570 2571 if (NumNegativeBits) { 2572 // If there is a negative value, figure out the smallest integer type (of 2573 // int/long/longlong) that fits. 2574 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 2575 BestType = Context.IntTy; 2576 BestWidth = IntWidth; 2577 } else { 2578 BestWidth = Context.Target.getLongWidth(); 2579 2580 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 2581 BestType = Context.LongTy; 2582 else { 2583 BestWidth = Context.Target.getLongLongWidth(); 2584 2585 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 2586 Diag(Enum->getLocation(), diag::warn_enum_too_large); 2587 BestType = Context.LongLongTy; 2588 } 2589 } 2590 } else { 2591 // If there is no negative value, figure out which of uint, ulong, ulonglong 2592 // fits. 2593 if (NumPositiveBits <= IntWidth) { 2594 BestType = Context.UnsignedIntTy; 2595 BestWidth = IntWidth; 2596 } else if (NumPositiveBits <= 2597 (BestWidth = Context.Target.getLongWidth())) { 2598 BestType = Context.UnsignedLongTy; 2599 } else { 2600 BestWidth = Context.Target.getLongLongWidth(); 2601 assert(NumPositiveBits <= BestWidth && 2602 "How could an initializer get larger than ULL?"); 2603 BestType = Context.UnsignedLongLongTy; 2604 } 2605 } 2606 2607 // Loop over all of the enumerator constants, changing their types to match 2608 // the type of the enum if needed. 2609 for (unsigned i = 0; i != NumElements; ++i) { 2610 EnumConstantDecl *ECD = 2611 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 2612 if (!ECD) continue; // Already issued a diagnostic. 2613 2614 // Standard C says the enumerators have int type, but we allow, as an 2615 // extension, the enumerators to be larger than int size. If each 2616 // enumerator value fits in an int, type it as an int, otherwise type it the 2617 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 2618 // that X has type 'int', not 'unsigned'. 2619 if (ECD->getType() == Context.IntTy) { 2620 // Make sure the init value is signed. 2621 llvm::APSInt IV = ECD->getInitVal(); 2622 IV.setIsSigned(true); 2623 ECD->setInitVal(IV); 2624 continue; // Already int type. 2625 } 2626 2627 // Determine whether the value fits into an int. 2628 llvm::APSInt InitVal = ECD->getInitVal(); 2629 bool FitsInInt; 2630 if (InitVal.isUnsigned() || !InitVal.isNegative()) 2631 FitsInInt = InitVal.getActiveBits() < IntWidth; 2632 else 2633 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 2634 2635 // If it fits into an integer type, force it. Otherwise force it to match 2636 // the enum decl type. 2637 QualType NewTy; 2638 unsigned NewWidth; 2639 bool NewSign; 2640 if (FitsInInt) { 2641 NewTy = Context.IntTy; 2642 NewWidth = IntWidth; 2643 NewSign = true; 2644 } else if (ECD->getType() == BestType) { 2645 // Already the right type! 2646 continue; 2647 } else { 2648 NewTy = BestType; 2649 NewWidth = BestWidth; 2650 NewSign = BestType->isSignedIntegerType(); 2651 } 2652 2653 // Adjust the APSInt value. 2654 InitVal.extOrTrunc(NewWidth); 2655 InitVal.setIsSigned(NewSign); 2656 ECD->setInitVal(InitVal); 2657 2658 // Adjust the Expr initializer and type. 2659 ECD->setInitExpr(new ImplicitCastExpr(NewTy, ECD->getInitExpr())); 2660 ECD->setType(NewTy); 2661 } 2662 2663 Enum->defineElements(EltList, BestType); 2664 Consumer.HandleTagDeclDefinition(Enum); 2665} 2666 2667Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 2668 ExprTy *expr) { 2669 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr); 2670 2671 return FileScopeAsmDecl::Create(Context, Loc, AsmString); 2672} 2673 2674Sema::DeclTy* Sema::ActOnLinkageSpec(SourceLocation Loc, 2675 SourceLocation LBrace, 2676 SourceLocation RBrace, 2677 const char *Lang, 2678 unsigned StrSize, 2679 DeclTy *D) { 2680 LinkageSpecDecl::LanguageIDs Language; 2681 Decl *dcl = static_cast<Decl *>(D); 2682 if (strncmp(Lang, "\"C\"", StrSize) == 0) 2683 Language = LinkageSpecDecl::lang_c; 2684 else if (strncmp(Lang, "\"C++\"", StrSize) == 0) 2685 Language = LinkageSpecDecl::lang_cxx; 2686 else { 2687 Diag(Loc, diag::err_bad_language); 2688 return 0; 2689 } 2690 2691 // FIXME: Add all the various semantics of linkage specifications 2692 return LinkageSpecDecl::Create(Context, Loc, Language, dcl); 2693} 2694 2695void Sema::ActOnPragmaPack(PragmaPackKind Kind, IdentifierInfo *Name, 2696 ExprTy *alignment, SourceLocation PragmaLoc, 2697 SourceLocation LParenLoc, SourceLocation RParenLoc) { 2698 Expr *Alignment = static_cast<Expr *>(alignment); 2699 2700 // If specified then alignment must be a "small" power of two. 2701 unsigned AlignmentVal = 0; 2702 if (Alignment) { 2703 llvm::APSInt Val; 2704 if (!Alignment->isIntegerConstantExpr(Val, Context) || 2705 !Val.isPowerOf2() || 2706 Val.getZExtValue() > 16) { 2707 Diag(PragmaLoc, diag::warn_pragma_pack_invalid_alignment); 2708 delete Alignment; 2709 return; // Ignore 2710 } 2711 2712 AlignmentVal = (unsigned) Val.getZExtValue(); 2713 } 2714 2715 switch (Kind) { 2716 case Action::PPK_Default: // pack([n]) 2717 PackContext.setAlignment(AlignmentVal); 2718 break; 2719 2720 case Action::PPK_Show: // pack(show) 2721 // Show the current alignment, making sure to show the right value 2722 // for the default. 2723 AlignmentVal = PackContext.getAlignment(); 2724 // FIXME: This should come from the target. 2725 if (AlignmentVal == 0) 2726 AlignmentVal = 8; 2727 Diag(PragmaLoc, diag::warn_pragma_pack_show, llvm::utostr(AlignmentVal)); 2728 break; 2729 2730 case Action::PPK_Push: // pack(push [, id] [, [n]) 2731 PackContext.push(Name); 2732 // Set the new alignment if specified. 2733 if (Alignment) 2734 PackContext.setAlignment(AlignmentVal); 2735 break; 2736 2737 case Action::PPK_Pop: // pack(pop [, id] [, n]) 2738 // MSDN, C/C++ Preprocessor Reference > Pragma Directives > pack: 2739 // "#pragma pack(pop, identifier, n) is undefined" 2740 if (Alignment && Name) 2741 Diag(PragmaLoc, diag::warn_pragma_pack_pop_identifer_and_alignment); 2742 2743 // Do the pop. 2744 if (!PackContext.pop(Name)) { 2745 // If a name was specified then failure indicates the name 2746 // wasn't found. Otherwise failure indicates the stack was 2747 // empty. 2748 Diag(PragmaLoc, diag::warn_pragma_pack_pop_failed, 2749 Name ? "no record matching name" : "stack empty"); 2750 2751 // FIXME: Warn about popping named records as MSVC does. 2752 } else { 2753 // Pop succeeded, set the new alignment if specified. 2754 if (Alignment) 2755 PackContext.setAlignment(AlignmentVal); 2756 } 2757 break; 2758 2759 default: 2760 assert(0 && "Invalid #pragma pack kind."); 2761 } 2762} 2763 2764bool PragmaPackStack::pop(IdentifierInfo *Name) { 2765 if (Stack.empty()) 2766 return false; 2767 2768 // If name is empty just pop top. 2769 if (!Name) { 2770 Alignment = Stack.back().first; 2771 Stack.pop_back(); 2772 return true; 2773 } 2774 2775 // Otherwise, find the named record. 2776 for (unsigned i = Stack.size(); i != 0; ) { 2777 --i; 2778 if (strcmp(Stack[i].second.c_str(), Name->getName()) == 0) { 2779 // Found it, pop up to and including this record. 2780 Alignment = Stack[i].first; 2781 Stack.erase(Stack.begin() + i, Stack.end()); 2782 return true; 2783 } 2784 } 2785 2786 return false; 2787} 2788