SemaChecking.cpp revision 2d88708cbe4e4ec5e04e4acb6bd7f5be68557379
1//===--- SemaChecking.cpp - Extra Semantic Checking -----------------------===// 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 extra semantic analysis beyond what is enforced 11// by the C type system. 12// 13//===----------------------------------------------------------------------===// 14 15#include "clang/Sema/Sema.h" 16#include "clang/Sema/SemaInternal.h" 17#include "clang/Sema/ScopeInfo.h" 18#include "clang/Analysis/Analyses/FormatString.h" 19#include "clang/AST/ASTContext.h" 20#include "clang/AST/CharUnits.h" 21#include "clang/AST/DeclCXX.h" 22#include "clang/AST/DeclObjC.h" 23#include "clang/AST/ExprCXX.h" 24#include "clang/AST/ExprObjC.h" 25#include "clang/AST/DeclObjC.h" 26#include "clang/AST/StmtCXX.h" 27#include "clang/AST/StmtObjC.h" 28#include "clang/Lex/LiteralSupport.h" 29#include "clang/Lex/Preprocessor.h" 30#include "llvm/ADT/BitVector.h" 31#include "llvm/ADT/STLExtras.h" 32#include "llvm/Support/raw_ostream.h" 33#include "clang/Basic/TargetBuiltins.h" 34#include "clang/Basic/TargetInfo.h" 35#include <limits> 36using namespace clang; 37using namespace sema; 38 39/// getLocationOfStringLiteralByte - Return a source location that points to the 40/// specified byte of the specified string literal. 41/// 42/// Strings are amazingly complex. They can be formed from multiple tokens and 43/// can have escape sequences in them in addition to the usual trigraph and 44/// escaped newline business. This routine handles this complexity. 45/// 46SourceLocation Sema::getLocationOfStringLiteralByte(const StringLiteral *SL, 47 unsigned ByteNo) const { 48 assert(!SL->isWide() && "This doesn't work for wide strings yet"); 49 50 // Loop over all of the tokens in this string until we find the one that 51 // contains the byte we're looking for. 52 unsigned TokNo = 0; 53 while (1) { 54 assert(TokNo < SL->getNumConcatenated() && "Invalid byte number!"); 55 SourceLocation StrTokLoc = SL->getStrTokenLoc(TokNo); 56 57 // Get the spelling of the string so that we can get the data that makes up 58 // the string literal, not the identifier for the macro it is potentially 59 // expanded through. 60 SourceLocation StrTokSpellingLoc = SourceMgr.getSpellingLoc(StrTokLoc); 61 62 // Re-lex the token to get its length and original spelling. 63 std::pair<FileID, unsigned> LocInfo = 64 SourceMgr.getDecomposedLoc(StrTokSpellingLoc); 65 bool Invalid = false; 66 llvm::StringRef Buffer = SourceMgr.getBufferData(LocInfo.first, &Invalid); 67 if (Invalid) 68 return StrTokSpellingLoc; 69 70 const char *StrData = Buffer.data()+LocInfo.second; 71 72 // Create a langops struct and enable trigraphs. This is sufficient for 73 // relexing tokens. 74 LangOptions LangOpts; 75 LangOpts.Trigraphs = true; 76 77 // Create a lexer starting at the beginning of this token. 78 Lexer TheLexer(StrTokSpellingLoc, LangOpts, Buffer.begin(), StrData, 79 Buffer.end()); 80 Token TheTok; 81 TheLexer.LexFromRawLexer(TheTok); 82 83 // Use the StringLiteralParser to compute the length of the string in bytes. 84 StringLiteralParser SLP(&TheTok, 1, PP, /*Complain=*/false); 85 unsigned TokNumBytes = SLP.GetStringLength(); 86 87 // If the byte is in this token, return the location of the byte. 88 if (ByteNo < TokNumBytes || 89 (ByteNo == TokNumBytes && TokNo == SL->getNumConcatenated())) { 90 unsigned Offset = 91 StringLiteralParser::getOffsetOfStringByte(TheTok, ByteNo, PP, 92 /*Complain=*/false); 93 94 // Now that we know the offset of the token in the spelling, use the 95 // preprocessor to get the offset in the original source. 96 return PP.AdvanceToTokenCharacter(StrTokLoc, Offset); 97 } 98 99 // Move to the next string token. 100 ++TokNo; 101 ByteNo -= TokNumBytes; 102 } 103} 104 105/// CheckablePrintfAttr - does a function call have a "printf" attribute 106/// and arguments that merit checking? 107bool Sema::CheckablePrintfAttr(const FormatAttr *Format, CallExpr *TheCall) { 108 if (Format->getType() == "printf") return true; 109 if (Format->getType() == "printf0") { 110 // printf0 allows null "format" string; if so don't check format/args 111 unsigned format_idx = Format->getFormatIdx() - 1; 112 // Does the index refer to the implicit object argument? 113 if (isa<CXXMemberCallExpr>(TheCall)) { 114 if (format_idx == 0) 115 return false; 116 --format_idx; 117 } 118 if (format_idx < TheCall->getNumArgs()) { 119 Expr *Format = TheCall->getArg(format_idx)->IgnoreParenCasts(); 120 if (!Format->isNullPointerConstant(Context, 121 Expr::NPC_ValueDependentIsNull)) 122 return true; 123 } 124 } 125 return false; 126} 127 128ExprResult 129Sema::CheckBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall) { 130 ExprResult TheCallResult(Owned(TheCall)); 131 132 switch (BuiltinID) { 133 case Builtin::BI__builtin___CFStringMakeConstantString: 134 assert(TheCall->getNumArgs() == 1 && 135 "Wrong # arguments to builtin CFStringMakeConstantString"); 136 if (CheckObjCString(TheCall->getArg(0))) 137 return ExprError(); 138 break; 139 case Builtin::BI__builtin_stdarg_start: 140 case Builtin::BI__builtin_va_start: 141 if (SemaBuiltinVAStart(TheCall)) 142 return ExprError(); 143 break; 144 case Builtin::BI__builtin_isgreater: 145 case Builtin::BI__builtin_isgreaterequal: 146 case Builtin::BI__builtin_isless: 147 case Builtin::BI__builtin_islessequal: 148 case Builtin::BI__builtin_islessgreater: 149 case Builtin::BI__builtin_isunordered: 150 if (SemaBuiltinUnorderedCompare(TheCall)) 151 return ExprError(); 152 break; 153 case Builtin::BI__builtin_fpclassify: 154 if (SemaBuiltinFPClassification(TheCall, 6)) 155 return ExprError(); 156 break; 157 case Builtin::BI__builtin_isfinite: 158 case Builtin::BI__builtin_isinf: 159 case Builtin::BI__builtin_isinf_sign: 160 case Builtin::BI__builtin_isnan: 161 case Builtin::BI__builtin_isnormal: 162 if (SemaBuiltinFPClassification(TheCall, 1)) 163 return ExprError(); 164 break; 165 case Builtin::BI__builtin_return_address: 166 case Builtin::BI__builtin_frame_address: { 167 llvm::APSInt Result; 168 if (SemaBuiltinConstantArg(TheCall, 0, Result)) 169 return ExprError(); 170 break; 171 } 172 case Builtin::BI__builtin_eh_return_data_regno: { 173 llvm::APSInt Result; 174 if (SemaBuiltinConstantArg(TheCall, 0, Result)) 175 return ExprError(); 176 break; 177 } 178 case Builtin::BI__builtin_shufflevector: 179 return SemaBuiltinShuffleVector(TheCall); 180 // TheCall will be freed by the smart pointer here, but that's fine, since 181 // SemaBuiltinShuffleVector guts it, but then doesn't release it. 182 case Builtin::BI__builtin_prefetch: 183 if (SemaBuiltinPrefetch(TheCall)) 184 return ExprError(); 185 break; 186 case Builtin::BI__builtin_object_size: 187 if (SemaBuiltinObjectSize(TheCall)) 188 return ExprError(); 189 break; 190 case Builtin::BI__builtin_longjmp: 191 if (SemaBuiltinLongjmp(TheCall)) 192 return ExprError(); 193 break; 194 case Builtin::BI__sync_fetch_and_add: 195 case Builtin::BI__sync_fetch_and_sub: 196 case Builtin::BI__sync_fetch_and_or: 197 case Builtin::BI__sync_fetch_and_and: 198 case Builtin::BI__sync_fetch_and_xor: 199 case Builtin::BI__sync_add_and_fetch: 200 case Builtin::BI__sync_sub_and_fetch: 201 case Builtin::BI__sync_and_and_fetch: 202 case Builtin::BI__sync_or_and_fetch: 203 case Builtin::BI__sync_xor_and_fetch: 204 case Builtin::BI__sync_val_compare_and_swap: 205 case Builtin::BI__sync_bool_compare_and_swap: 206 case Builtin::BI__sync_lock_test_and_set: 207 case Builtin::BI__sync_lock_release: 208 return SemaBuiltinAtomicOverloaded(move(TheCallResult)); 209 } 210 211 // Since the target specific builtins for each arch overlap, only check those 212 // of the arch we are compiling for. 213 if (BuiltinID >= Builtin::FirstTSBuiltin) { 214 switch (Context.Target.getTriple().getArch()) { 215 case llvm::Triple::arm: 216 case llvm::Triple::thumb: 217 if (CheckARMBuiltinFunctionCall(BuiltinID, TheCall)) 218 return ExprError(); 219 break; 220 case llvm::Triple::x86: 221 case llvm::Triple::x86_64: 222 if (CheckX86BuiltinFunctionCall(BuiltinID, TheCall)) 223 return ExprError(); 224 break; 225 default: 226 break; 227 } 228 } 229 230 return move(TheCallResult); 231} 232 233bool Sema::CheckX86BuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall) { 234 switch (BuiltinID) { 235 case X86::BI__builtin_ia32_palignr128: 236 case X86::BI__builtin_ia32_palignr: { 237 llvm::APSInt Result; 238 if (SemaBuiltinConstantArg(TheCall, 2, Result)) 239 return true; 240 break; 241 } 242 } 243 return false; 244} 245 246// Get the valid immediate range for the specified NEON type code. 247static unsigned RFT(unsigned t, bool shift = false) { 248 bool quad = t & 0x10; 249 250 switch (t & 0x7) { 251 case 0: // i8 252 return shift ? 7 : (8 << (int)quad) - 1; 253 case 1: // i16 254 return shift ? 15 : (4 << (int)quad) - 1; 255 case 2: // i32 256 return shift ? 31 : (2 << (int)quad) - 1; 257 case 3: // i64 258 return shift ? 63 : (1 << (int)quad) - 1; 259 case 4: // f32 260 assert(!shift && "cannot shift float types!"); 261 return (2 << (int)quad) - 1; 262 case 5: // poly8 263 assert(!shift && "cannot shift polynomial types!"); 264 return (8 << (int)quad) - 1; 265 case 6: // poly16 266 assert(!shift && "cannot shift polynomial types!"); 267 return (4 << (int)quad) - 1; 268 case 7: // float16 269 assert(!shift && "cannot shift float types!"); 270 return (4 << (int)quad) - 1; 271 } 272 return 0; 273} 274 275bool Sema::CheckARMBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall) { 276 llvm::APSInt Result; 277 278 unsigned mask = 0; 279 unsigned TV = 0; 280 switch (BuiltinID) { 281#define GET_NEON_OVERLOAD_CHECK 282#include "clang/Basic/arm_neon.inc" 283#undef GET_NEON_OVERLOAD_CHECK 284 } 285 286 // For NEON intrinsics which are overloaded on vector element type, validate 287 // the immediate which specifies which variant to emit. 288 if (mask) { 289 unsigned ArgNo = TheCall->getNumArgs()-1; 290 if (SemaBuiltinConstantArg(TheCall, ArgNo, Result)) 291 return true; 292 293 TV = Result.getLimitedValue(32); 294 if ((TV > 31) || (mask & (1 << TV)) == 0) 295 return Diag(TheCall->getLocStart(), diag::err_invalid_neon_type_code) 296 << TheCall->getArg(ArgNo)->getSourceRange(); 297 } 298 299 // For NEON intrinsics which take an immediate value as part of the 300 // instruction, range check them here. 301 unsigned i = 0, l = 0, u = 0; 302 switch (BuiltinID) { 303 default: return false; 304 case ARM::BI__builtin_arm_ssat: i = 1; l = 1; u = 31; break; 305 case ARM::BI__builtin_arm_usat: i = 1; u = 31; break; 306 case ARM::BI__builtin_arm_vcvtr_f: 307 case ARM::BI__builtin_arm_vcvtr_d: i = 1; u = 1; break; 308#define GET_NEON_IMMEDIATE_CHECK 309#include "clang/Basic/arm_neon.inc" 310#undef GET_NEON_IMMEDIATE_CHECK 311 }; 312 313 // Check that the immediate argument is actually a constant. 314 if (SemaBuiltinConstantArg(TheCall, i, Result)) 315 return true; 316 317 // Range check against the upper/lower values for this isntruction. 318 unsigned Val = Result.getZExtValue(); 319 if (Val < l || Val > (u + l)) 320 return Diag(TheCall->getLocStart(), diag::err_argument_invalid_range) 321 << l << u+l << TheCall->getArg(i)->getSourceRange(); 322 323 // FIXME: VFP Intrinsics should error if VFP not present. 324 return false; 325} 326 327/// CheckFunctionCall - Check a direct function call for various correctness 328/// and safety properties not strictly enforced by the C type system. 329bool Sema::CheckFunctionCall(FunctionDecl *FDecl, CallExpr *TheCall) { 330 // Get the IdentifierInfo* for the called function. 331 IdentifierInfo *FnInfo = FDecl->getIdentifier(); 332 333 // None of the checks below are needed for functions that don't have 334 // simple names (e.g., C++ conversion functions). 335 if (!FnInfo) 336 return false; 337 338 // FIXME: This mechanism should be abstracted to be less fragile and 339 // more efficient. For example, just map function ids to custom 340 // handlers. 341 342 // Printf checking. 343 if (const FormatAttr *Format = FDecl->getAttr<FormatAttr>()) { 344 const bool b = Format->getType() == "scanf"; 345 if (b || CheckablePrintfAttr(Format, TheCall)) { 346 bool HasVAListArg = Format->getFirstArg() == 0; 347 CheckPrintfScanfArguments(TheCall, HasVAListArg, 348 Format->getFormatIdx() - 1, 349 HasVAListArg ? 0 : Format->getFirstArg() - 1, 350 !b); 351 } 352 } 353 354 specific_attr_iterator<NonNullAttr> 355 i = FDecl->specific_attr_begin<NonNullAttr>(), 356 e = FDecl->specific_attr_end<NonNullAttr>(); 357 358 for (; i != e; ++i) 359 CheckNonNullArguments(*i, TheCall); 360 361 return false; 362} 363 364bool Sema::CheckBlockCall(NamedDecl *NDecl, CallExpr *TheCall) { 365 // Printf checking. 366 const FormatAttr *Format = NDecl->getAttr<FormatAttr>(); 367 if (!Format) 368 return false; 369 370 const VarDecl *V = dyn_cast<VarDecl>(NDecl); 371 if (!V) 372 return false; 373 374 QualType Ty = V->getType(); 375 if (!Ty->isBlockPointerType()) 376 return false; 377 378 const bool b = Format->getType() == "scanf"; 379 if (!b && !CheckablePrintfAttr(Format, TheCall)) 380 return false; 381 382 bool HasVAListArg = Format->getFirstArg() == 0; 383 CheckPrintfScanfArguments(TheCall, HasVAListArg, Format->getFormatIdx() - 1, 384 HasVAListArg ? 0 : Format->getFirstArg() - 1, !b); 385 386 return false; 387} 388 389/// SemaBuiltinAtomicOverloaded - We have a call to a function like 390/// __sync_fetch_and_add, which is an overloaded function based on the pointer 391/// type of its first argument. The main ActOnCallExpr routines have already 392/// promoted the types of arguments because all of these calls are prototyped as 393/// void(...). 394/// 395/// This function goes through and does final semantic checking for these 396/// builtins, 397ExprResult 398Sema::SemaBuiltinAtomicOverloaded(ExprResult TheCallResult) { 399 CallExpr *TheCall = (CallExpr *)TheCallResult.get(); 400 DeclRefExpr *DRE =cast<DeclRefExpr>(TheCall->getCallee()->IgnoreParenCasts()); 401 FunctionDecl *FDecl = cast<FunctionDecl>(DRE->getDecl()); 402 403 // Ensure that we have at least one argument to do type inference from. 404 if (TheCall->getNumArgs() < 1) { 405 Diag(TheCall->getLocEnd(), diag::err_typecheck_call_too_few_args_at_least) 406 << 0 << 1 << TheCall->getNumArgs() 407 << TheCall->getCallee()->getSourceRange(); 408 return ExprError(); 409 } 410 411 // Inspect the first argument of the atomic builtin. This should always be 412 // a pointer type, whose element is an integral scalar or pointer type. 413 // Because it is a pointer type, we don't have to worry about any implicit 414 // casts here. 415 // FIXME: We don't allow floating point scalars as input. 416 Expr *FirstArg = TheCall->getArg(0); 417 if (!FirstArg->getType()->isPointerType()) { 418 Diag(DRE->getLocStart(), diag::err_atomic_builtin_must_be_pointer) 419 << FirstArg->getType() << FirstArg->getSourceRange(); 420 return ExprError(); 421 } 422 423 QualType ValType = 424 FirstArg->getType()->getAs<PointerType>()->getPointeeType(); 425 if (!ValType->isIntegerType() && !ValType->isPointerType() && 426 !ValType->isBlockPointerType()) { 427 Diag(DRE->getLocStart(), diag::err_atomic_builtin_must_be_pointer_intptr) 428 << FirstArg->getType() << FirstArg->getSourceRange(); 429 return ExprError(); 430 } 431 432 // The majority of builtins return a value, but a few have special return 433 // types, so allow them to override appropriately below. 434 QualType ResultType = ValType; 435 436 // We need to figure out which concrete builtin this maps onto. For example, 437 // __sync_fetch_and_add with a 2 byte object turns into 438 // __sync_fetch_and_add_2. 439#define BUILTIN_ROW(x) \ 440 { Builtin::BI##x##_1, Builtin::BI##x##_2, Builtin::BI##x##_4, \ 441 Builtin::BI##x##_8, Builtin::BI##x##_16 } 442 443 static const unsigned BuiltinIndices[][5] = { 444 BUILTIN_ROW(__sync_fetch_and_add), 445 BUILTIN_ROW(__sync_fetch_and_sub), 446 BUILTIN_ROW(__sync_fetch_and_or), 447 BUILTIN_ROW(__sync_fetch_and_and), 448 BUILTIN_ROW(__sync_fetch_and_xor), 449 450 BUILTIN_ROW(__sync_add_and_fetch), 451 BUILTIN_ROW(__sync_sub_and_fetch), 452 BUILTIN_ROW(__sync_and_and_fetch), 453 BUILTIN_ROW(__sync_or_and_fetch), 454 BUILTIN_ROW(__sync_xor_and_fetch), 455 456 BUILTIN_ROW(__sync_val_compare_and_swap), 457 BUILTIN_ROW(__sync_bool_compare_and_swap), 458 BUILTIN_ROW(__sync_lock_test_and_set), 459 BUILTIN_ROW(__sync_lock_release) 460 }; 461#undef BUILTIN_ROW 462 463 // Determine the index of the size. 464 unsigned SizeIndex; 465 switch (Context.getTypeSizeInChars(ValType).getQuantity()) { 466 case 1: SizeIndex = 0; break; 467 case 2: SizeIndex = 1; break; 468 case 4: SizeIndex = 2; break; 469 case 8: SizeIndex = 3; break; 470 case 16: SizeIndex = 4; break; 471 default: 472 Diag(DRE->getLocStart(), diag::err_atomic_builtin_pointer_size) 473 << FirstArg->getType() << FirstArg->getSourceRange(); 474 return ExprError(); 475 } 476 477 // Each of these builtins has one pointer argument, followed by some number of 478 // values (0, 1 or 2) followed by a potentially empty varags list of stuff 479 // that we ignore. Find out which row of BuiltinIndices to read from as well 480 // as the number of fixed args. 481 unsigned BuiltinID = FDecl->getBuiltinID(); 482 unsigned BuiltinIndex, NumFixed = 1; 483 switch (BuiltinID) { 484 default: assert(0 && "Unknown overloaded atomic builtin!"); 485 case Builtin::BI__sync_fetch_and_add: BuiltinIndex = 0; break; 486 case Builtin::BI__sync_fetch_and_sub: BuiltinIndex = 1; break; 487 case Builtin::BI__sync_fetch_and_or: BuiltinIndex = 2; break; 488 case Builtin::BI__sync_fetch_and_and: BuiltinIndex = 3; break; 489 case Builtin::BI__sync_fetch_and_xor: BuiltinIndex = 4; break; 490 491 case Builtin::BI__sync_add_and_fetch: BuiltinIndex = 5; break; 492 case Builtin::BI__sync_sub_and_fetch: BuiltinIndex = 6; break; 493 case Builtin::BI__sync_and_and_fetch: BuiltinIndex = 7; break; 494 case Builtin::BI__sync_or_and_fetch: BuiltinIndex = 8; break; 495 case Builtin::BI__sync_xor_and_fetch: BuiltinIndex = 9; break; 496 497 case Builtin::BI__sync_val_compare_and_swap: 498 BuiltinIndex = 10; 499 NumFixed = 2; 500 break; 501 case Builtin::BI__sync_bool_compare_and_swap: 502 BuiltinIndex = 11; 503 NumFixed = 2; 504 ResultType = Context.BoolTy; 505 break; 506 case Builtin::BI__sync_lock_test_and_set: BuiltinIndex = 12; break; 507 case Builtin::BI__sync_lock_release: 508 BuiltinIndex = 13; 509 NumFixed = 0; 510 ResultType = Context.VoidTy; 511 break; 512 } 513 514 // Now that we know how many fixed arguments we expect, first check that we 515 // have at least that many. 516 if (TheCall->getNumArgs() < 1+NumFixed) { 517 Diag(TheCall->getLocEnd(), diag::err_typecheck_call_too_few_args_at_least) 518 << 0 << 1+NumFixed << TheCall->getNumArgs() 519 << TheCall->getCallee()->getSourceRange(); 520 return ExprError(); 521 } 522 523 // Get the decl for the concrete builtin from this, we can tell what the 524 // concrete integer type we should convert to is. 525 unsigned NewBuiltinID = BuiltinIndices[BuiltinIndex][SizeIndex]; 526 const char *NewBuiltinName = Context.BuiltinInfo.GetName(NewBuiltinID); 527 IdentifierInfo *NewBuiltinII = PP.getIdentifierInfo(NewBuiltinName); 528 FunctionDecl *NewBuiltinDecl = 529 cast<FunctionDecl>(LazilyCreateBuiltin(NewBuiltinII, NewBuiltinID, 530 TUScope, false, DRE->getLocStart())); 531 532 // The first argument --- the pointer --- has a fixed type; we 533 // deduce the types of the rest of the arguments accordingly. Walk 534 // the remaining arguments, converting them to the deduced value type. 535 for (unsigned i = 0; i != NumFixed; ++i) { 536 Expr *Arg = TheCall->getArg(i+1); 537 538 // If the argument is an implicit cast, then there was a promotion due to 539 // "...", just remove it now. 540 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(Arg)) { 541 Arg = ICE->getSubExpr(); 542 ICE->setSubExpr(0); 543 TheCall->setArg(i+1, Arg); 544 } 545 546 // GCC does an implicit conversion to the pointer or integer ValType. This 547 // can fail in some cases (1i -> int**), check for this error case now. 548 CastKind Kind = CK_Unknown; 549 CXXCastPath BasePath; 550 if (CheckCastTypes(Arg->getSourceRange(), ValType, Arg, Kind, BasePath)) 551 return ExprError(); 552 553 // Okay, we have something that *can* be converted to the right type. Check 554 // to see if there is a potentially weird extension going on here. This can 555 // happen when you do an atomic operation on something like an char* and 556 // pass in 42. The 42 gets converted to char. This is even more strange 557 // for things like 45.123 -> char, etc. 558 // FIXME: Do this check. 559 ImpCastExprToType(Arg, ValType, Kind, VK_RValue, &BasePath); 560 TheCall->setArg(i+1, Arg); 561 } 562 563 // Switch the DeclRefExpr to refer to the new decl. 564 DRE->setDecl(NewBuiltinDecl); 565 DRE->setType(NewBuiltinDecl->getType()); 566 567 // Set the callee in the CallExpr. 568 // FIXME: This leaks the original parens and implicit casts. 569 Expr *PromotedCall = DRE; 570 UsualUnaryConversions(PromotedCall); 571 TheCall->setCallee(PromotedCall); 572 573 // Change the result type of the call to match the original value type. This 574 // is arbitrary, but the codegen for these builtins ins design to handle it 575 // gracefully. 576 TheCall->setType(ResultType); 577 578 return move(TheCallResult); 579} 580 581 582/// CheckObjCString - Checks that the argument to the builtin 583/// CFString constructor is correct 584/// FIXME: GCC currently emits the following warning: 585/// "warning: input conversion stopped due to an input byte that does not 586/// belong to the input codeset UTF-8" 587/// Note: It might also make sense to do the UTF-16 conversion here (would 588/// simplify the backend). 589bool Sema::CheckObjCString(Expr *Arg) { 590 Arg = Arg->IgnoreParenCasts(); 591 StringLiteral *Literal = dyn_cast<StringLiteral>(Arg); 592 593 if (!Literal || Literal->isWide()) { 594 Diag(Arg->getLocStart(), diag::err_cfstring_literal_not_string_constant) 595 << Arg->getSourceRange(); 596 return true; 597 } 598 599 size_t NulPos = Literal->getString().find('\0'); 600 if (NulPos != llvm::StringRef::npos) { 601 Diag(getLocationOfStringLiteralByte(Literal, NulPos), 602 diag::warn_cfstring_literal_contains_nul_character) 603 << Arg->getSourceRange(); 604 } 605 606 return false; 607} 608 609/// SemaBuiltinVAStart - Check the arguments to __builtin_va_start for validity. 610/// Emit an error and return true on failure, return false on success. 611bool Sema::SemaBuiltinVAStart(CallExpr *TheCall) { 612 Expr *Fn = TheCall->getCallee(); 613 if (TheCall->getNumArgs() > 2) { 614 Diag(TheCall->getArg(2)->getLocStart(), 615 diag::err_typecheck_call_too_many_args) 616 << 0 /*function call*/ << 2 << TheCall->getNumArgs() 617 << Fn->getSourceRange() 618 << SourceRange(TheCall->getArg(2)->getLocStart(), 619 (*(TheCall->arg_end()-1))->getLocEnd()); 620 return true; 621 } 622 623 if (TheCall->getNumArgs() < 2) { 624 return Diag(TheCall->getLocEnd(), 625 diag::err_typecheck_call_too_few_args_at_least) 626 << 0 /*function call*/ << 2 << TheCall->getNumArgs(); 627 } 628 629 // Determine whether the current function is variadic or not. 630 BlockScopeInfo *CurBlock = getCurBlock(); 631 bool isVariadic; 632 if (CurBlock) 633 isVariadic = CurBlock->TheDecl->isVariadic(); 634 else if (FunctionDecl *FD = getCurFunctionDecl()) 635 isVariadic = FD->isVariadic(); 636 else 637 isVariadic = getCurMethodDecl()->isVariadic(); 638 639 if (!isVariadic) { 640 Diag(Fn->getLocStart(), diag::err_va_start_used_in_non_variadic_function); 641 return true; 642 } 643 644 // Verify that the second argument to the builtin is the last argument of the 645 // current function or method. 646 bool SecondArgIsLastNamedArgument = false; 647 const Expr *Arg = TheCall->getArg(1)->IgnoreParenCasts(); 648 649 if (const DeclRefExpr *DR = dyn_cast<DeclRefExpr>(Arg)) { 650 if (const ParmVarDecl *PV = dyn_cast<ParmVarDecl>(DR->getDecl())) { 651 // FIXME: This isn't correct for methods (results in bogus warning). 652 // Get the last formal in the current function. 653 const ParmVarDecl *LastArg; 654 if (CurBlock) 655 LastArg = *(CurBlock->TheDecl->param_end()-1); 656 else if (FunctionDecl *FD = getCurFunctionDecl()) 657 LastArg = *(FD->param_end()-1); 658 else 659 LastArg = *(getCurMethodDecl()->param_end()-1); 660 SecondArgIsLastNamedArgument = PV == LastArg; 661 } 662 } 663 664 if (!SecondArgIsLastNamedArgument) 665 Diag(TheCall->getArg(1)->getLocStart(), 666 diag::warn_second_parameter_of_va_start_not_last_named_argument); 667 return false; 668} 669 670/// SemaBuiltinUnorderedCompare - Handle functions like __builtin_isgreater and 671/// friends. This is declared to take (...), so we have to check everything. 672bool Sema::SemaBuiltinUnorderedCompare(CallExpr *TheCall) { 673 if (TheCall->getNumArgs() < 2) 674 return Diag(TheCall->getLocEnd(), diag::err_typecheck_call_too_few_args) 675 << 0 << 2 << TheCall->getNumArgs()/*function call*/; 676 if (TheCall->getNumArgs() > 2) 677 return Diag(TheCall->getArg(2)->getLocStart(), 678 diag::err_typecheck_call_too_many_args) 679 << 0 /*function call*/ << 2 << TheCall->getNumArgs() 680 << SourceRange(TheCall->getArg(2)->getLocStart(), 681 (*(TheCall->arg_end()-1))->getLocEnd()); 682 683 Expr *OrigArg0 = TheCall->getArg(0); 684 Expr *OrigArg1 = TheCall->getArg(1); 685 686 // Do standard promotions between the two arguments, returning their common 687 // type. 688 QualType Res = UsualArithmeticConversions(OrigArg0, OrigArg1, false); 689 690 // Make sure any conversions are pushed back into the call; this is 691 // type safe since unordered compare builtins are declared as "_Bool 692 // foo(...)". 693 TheCall->setArg(0, OrigArg0); 694 TheCall->setArg(1, OrigArg1); 695 696 if (OrigArg0->isTypeDependent() || OrigArg1->isTypeDependent()) 697 return false; 698 699 // If the common type isn't a real floating type, then the arguments were 700 // invalid for this operation. 701 if (!Res->isRealFloatingType()) 702 return Diag(OrigArg0->getLocStart(), 703 diag::err_typecheck_call_invalid_ordered_compare) 704 << OrigArg0->getType() << OrigArg1->getType() 705 << SourceRange(OrigArg0->getLocStart(), OrigArg1->getLocEnd()); 706 707 return false; 708} 709 710/// SemaBuiltinSemaBuiltinFPClassification - Handle functions like 711/// __builtin_isnan and friends. This is declared to take (...), so we have 712/// to check everything. We expect the last argument to be a floating point 713/// value. 714bool Sema::SemaBuiltinFPClassification(CallExpr *TheCall, unsigned NumArgs) { 715 if (TheCall->getNumArgs() < NumArgs) 716 return Diag(TheCall->getLocEnd(), diag::err_typecheck_call_too_few_args) 717 << 0 << NumArgs << TheCall->getNumArgs()/*function call*/; 718 if (TheCall->getNumArgs() > NumArgs) 719 return Diag(TheCall->getArg(NumArgs)->getLocStart(), 720 diag::err_typecheck_call_too_many_args) 721 << 0 /*function call*/ << NumArgs << TheCall->getNumArgs() 722 << SourceRange(TheCall->getArg(NumArgs)->getLocStart(), 723 (*(TheCall->arg_end()-1))->getLocEnd()); 724 725 Expr *OrigArg = TheCall->getArg(NumArgs-1); 726 727 if (OrigArg->isTypeDependent()) 728 return false; 729 730 // This operation requires a non-_Complex floating-point number. 731 if (!OrigArg->getType()->isRealFloatingType()) 732 return Diag(OrigArg->getLocStart(), 733 diag::err_typecheck_call_invalid_unary_fp) 734 << OrigArg->getType() << OrigArg->getSourceRange(); 735 736 // If this is an implicit conversion from float -> double, remove it. 737 if (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(OrigArg)) { 738 Expr *CastArg = Cast->getSubExpr(); 739 if (CastArg->getType()->isSpecificBuiltinType(BuiltinType::Float)) { 740 assert(Cast->getType()->isSpecificBuiltinType(BuiltinType::Double) && 741 "promotion from float to double is the only expected cast here"); 742 Cast->setSubExpr(0); 743 TheCall->setArg(NumArgs-1, CastArg); 744 OrigArg = CastArg; 745 } 746 } 747 748 return false; 749} 750 751/// SemaBuiltinShuffleVector - Handle __builtin_shufflevector. 752// This is declared to take (...), so we have to check everything. 753ExprResult Sema::SemaBuiltinShuffleVector(CallExpr *TheCall) { 754 if (TheCall->getNumArgs() < 2) 755 return ExprError(Diag(TheCall->getLocEnd(), 756 diag::err_typecheck_call_too_few_args_at_least) 757 << 0 /*function call*/ << 2 << TheCall->getNumArgs() 758 << TheCall->getSourceRange()); 759 760 // Determine which of the following types of shufflevector we're checking: 761 // 1) unary, vector mask: (lhs, mask) 762 // 2) binary, vector mask: (lhs, rhs, mask) 763 // 3) binary, scalar mask: (lhs, rhs, index, ..., index) 764 QualType resType = TheCall->getArg(0)->getType(); 765 unsigned numElements = 0; 766 767 if (!TheCall->getArg(0)->isTypeDependent() && 768 !TheCall->getArg(1)->isTypeDependent()) { 769 QualType LHSType = TheCall->getArg(0)->getType(); 770 QualType RHSType = TheCall->getArg(1)->getType(); 771 772 if (!LHSType->isVectorType() || !RHSType->isVectorType()) { 773 Diag(TheCall->getLocStart(), diag::err_shufflevector_non_vector) 774 << SourceRange(TheCall->getArg(0)->getLocStart(), 775 TheCall->getArg(1)->getLocEnd()); 776 return ExprError(); 777 } 778 779 numElements = LHSType->getAs<VectorType>()->getNumElements(); 780 unsigned numResElements = TheCall->getNumArgs() - 2; 781 782 // Check to see if we have a call with 2 vector arguments, the unary shuffle 783 // with mask. If so, verify that RHS is an integer vector type with the 784 // same number of elts as lhs. 785 if (TheCall->getNumArgs() == 2) { 786 if (!RHSType->hasIntegerRepresentation() || 787 RHSType->getAs<VectorType>()->getNumElements() != numElements) 788 Diag(TheCall->getLocStart(), diag::err_shufflevector_incompatible_vector) 789 << SourceRange(TheCall->getArg(1)->getLocStart(), 790 TheCall->getArg(1)->getLocEnd()); 791 numResElements = numElements; 792 } 793 else if (!Context.hasSameUnqualifiedType(LHSType, RHSType)) { 794 Diag(TheCall->getLocStart(), diag::err_shufflevector_incompatible_vector) 795 << SourceRange(TheCall->getArg(0)->getLocStart(), 796 TheCall->getArg(1)->getLocEnd()); 797 return ExprError(); 798 } else if (numElements != numResElements) { 799 QualType eltType = LHSType->getAs<VectorType>()->getElementType(); 800 resType = Context.getVectorType(eltType, numResElements, 801 VectorType::NotAltiVec); 802 } 803 } 804 805 for (unsigned i = 2; i < TheCall->getNumArgs(); i++) { 806 if (TheCall->getArg(i)->isTypeDependent() || 807 TheCall->getArg(i)->isValueDependent()) 808 continue; 809 810 llvm::APSInt Result(32); 811 if (!TheCall->getArg(i)->isIntegerConstantExpr(Result, Context)) 812 return ExprError(Diag(TheCall->getLocStart(), 813 diag::err_shufflevector_nonconstant_argument) 814 << TheCall->getArg(i)->getSourceRange()); 815 816 if (Result.getActiveBits() > 64 || Result.getZExtValue() >= numElements*2) 817 return ExprError(Diag(TheCall->getLocStart(), 818 diag::err_shufflevector_argument_too_large) 819 << TheCall->getArg(i)->getSourceRange()); 820 } 821 822 llvm::SmallVector<Expr*, 32> exprs; 823 824 for (unsigned i = 0, e = TheCall->getNumArgs(); i != e; i++) { 825 exprs.push_back(TheCall->getArg(i)); 826 TheCall->setArg(i, 0); 827 } 828 829 return Owned(new (Context) ShuffleVectorExpr(Context, exprs.begin(), 830 exprs.size(), resType, 831 TheCall->getCallee()->getLocStart(), 832 TheCall->getRParenLoc())); 833} 834 835/// SemaBuiltinPrefetch - Handle __builtin_prefetch. 836// This is declared to take (const void*, ...) and can take two 837// optional constant int args. 838bool Sema::SemaBuiltinPrefetch(CallExpr *TheCall) { 839 unsigned NumArgs = TheCall->getNumArgs(); 840 841 if (NumArgs > 3) 842 return Diag(TheCall->getLocEnd(), 843 diag::err_typecheck_call_too_many_args_at_most) 844 << 0 /*function call*/ << 3 << NumArgs 845 << TheCall->getSourceRange(); 846 847 // Argument 0 is checked for us and the remaining arguments must be 848 // constant integers. 849 for (unsigned i = 1; i != NumArgs; ++i) { 850 Expr *Arg = TheCall->getArg(i); 851 852 llvm::APSInt Result; 853 if (SemaBuiltinConstantArg(TheCall, i, Result)) 854 return true; 855 856 // FIXME: gcc issues a warning and rewrites these to 0. These 857 // seems especially odd for the third argument since the default 858 // is 3. 859 if (i == 1) { 860 if (Result.getLimitedValue() > 1) 861 return Diag(TheCall->getLocStart(), diag::err_argument_invalid_range) 862 << "0" << "1" << Arg->getSourceRange(); 863 } else { 864 if (Result.getLimitedValue() > 3) 865 return Diag(TheCall->getLocStart(), diag::err_argument_invalid_range) 866 << "0" << "3" << Arg->getSourceRange(); 867 } 868 } 869 870 return false; 871} 872 873/// SemaBuiltinConstantArg - Handle a check if argument ArgNum of CallExpr 874/// TheCall is a constant expression. 875bool Sema::SemaBuiltinConstantArg(CallExpr *TheCall, int ArgNum, 876 llvm::APSInt &Result) { 877 Expr *Arg = TheCall->getArg(ArgNum); 878 DeclRefExpr *DRE =cast<DeclRefExpr>(TheCall->getCallee()->IgnoreParenCasts()); 879 FunctionDecl *FDecl = cast<FunctionDecl>(DRE->getDecl()); 880 881 if (Arg->isTypeDependent() || Arg->isValueDependent()) return false; 882 883 if (!Arg->isIntegerConstantExpr(Result, Context)) 884 return Diag(TheCall->getLocStart(), diag::err_constant_integer_arg_type) 885 << FDecl->getDeclName() << Arg->getSourceRange(); 886 887 return false; 888} 889 890/// SemaBuiltinObjectSize - Handle __builtin_object_size(void *ptr, 891/// int type). This simply type checks that type is one of the defined 892/// constants (0-3). 893// For compatability check 0-3, llvm only handles 0 and 2. 894bool Sema::SemaBuiltinObjectSize(CallExpr *TheCall) { 895 llvm::APSInt Result; 896 897 // Check constant-ness first. 898 if (SemaBuiltinConstantArg(TheCall, 1, Result)) 899 return true; 900 901 Expr *Arg = TheCall->getArg(1); 902 if (Result.getSExtValue() < 0 || Result.getSExtValue() > 3) { 903 return Diag(TheCall->getLocStart(), diag::err_argument_invalid_range) 904 << "0" << "3" << SourceRange(Arg->getLocStart(), Arg->getLocEnd()); 905 } 906 907 return false; 908} 909 910/// SemaBuiltinLongjmp - Handle __builtin_longjmp(void *env[5], int val). 911/// This checks that val is a constant 1. 912bool Sema::SemaBuiltinLongjmp(CallExpr *TheCall) { 913 Expr *Arg = TheCall->getArg(1); 914 llvm::APSInt Result; 915 916 // TODO: This is less than ideal. Overload this to take a value. 917 if (SemaBuiltinConstantArg(TheCall, 1, Result)) 918 return true; 919 920 if (Result != 1) 921 return Diag(TheCall->getLocStart(), diag::err_builtin_longjmp_invalid_val) 922 << SourceRange(Arg->getLocStart(), Arg->getLocEnd()); 923 924 return false; 925} 926 927// Handle i > 1 ? "x" : "y", recursivelly 928bool Sema::SemaCheckStringLiteral(const Expr *E, const CallExpr *TheCall, 929 bool HasVAListArg, 930 unsigned format_idx, unsigned firstDataArg, 931 bool isPrintf) { 932 933 if (E->isTypeDependent() || E->isValueDependent()) 934 return false; 935 936 switch (E->getStmtClass()) { 937 case Stmt::ConditionalOperatorClass: { 938 const ConditionalOperator *C = cast<ConditionalOperator>(E); 939 return SemaCheckStringLiteral(C->getTrueExpr(), TheCall, HasVAListArg, 940 format_idx, firstDataArg, isPrintf) 941 && SemaCheckStringLiteral(C->getRHS(), TheCall, HasVAListArg, 942 format_idx, firstDataArg, isPrintf); 943 } 944 945 case Stmt::ImplicitCastExprClass: { 946 const ImplicitCastExpr *Expr = cast<ImplicitCastExpr>(E); 947 return SemaCheckStringLiteral(Expr->getSubExpr(), TheCall, HasVAListArg, 948 format_idx, firstDataArg, isPrintf); 949 } 950 951 case Stmt::ParenExprClass: { 952 const ParenExpr *Expr = cast<ParenExpr>(E); 953 return SemaCheckStringLiteral(Expr->getSubExpr(), TheCall, HasVAListArg, 954 format_idx, firstDataArg, isPrintf); 955 } 956 957 case Stmt::DeclRefExprClass: { 958 const DeclRefExpr *DR = cast<DeclRefExpr>(E); 959 960 // As an exception, do not flag errors for variables binding to 961 // const string literals. 962 if (const VarDecl *VD = dyn_cast<VarDecl>(DR->getDecl())) { 963 bool isConstant = false; 964 QualType T = DR->getType(); 965 966 if (const ArrayType *AT = Context.getAsArrayType(T)) { 967 isConstant = AT->getElementType().isConstant(Context); 968 } else if (const PointerType *PT = T->getAs<PointerType>()) { 969 isConstant = T.isConstant(Context) && 970 PT->getPointeeType().isConstant(Context); 971 } 972 973 if (isConstant) { 974 if (const Expr *Init = VD->getAnyInitializer()) 975 return SemaCheckStringLiteral(Init, TheCall, 976 HasVAListArg, format_idx, firstDataArg, 977 isPrintf); 978 } 979 980 // For vprintf* functions (i.e., HasVAListArg==true), we add a 981 // special check to see if the format string is a function parameter 982 // of the function calling the printf function. If the function 983 // has an attribute indicating it is a printf-like function, then we 984 // should suppress warnings concerning non-literals being used in a call 985 // to a vprintf function. For example: 986 // 987 // void 988 // logmessage(char const *fmt __attribute__ (format (printf, 1, 2)), ...){ 989 // va_list ap; 990 // va_start(ap, fmt); 991 // vprintf(fmt, ap); // Do NOT emit a warning about "fmt". 992 // ... 993 // 994 // 995 // FIXME: We don't have full attribute support yet, so just check to see 996 // if the argument is a DeclRefExpr that references a parameter. We'll 997 // add proper support for checking the attribute later. 998 if (HasVAListArg) 999 if (isa<ParmVarDecl>(VD)) 1000 return true; 1001 } 1002 1003 return false; 1004 } 1005 1006 case Stmt::CallExprClass: { 1007 const CallExpr *CE = cast<CallExpr>(E); 1008 if (const ImplicitCastExpr *ICE 1009 = dyn_cast<ImplicitCastExpr>(CE->getCallee())) { 1010 if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ICE->getSubExpr())) { 1011 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1012 if (const FormatArgAttr *FA = FD->getAttr<FormatArgAttr>()) { 1013 unsigned ArgIndex = FA->getFormatIdx(); 1014 const Expr *Arg = CE->getArg(ArgIndex - 1); 1015 1016 return SemaCheckStringLiteral(Arg, TheCall, HasVAListArg, 1017 format_idx, firstDataArg, isPrintf); 1018 } 1019 } 1020 } 1021 } 1022 1023 return false; 1024 } 1025 case Stmt::ObjCStringLiteralClass: 1026 case Stmt::StringLiteralClass: { 1027 const StringLiteral *StrE = NULL; 1028 1029 if (const ObjCStringLiteral *ObjCFExpr = dyn_cast<ObjCStringLiteral>(E)) 1030 StrE = ObjCFExpr->getString(); 1031 else 1032 StrE = cast<StringLiteral>(E); 1033 1034 if (StrE) { 1035 CheckFormatString(StrE, E, TheCall, HasVAListArg, format_idx, 1036 firstDataArg, isPrintf); 1037 return true; 1038 } 1039 1040 return false; 1041 } 1042 1043 default: 1044 return false; 1045 } 1046} 1047 1048void 1049Sema::CheckNonNullArguments(const NonNullAttr *NonNull, 1050 const CallExpr *TheCall) { 1051 for (NonNullAttr::args_iterator i = NonNull->args_begin(), 1052 e = NonNull->args_end(); 1053 i != e; ++i) { 1054 const Expr *ArgExpr = TheCall->getArg(*i); 1055 if (ArgExpr->isNullPointerConstant(Context, 1056 Expr::NPC_ValueDependentIsNotNull)) 1057 Diag(TheCall->getCallee()->getLocStart(), diag::warn_null_arg) 1058 << ArgExpr->getSourceRange(); 1059 } 1060} 1061 1062/// CheckPrintfScanfArguments - Check calls to printf and scanf (and similar 1063/// functions) for correct use of format strings. 1064void 1065Sema::CheckPrintfScanfArguments(const CallExpr *TheCall, bool HasVAListArg, 1066 unsigned format_idx, unsigned firstDataArg, 1067 bool isPrintf) { 1068 1069 const Expr *Fn = TheCall->getCallee(); 1070 1071 // The way the format attribute works in GCC, the implicit this argument 1072 // of member functions is counted. However, it doesn't appear in our own 1073 // lists, so decrement format_idx in that case. 1074 if (isa<CXXMemberCallExpr>(TheCall)) { 1075 // Catch a format attribute mistakenly referring to the object argument. 1076 if (format_idx == 0) 1077 return; 1078 --format_idx; 1079 if(firstDataArg != 0) 1080 --firstDataArg; 1081 } 1082 1083 // CHECK: printf/scanf-like function is called with no format string. 1084 if (format_idx >= TheCall->getNumArgs()) { 1085 Diag(TheCall->getRParenLoc(), diag::warn_missing_format_string) 1086 << Fn->getSourceRange(); 1087 return; 1088 } 1089 1090 const Expr *OrigFormatExpr = TheCall->getArg(format_idx)->IgnoreParenCasts(); 1091 1092 // CHECK: format string is not a string literal. 1093 // 1094 // Dynamically generated format strings are difficult to 1095 // automatically vet at compile time. Requiring that format strings 1096 // are string literals: (1) permits the checking of format strings by 1097 // the compiler and thereby (2) can practically remove the source of 1098 // many format string exploits. 1099 1100 // Format string can be either ObjC string (e.g. @"%d") or 1101 // C string (e.g. "%d") 1102 // ObjC string uses the same format specifiers as C string, so we can use 1103 // the same format string checking logic for both ObjC and C strings. 1104 if (SemaCheckStringLiteral(OrigFormatExpr, TheCall, HasVAListArg, format_idx, 1105 firstDataArg, isPrintf)) 1106 return; // Literal format string found, check done! 1107 1108 // If there are no arguments specified, warn with -Wformat-security, otherwise 1109 // warn only with -Wformat-nonliteral. 1110 if (TheCall->getNumArgs() == format_idx+1) 1111 Diag(TheCall->getArg(format_idx)->getLocStart(), 1112 diag::warn_format_nonliteral_noargs) 1113 << OrigFormatExpr->getSourceRange(); 1114 else 1115 Diag(TheCall->getArg(format_idx)->getLocStart(), 1116 diag::warn_format_nonliteral) 1117 << OrigFormatExpr->getSourceRange(); 1118} 1119 1120namespace { 1121class CheckFormatHandler : public analyze_format_string::FormatStringHandler { 1122protected: 1123 Sema &S; 1124 const StringLiteral *FExpr; 1125 const Expr *OrigFormatExpr; 1126 const unsigned FirstDataArg; 1127 const unsigned NumDataArgs; 1128 const bool IsObjCLiteral; 1129 const char *Beg; // Start of format string. 1130 const bool HasVAListArg; 1131 const CallExpr *TheCall; 1132 unsigned FormatIdx; 1133 llvm::BitVector CoveredArgs; 1134 bool usesPositionalArgs; 1135 bool atFirstArg; 1136public: 1137 CheckFormatHandler(Sema &s, const StringLiteral *fexpr, 1138 const Expr *origFormatExpr, unsigned firstDataArg, 1139 unsigned numDataArgs, bool isObjCLiteral, 1140 const char *beg, bool hasVAListArg, 1141 const CallExpr *theCall, unsigned formatIdx) 1142 : S(s), FExpr(fexpr), OrigFormatExpr(origFormatExpr), 1143 FirstDataArg(firstDataArg), 1144 NumDataArgs(numDataArgs), 1145 IsObjCLiteral(isObjCLiteral), Beg(beg), 1146 HasVAListArg(hasVAListArg), 1147 TheCall(theCall), FormatIdx(formatIdx), 1148 usesPositionalArgs(false), atFirstArg(true) { 1149 CoveredArgs.resize(numDataArgs); 1150 CoveredArgs.reset(); 1151 } 1152 1153 void DoneProcessing(); 1154 1155 void HandleIncompleteSpecifier(const char *startSpecifier, 1156 unsigned specifierLen); 1157 1158 virtual void HandleInvalidPosition(const char *startSpecifier, 1159 unsigned specifierLen, 1160 analyze_format_string::PositionContext p); 1161 1162 virtual void HandleZeroPosition(const char *startPos, unsigned posLen); 1163 1164 void HandleNullChar(const char *nullCharacter); 1165 1166protected: 1167 bool HandleInvalidConversionSpecifier(unsigned argIndex, SourceLocation Loc, 1168 const char *startSpec, 1169 unsigned specifierLen, 1170 const char *csStart, unsigned csLen); 1171 1172 SourceRange getFormatStringRange(); 1173 CharSourceRange getSpecifierRange(const char *startSpecifier, 1174 unsigned specifierLen); 1175 SourceLocation getLocationOfByte(const char *x); 1176 1177 const Expr *getDataArg(unsigned i) const; 1178 1179 bool CheckNumArgs(const analyze_format_string::FormatSpecifier &FS, 1180 const analyze_format_string::ConversionSpecifier &CS, 1181 const char *startSpecifier, unsigned specifierLen, 1182 unsigned argIndex); 1183}; 1184} 1185 1186SourceRange CheckFormatHandler::getFormatStringRange() { 1187 return OrigFormatExpr->getSourceRange(); 1188} 1189 1190CharSourceRange CheckFormatHandler:: 1191getSpecifierRange(const char *startSpecifier, unsigned specifierLen) { 1192 SourceLocation Start = getLocationOfByte(startSpecifier); 1193 SourceLocation End = getLocationOfByte(startSpecifier + specifierLen - 1); 1194 1195 // Advance the end SourceLocation by one due to half-open ranges. 1196 End = End.getFileLocWithOffset(1); 1197 1198 return CharSourceRange::getCharRange(Start, End); 1199} 1200 1201SourceLocation CheckFormatHandler::getLocationOfByte(const char *x) { 1202 return S.getLocationOfStringLiteralByte(FExpr, x - Beg); 1203} 1204 1205void CheckFormatHandler::HandleIncompleteSpecifier(const char *startSpecifier, 1206 unsigned specifierLen){ 1207 SourceLocation Loc = getLocationOfByte(startSpecifier); 1208 S.Diag(Loc, diag::warn_printf_incomplete_specifier) 1209 << getSpecifierRange(startSpecifier, specifierLen); 1210} 1211 1212void 1213CheckFormatHandler::HandleInvalidPosition(const char *startPos, unsigned posLen, 1214 analyze_format_string::PositionContext p) { 1215 SourceLocation Loc = getLocationOfByte(startPos); 1216 S.Diag(Loc, diag::warn_format_invalid_positional_specifier) 1217 << (unsigned) p << getSpecifierRange(startPos, posLen); 1218} 1219 1220void CheckFormatHandler::HandleZeroPosition(const char *startPos, 1221 unsigned posLen) { 1222 SourceLocation Loc = getLocationOfByte(startPos); 1223 S.Diag(Loc, diag::warn_format_zero_positional_specifier) 1224 << getSpecifierRange(startPos, posLen); 1225} 1226 1227void CheckFormatHandler::HandleNullChar(const char *nullCharacter) { 1228 // The presence of a null character is likely an error. 1229 S.Diag(getLocationOfByte(nullCharacter), 1230 diag::warn_printf_format_string_contains_null_char) 1231 << getFormatStringRange(); 1232} 1233 1234const Expr *CheckFormatHandler::getDataArg(unsigned i) const { 1235 return TheCall->getArg(FirstDataArg + i); 1236} 1237 1238void CheckFormatHandler::DoneProcessing() { 1239 // Does the number of data arguments exceed the number of 1240 // format conversions in the format string? 1241 if (!HasVAListArg) { 1242 // Find any arguments that weren't covered. 1243 CoveredArgs.flip(); 1244 signed notCoveredArg = CoveredArgs.find_first(); 1245 if (notCoveredArg >= 0) { 1246 assert((unsigned)notCoveredArg < NumDataArgs); 1247 S.Diag(getDataArg((unsigned) notCoveredArg)->getLocStart(), 1248 diag::warn_printf_data_arg_not_used) 1249 << getFormatStringRange(); 1250 } 1251 } 1252} 1253 1254bool 1255CheckFormatHandler::HandleInvalidConversionSpecifier(unsigned argIndex, 1256 SourceLocation Loc, 1257 const char *startSpec, 1258 unsigned specifierLen, 1259 const char *csStart, 1260 unsigned csLen) { 1261 1262 bool keepGoing = true; 1263 if (argIndex < NumDataArgs) { 1264 // Consider the argument coverered, even though the specifier doesn't 1265 // make sense. 1266 CoveredArgs.set(argIndex); 1267 } 1268 else { 1269 // If argIndex exceeds the number of data arguments we 1270 // don't issue a warning because that is just a cascade of warnings (and 1271 // they may have intended '%%' anyway). We don't want to continue processing 1272 // the format string after this point, however, as we will like just get 1273 // gibberish when trying to match arguments. 1274 keepGoing = false; 1275 } 1276 1277 S.Diag(Loc, diag::warn_format_invalid_conversion) 1278 << llvm::StringRef(csStart, csLen) 1279 << getSpecifierRange(startSpec, specifierLen); 1280 1281 return keepGoing; 1282} 1283 1284bool 1285CheckFormatHandler::CheckNumArgs( 1286 const analyze_format_string::FormatSpecifier &FS, 1287 const analyze_format_string::ConversionSpecifier &CS, 1288 const char *startSpecifier, unsigned specifierLen, unsigned argIndex) { 1289 1290 if (argIndex >= NumDataArgs) { 1291 if (FS.usesPositionalArg()) { 1292 S.Diag(getLocationOfByte(CS.getStart()), 1293 diag::warn_printf_positional_arg_exceeds_data_args) 1294 << (argIndex+1) << NumDataArgs 1295 << getSpecifierRange(startSpecifier, specifierLen); 1296 } 1297 else { 1298 S.Diag(getLocationOfByte(CS.getStart()), 1299 diag::warn_printf_insufficient_data_args) 1300 << getSpecifierRange(startSpecifier, specifierLen); 1301 } 1302 1303 return false; 1304 } 1305 return true; 1306} 1307 1308//===--- CHECK: Printf format string checking ------------------------------===// 1309 1310namespace { 1311class CheckPrintfHandler : public CheckFormatHandler { 1312public: 1313 CheckPrintfHandler(Sema &s, const StringLiteral *fexpr, 1314 const Expr *origFormatExpr, unsigned firstDataArg, 1315 unsigned numDataArgs, bool isObjCLiteral, 1316 const char *beg, bool hasVAListArg, 1317 const CallExpr *theCall, unsigned formatIdx) 1318 : CheckFormatHandler(s, fexpr, origFormatExpr, firstDataArg, 1319 numDataArgs, isObjCLiteral, beg, hasVAListArg, 1320 theCall, formatIdx) {} 1321 1322 1323 bool HandleInvalidPrintfConversionSpecifier( 1324 const analyze_printf::PrintfSpecifier &FS, 1325 const char *startSpecifier, 1326 unsigned specifierLen); 1327 1328 bool HandlePrintfSpecifier(const analyze_printf::PrintfSpecifier &FS, 1329 const char *startSpecifier, 1330 unsigned specifierLen); 1331 1332 bool HandleAmount(const analyze_format_string::OptionalAmount &Amt, unsigned k, 1333 const char *startSpecifier, unsigned specifierLen); 1334 void HandleInvalidAmount(const analyze_printf::PrintfSpecifier &FS, 1335 const analyze_printf::OptionalAmount &Amt, 1336 unsigned type, 1337 const char *startSpecifier, unsigned specifierLen); 1338 void HandleFlag(const analyze_printf::PrintfSpecifier &FS, 1339 const analyze_printf::OptionalFlag &flag, 1340 const char *startSpecifier, unsigned specifierLen); 1341 void HandleIgnoredFlag(const analyze_printf::PrintfSpecifier &FS, 1342 const analyze_printf::OptionalFlag &ignoredFlag, 1343 const analyze_printf::OptionalFlag &flag, 1344 const char *startSpecifier, unsigned specifierLen); 1345}; 1346} 1347 1348bool CheckPrintfHandler::HandleInvalidPrintfConversionSpecifier( 1349 const analyze_printf::PrintfSpecifier &FS, 1350 const char *startSpecifier, 1351 unsigned specifierLen) { 1352 const analyze_printf::PrintfConversionSpecifier &CS = 1353 FS.getConversionSpecifier(); 1354 1355 return HandleInvalidConversionSpecifier(FS.getArgIndex(), 1356 getLocationOfByte(CS.getStart()), 1357 startSpecifier, specifierLen, 1358 CS.getStart(), CS.getLength()); 1359} 1360 1361bool CheckPrintfHandler::HandleAmount( 1362 const analyze_format_string::OptionalAmount &Amt, 1363 unsigned k, const char *startSpecifier, 1364 unsigned specifierLen) { 1365 1366 if (Amt.hasDataArgument()) { 1367 if (!HasVAListArg) { 1368 unsigned argIndex = Amt.getArgIndex(); 1369 if (argIndex >= NumDataArgs) { 1370 S.Diag(getLocationOfByte(Amt.getStart()), 1371 diag::warn_printf_asterisk_missing_arg) 1372 << k << getSpecifierRange(startSpecifier, specifierLen); 1373 // Don't do any more checking. We will just emit 1374 // spurious errors. 1375 return false; 1376 } 1377 1378 // Type check the data argument. It should be an 'int'. 1379 // Although not in conformance with C99, we also allow the argument to be 1380 // an 'unsigned int' as that is a reasonably safe case. GCC also 1381 // doesn't emit a warning for that case. 1382 CoveredArgs.set(argIndex); 1383 const Expr *Arg = getDataArg(argIndex); 1384 QualType T = Arg->getType(); 1385 1386 const analyze_printf::ArgTypeResult &ATR = Amt.getArgType(S.Context); 1387 assert(ATR.isValid()); 1388 1389 if (!ATR.matchesType(S.Context, T)) { 1390 S.Diag(getLocationOfByte(Amt.getStart()), 1391 diag::warn_printf_asterisk_wrong_type) 1392 << k 1393 << ATR.getRepresentativeType(S.Context) << T 1394 << getSpecifierRange(startSpecifier, specifierLen) 1395 << Arg->getSourceRange(); 1396 // Don't do any more checking. We will just emit 1397 // spurious errors. 1398 return false; 1399 } 1400 } 1401 } 1402 return true; 1403} 1404 1405void CheckPrintfHandler::HandleInvalidAmount( 1406 const analyze_printf::PrintfSpecifier &FS, 1407 const analyze_printf::OptionalAmount &Amt, 1408 unsigned type, 1409 const char *startSpecifier, 1410 unsigned specifierLen) { 1411 const analyze_printf::PrintfConversionSpecifier &CS = 1412 FS.getConversionSpecifier(); 1413 switch (Amt.getHowSpecified()) { 1414 case analyze_printf::OptionalAmount::Constant: 1415 S.Diag(getLocationOfByte(Amt.getStart()), 1416 diag::warn_printf_nonsensical_optional_amount) 1417 << type 1418 << CS.toString() 1419 << getSpecifierRange(startSpecifier, specifierLen) 1420 << FixItHint::CreateRemoval(getSpecifierRange(Amt.getStart(), 1421 Amt.getConstantLength())); 1422 break; 1423 1424 default: 1425 S.Diag(getLocationOfByte(Amt.getStart()), 1426 diag::warn_printf_nonsensical_optional_amount) 1427 << type 1428 << CS.toString() 1429 << getSpecifierRange(startSpecifier, specifierLen); 1430 break; 1431 } 1432} 1433 1434void CheckPrintfHandler::HandleFlag(const analyze_printf::PrintfSpecifier &FS, 1435 const analyze_printf::OptionalFlag &flag, 1436 const char *startSpecifier, 1437 unsigned specifierLen) { 1438 // Warn about pointless flag with a fixit removal. 1439 const analyze_printf::PrintfConversionSpecifier &CS = 1440 FS.getConversionSpecifier(); 1441 S.Diag(getLocationOfByte(flag.getPosition()), 1442 diag::warn_printf_nonsensical_flag) 1443 << flag.toString() << CS.toString() 1444 << getSpecifierRange(startSpecifier, specifierLen) 1445 << FixItHint::CreateRemoval(getSpecifierRange(flag.getPosition(), 1)); 1446} 1447 1448void CheckPrintfHandler::HandleIgnoredFlag( 1449 const analyze_printf::PrintfSpecifier &FS, 1450 const analyze_printf::OptionalFlag &ignoredFlag, 1451 const analyze_printf::OptionalFlag &flag, 1452 const char *startSpecifier, 1453 unsigned specifierLen) { 1454 // Warn about ignored flag with a fixit removal. 1455 S.Diag(getLocationOfByte(ignoredFlag.getPosition()), 1456 diag::warn_printf_ignored_flag) 1457 << ignoredFlag.toString() << flag.toString() 1458 << getSpecifierRange(startSpecifier, specifierLen) 1459 << FixItHint::CreateRemoval(getSpecifierRange( 1460 ignoredFlag.getPosition(), 1)); 1461} 1462 1463bool 1464CheckPrintfHandler::HandlePrintfSpecifier(const analyze_printf::PrintfSpecifier 1465 &FS, 1466 const char *startSpecifier, 1467 unsigned specifierLen) { 1468 1469 using namespace analyze_format_string; 1470 using namespace analyze_printf; 1471 const PrintfConversionSpecifier &CS = FS.getConversionSpecifier(); 1472 1473 if (FS.consumesDataArgument()) { 1474 if (atFirstArg) { 1475 atFirstArg = false; 1476 usesPositionalArgs = FS.usesPositionalArg(); 1477 } 1478 else if (usesPositionalArgs != FS.usesPositionalArg()) { 1479 // Cannot mix-and-match positional and non-positional arguments. 1480 S.Diag(getLocationOfByte(CS.getStart()), 1481 diag::warn_format_mix_positional_nonpositional_args) 1482 << getSpecifierRange(startSpecifier, specifierLen); 1483 return false; 1484 } 1485 } 1486 1487 // First check if the field width, precision, and conversion specifier 1488 // have matching data arguments. 1489 if (!HandleAmount(FS.getFieldWidth(), /* field width */ 0, 1490 startSpecifier, specifierLen)) { 1491 return false; 1492 } 1493 1494 if (!HandleAmount(FS.getPrecision(), /* precision */ 1, 1495 startSpecifier, specifierLen)) { 1496 return false; 1497 } 1498 1499 if (!CS.consumesDataArgument()) { 1500 // FIXME: Technically specifying a precision or field width here 1501 // makes no sense. Worth issuing a warning at some point. 1502 return true; 1503 } 1504 1505 // Consume the argument. 1506 unsigned argIndex = FS.getArgIndex(); 1507 if (argIndex < NumDataArgs) { 1508 // The check to see if the argIndex is valid will come later. 1509 // We set the bit here because we may exit early from this 1510 // function if we encounter some other error. 1511 CoveredArgs.set(argIndex); 1512 } 1513 1514 // Check for using an Objective-C specific conversion specifier 1515 // in a non-ObjC literal. 1516 if (!IsObjCLiteral && CS.isObjCArg()) { 1517 return HandleInvalidPrintfConversionSpecifier(FS, startSpecifier, 1518 specifierLen); 1519 } 1520 1521 // Check for invalid use of field width 1522 if (!FS.hasValidFieldWidth()) { 1523 HandleInvalidAmount(FS, FS.getFieldWidth(), /* field width */ 0, 1524 startSpecifier, specifierLen); 1525 } 1526 1527 // Check for invalid use of precision 1528 if (!FS.hasValidPrecision()) { 1529 HandleInvalidAmount(FS, FS.getPrecision(), /* precision */ 1, 1530 startSpecifier, specifierLen); 1531 } 1532 1533 // Check each flag does not conflict with any other component. 1534 if (!FS.hasValidLeadingZeros()) 1535 HandleFlag(FS, FS.hasLeadingZeros(), startSpecifier, specifierLen); 1536 if (!FS.hasValidPlusPrefix()) 1537 HandleFlag(FS, FS.hasPlusPrefix(), startSpecifier, specifierLen); 1538 if (!FS.hasValidSpacePrefix()) 1539 HandleFlag(FS, FS.hasSpacePrefix(), startSpecifier, specifierLen); 1540 if (!FS.hasValidAlternativeForm()) 1541 HandleFlag(FS, FS.hasAlternativeForm(), startSpecifier, specifierLen); 1542 if (!FS.hasValidLeftJustified()) 1543 HandleFlag(FS, FS.isLeftJustified(), startSpecifier, specifierLen); 1544 1545 // Check that flags are not ignored by another flag 1546 if (FS.hasSpacePrefix() && FS.hasPlusPrefix()) // ' ' ignored by '+' 1547 HandleIgnoredFlag(FS, FS.hasSpacePrefix(), FS.hasPlusPrefix(), 1548 startSpecifier, specifierLen); 1549 if (FS.hasLeadingZeros() && FS.isLeftJustified()) // '0' ignored by '-' 1550 HandleIgnoredFlag(FS, FS.hasLeadingZeros(), FS.isLeftJustified(), 1551 startSpecifier, specifierLen); 1552 1553 // Check the length modifier is valid with the given conversion specifier. 1554 const LengthModifier &LM = FS.getLengthModifier(); 1555 if (!FS.hasValidLengthModifier()) 1556 S.Diag(getLocationOfByte(LM.getStart()), 1557 diag::warn_format_nonsensical_length) 1558 << LM.toString() << CS.toString() 1559 << getSpecifierRange(startSpecifier, specifierLen) 1560 << FixItHint::CreateRemoval(getSpecifierRange(LM.getStart(), 1561 LM.getLength())); 1562 1563 // Are we using '%n'? 1564 if (CS.getKind() == ConversionSpecifier::nArg) { 1565 // Issue a warning about this being a possible security issue. 1566 S.Diag(getLocationOfByte(CS.getStart()), diag::warn_printf_write_back) 1567 << getSpecifierRange(startSpecifier, specifierLen); 1568 // Continue checking the other format specifiers. 1569 return true; 1570 } 1571 1572 // The remaining checks depend on the data arguments. 1573 if (HasVAListArg) 1574 return true; 1575 1576 if (!CheckNumArgs(FS, CS, startSpecifier, specifierLen, argIndex)) 1577 return false; 1578 1579 // Now type check the data expression that matches the 1580 // format specifier. 1581 const Expr *Ex = getDataArg(argIndex); 1582 const analyze_printf::ArgTypeResult &ATR = FS.getArgType(S.Context); 1583 if (ATR.isValid() && !ATR.matchesType(S.Context, Ex->getType())) { 1584 // Check if we didn't match because of an implicit cast from a 'char' 1585 // or 'short' to an 'int'. This is done because printf is a varargs 1586 // function. 1587 if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(Ex)) 1588 if (ICE->getType() == S.Context.IntTy) 1589 if (ATR.matchesType(S.Context, ICE->getSubExpr()->getType())) 1590 return true; 1591 1592 // We may be able to offer a FixItHint if it is a supported type. 1593 PrintfSpecifier fixedFS = FS; 1594 bool success = fixedFS.fixType(Ex->getType()); 1595 1596 if (success) { 1597 // Get the fix string from the fixed format specifier 1598 llvm::SmallString<128> buf; 1599 llvm::raw_svector_ostream os(buf); 1600 fixedFS.toString(os); 1601 1602 // FIXME: getRepresentativeType() perhaps should return a string 1603 // instead of a QualType to better handle when the representative 1604 // type is 'wint_t' (which is defined in the system headers). 1605 S.Diag(getLocationOfByte(CS.getStart()), 1606 diag::warn_printf_conversion_argument_type_mismatch) 1607 << ATR.getRepresentativeType(S.Context) << Ex->getType() 1608 << getSpecifierRange(startSpecifier, specifierLen) 1609 << Ex->getSourceRange() 1610 << FixItHint::CreateReplacement( 1611 getSpecifierRange(startSpecifier, specifierLen), 1612 os.str()); 1613 } 1614 else { 1615 S.Diag(getLocationOfByte(CS.getStart()), 1616 diag::warn_printf_conversion_argument_type_mismatch) 1617 << ATR.getRepresentativeType(S.Context) << Ex->getType() 1618 << getSpecifierRange(startSpecifier, specifierLen) 1619 << Ex->getSourceRange(); 1620 } 1621 } 1622 1623 return true; 1624} 1625 1626//===--- CHECK: Scanf format string checking ------------------------------===// 1627 1628namespace { 1629class CheckScanfHandler : public CheckFormatHandler { 1630public: 1631 CheckScanfHandler(Sema &s, const StringLiteral *fexpr, 1632 const Expr *origFormatExpr, unsigned firstDataArg, 1633 unsigned numDataArgs, bool isObjCLiteral, 1634 const char *beg, bool hasVAListArg, 1635 const CallExpr *theCall, unsigned formatIdx) 1636 : CheckFormatHandler(s, fexpr, origFormatExpr, firstDataArg, 1637 numDataArgs, isObjCLiteral, beg, hasVAListArg, 1638 theCall, formatIdx) {} 1639 1640 bool HandleScanfSpecifier(const analyze_scanf::ScanfSpecifier &FS, 1641 const char *startSpecifier, 1642 unsigned specifierLen); 1643 1644 bool HandleInvalidScanfConversionSpecifier( 1645 const analyze_scanf::ScanfSpecifier &FS, 1646 const char *startSpecifier, 1647 unsigned specifierLen); 1648 1649 void HandleIncompleteScanList(const char *start, const char *end); 1650}; 1651} 1652 1653void CheckScanfHandler::HandleIncompleteScanList(const char *start, 1654 const char *end) { 1655 S.Diag(getLocationOfByte(end), diag::warn_scanf_scanlist_incomplete) 1656 << getSpecifierRange(start, end - start); 1657} 1658 1659bool CheckScanfHandler::HandleInvalidScanfConversionSpecifier( 1660 const analyze_scanf::ScanfSpecifier &FS, 1661 const char *startSpecifier, 1662 unsigned specifierLen) { 1663 1664 const analyze_scanf::ScanfConversionSpecifier &CS = 1665 FS.getConversionSpecifier(); 1666 1667 return HandleInvalidConversionSpecifier(FS.getArgIndex(), 1668 getLocationOfByte(CS.getStart()), 1669 startSpecifier, specifierLen, 1670 CS.getStart(), CS.getLength()); 1671} 1672 1673bool CheckScanfHandler::HandleScanfSpecifier( 1674 const analyze_scanf::ScanfSpecifier &FS, 1675 const char *startSpecifier, 1676 unsigned specifierLen) { 1677 1678 using namespace analyze_scanf; 1679 using namespace analyze_format_string; 1680 1681 const ScanfConversionSpecifier &CS = FS.getConversionSpecifier(); 1682 1683 // Handle case where '%' and '*' don't consume an argument. These shouldn't 1684 // be used to decide if we are using positional arguments consistently. 1685 if (FS.consumesDataArgument()) { 1686 if (atFirstArg) { 1687 atFirstArg = false; 1688 usesPositionalArgs = FS.usesPositionalArg(); 1689 } 1690 else if (usesPositionalArgs != FS.usesPositionalArg()) { 1691 // Cannot mix-and-match positional and non-positional arguments. 1692 S.Diag(getLocationOfByte(CS.getStart()), 1693 diag::warn_format_mix_positional_nonpositional_args) 1694 << getSpecifierRange(startSpecifier, specifierLen); 1695 return false; 1696 } 1697 } 1698 1699 // Check if the field with is non-zero. 1700 const OptionalAmount &Amt = FS.getFieldWidth(); 1701 if (Amt.getHowSpecified() == OptionalAmount::Constant) { 1702 if (Amt.getConstantAmount() == 0) { 1703 const CharSourceRange &R = getSpecifierRange(Amt.getStart(), 1704 Amt.getConstantLength()); 1705 S.Diag(getLocationOfByte(Amt.getStart()), 1706 diag::warn_scanf_nonzero_width) 1707 << R << FixItHint::CreateRemoval(R); 1708 } 1709 } 1710 1711 if (!FS.consumesDataArgument()) { 1712 // FIXME: Technically specifying a precision or field width here 1713 // makes no sense. Worth issuing a warning at some point. 1714 return true; 1715 } 1716 1717 // Consume the argument. 1718 unsigned argIndex = FS.getArgIndex(); 1719 if (argIndex < NumDataArgs) { 1720 // The check to see if the argIndex is valid will come later. 1721 // We set the bit here because we may exit early from this 1722 // function if we encounter some other error. 1723 CoveredArgs.set(argIndex); 1724 } 1725 1726 // Check the length modifier is valid with the given conversion specifier. 1727 const LengthModifier &LM = FS.getLengthModifier(); 1728 if (!FS.hasValidLengthModifier()) { 1729 S.Diag(getLocationOfByte(LM.getStart()), 1730 diag::warn_format_nonsensical_length) 1731 << LM.toString() << CS.toString() 1732 << getSpecifierRange(startSpecifier, specifierLen) 1733 << FixItHint::CreateRemoval(getSpecifierRange(LM.getStart(), 1734 LM.getLength())); 1735 } 1736 1737 // The remaining checks depend on the data arguments. 1738 if (HasVAListArg) 1739 return true; 1740 1741 if (!CheckNumArgs(FS, CS, startSpecifier, specifierLen, argIndex)) 1742 return false; 1743 1744 // FIXME: Check that the argument type matches the format specifier. 1745 1746 return true; 1747} 1748 1749void Sema::CheckFormatString(const StringLiteral *FExpr, 1750 const Expr *OrigFormatExpr, 1751 const CallExpr *TheCall, bool HasVAListArg, 1752 unsigned format_idx, unsigned firstDataArg, 1753 bool isPrintf) { 1754 1755 // CHECK: is the format string a wide literal? 1756 if (FExpr->isWide()) { 1757 Diag(FExpr->getLocStart(), 1758 diag::warn_format_string_is_wide_literal) 1759 << OrigFormatExpr->getSourceRange(); 1760 return; 1761 } 1762 1763 // Str - The format string. NOTE: this is NOT null-terminated! 1764 llvm::StringRef StrRef = FExpr->getString(); 1765 const char *Str = StrRef.data(); 1766 unsigned StrLen = StrRef.size(); 1767 1768 // CHECK: empty format string? 1769 if (StrLen == 0) { 1770 Diag(FExpr->getLocStart(), diag::warn_empty_format_string) 1771 << OrigFormatExpr->getSourceRange(); 1772 return; 1773 } 1774 1775 if (isPrintf) { 1776 CheckPrintfHandler H(*this, FExpr, OrigFormatExpr, firstDataArg, 1777 TheCall->getNumArgs() - firstDataArg, 1778 isa<ObjCStringLiteral>(OrigFormatExpr), Str, 1779 HasVAListArg, TheCall, format_idx); 1780 1781 if (!analyze_format_string::ParsePrintfString(H, Str, Str + StrLen)) 1782 H.DoneProcessing(); 1783 } 1784 else { 1785 CheckScanfHandler H(*this, FExpr, OrigFormatExpr, firstDataArg, 1786 TheCall->getNumArgs() - firstDataArg, 1787 isa<ObjCStringLiteral>(OrigFormatExpr), Str, 1788 HasVAListArg, TheCall, format_idx); 1789 1790 if (!analyze_format_string::ParseScanfString(H, Str, Str + StrLen)) 1791 H.DoneProcessing(); 1792 } 1793} 1794 1795//===--- CHECK: Return Address of Stack Variable --------------------------===// 1796 1797static DeclRefExpr* EvalVal(Expr *E); 1798static DeclRefExpr* EvalAddr(Expr* E); 1799 1800/// CheckReturnStackAddr - Check if a return statement returns the address 1801/// of a stack variable. 1802void 1803Sema::CheckReturnStackAddr(Expr *RetValExp, QualType lhsType, 1804 SourceLocation ReturnLoc) { 1805 1806 // Perform checking for returned stack addresses. 1807 if (lhsType->isPointerType() || lhsType->isBlockPointerType()) { 1808 if (DeclRefExpr *DR = EvalAddr(RetValExp)) 1809 Diag(DR->getLocStart(), diag::warn_ret_stack_addr) 1810 << DR->getDecl()->getDeclName() << RetValExp->getSourceRange(); 1811 1812 // Skip over implicit cast expressions when checking for block expressions. 1813 RetValExp = RetValExp->IgnoreParenCasts(); 1814 1815 if (BlockExpr *C = dyn_cast<BlockExpr>(RetValExp)) 1816 if (C->hasBlockDeclRefExprs()) 1817 Diag(C->getLocStart(), diag::err_ret_local_block) 1818 << C->getSourceRange(); 1819 1820 if (AddrLabelExpr *ALE = dyn_cast<AddrLabelExpr>(RetValExp)) 1821 Diag(ALE->getLocStart(), diag::warn_ret_addr_label) 1822 << ALE->getSourceRange(); 1823 1824 } else if (lhsType->isReferenceType()) { 1825 // Perform checking for stack values returned by reference. 1826 // Check for a reference to the stack 1827 if (DeclRefExpr *DR = EvalVal(RetValExp)) 1828 Diag(DR->getLocStart(), diag::warn_ret_stack_ref) 1829 << DR->getDecl()->getDeclName() << RetValExp->getSourceRange(); 1830 } 1831} 1832 1833/// EvalAddr - EvalAddr and EvalVal are mutually recursive functions that 1834/// check if the expression in a return statement evaluates to an address 1835/// to a location on the stack. The recursion is used to traverse the 1836/// AST of the return expression, with recursion backtracking when we 1837/// encounter a subexpression that (1) clearly does not lead to the address 1838/// of a stack variable or (2) is something we cannot determine leads to 1839/// the address of a stack variable based on such local checking. 1840/// 1841/// EvalAddr processes expressions that are pointers that are used as 1842/// references (and not L-values). EvalVal handles all other values. 1843/// At the base case of the recursion is a check for a DeclRefExpr* in 1844/// the refers to a stack variable. 1845/// 1846/// This implementation handles: 1847/// 1848/// * pointer-to-pointer casts 1849/// * implicit conversions from array references to pointers 1850/// * taking the address of fields 1851/// * arbitrary interplay between "&" and "*" operators 1852/// * pointer arithmetic from an address of a stack variable 1853/// * taking the address of an array element where the array is on the stack 1854static DeclRefExpr* EvalAddr(Expr *E) { 1855 // We should only be called for evaluating pointer expressions. 1856 assert((E->getType()->isAnyPointerType() || 1857 E->getType()->isBlockPointerType() || 1858 E->getType()->isObjCQualifiedIdType()) && 1859 "EvalAddr only works on pointers"); 1860 1861 // Our "symbolic interpreter" is just a dispatch off the currently 1862 // viewed AST node. We then recursively traverse the AST by calling 1863 // EvalAddr and EvalVal appropriately. 1864 switch (E->getStmtClass()) { 1865 case Stmt::ParenExprClass: 1866 // Ignore parentheses. 1867 return EvalAddr(cast<ParenExpr>(E)->getSubExpr()); 1868 1869 case Stmt::UnaryOperatorClass: { 1870 // The only unary operator that make sense to handle here 1871 // is AddrOf. All others don't make sense as pointers. 1872 UnaryOperator *U = cast<UnaryOperator>(E); 1873 1874 if (U->getOpcode() == UO_AddrOf) 1875 return EvalVal(U->getSubExpr()); 1876 else 1877 return NULL; 1878 } 1879 1880 case Stmt::BinaryOperatorClass: { 1881 // Handle pointer arithmetic. All other binary operators are not valid 1882 // in this context. 1883 BinaryOperator *B = cast<BinaryOperator>(E); 1884 BinaryOperatorKind op = B->getOpcode(); 1885 1886 if (op != BO_Add && op != BO_Sub) 1887 return NULL; 1888 1889 Expr *Base = B->getLHS(); 1890 1891 // Determine which argument is the real pointer base. It could be 1892 // the RHS argument instead of the LHS. 1893 if (!Base->getType()->isPointerType()) Base = B->getRHS(); 1894 1895 assert (Base->getType()->isPointerType()); 1896 return EvalAddr(Base); 1897 } 1898 1899 // For conditional operators we need to see if either the LHS or RHS are 1900 // valid DeclRefExpr*s. If one of them is valid, we return it. 1901 case Stmt::ConditionalOperatorClass: { 1902 ConditionalOperator *C = cast<ConditionalOperator>(E); 1903 1904 // Handle the GNU extension for missing LHS. 1905 if (Expr *lhsExpr = C->getLHS()) 1906 if (DeclRefExpr* LHS = EvalAddr(lhsExpr)) 1907 return LHS; 1908 1909 return EvalAddr(C->getRHS()); 1910 } 1911 1912 // For casts, we need to handle conversions from arrays to 1913 // pointer values, and pointer-to-pointer conversions. 1914 case Stmt::ImplicitCastExprClass: 1915 case Stmt::CStyleCastExprClass: 1916 case Stmt::CXXFunctionalCastExprClass: { 1917 Expr* SubExpr = cast<CastExpr>(E)->getSubExpr(); 1918 QualType T = SubExpr->getType(); 1919 1920 if (SubExpr->getType()->isPointerType() || 1921 SubExpr->getType()->isBlockPointerType() || 1922 SubExpr->getType()->isObjCQualifiedIdType()) 1923 return EvalAddr(SubExpr); 1924 else if (T->isArrayType()) 1925 return EvalVal(SubExpr); 1926 else 1927 return 0; 1928 } 1929 1930 // C++ casts. For dynamic casts, static casts, and const casts, we 1931 // are always converting from a pointer-to-pointer, so we just blow 1932 // through the cast. In the case the dynamic cast doesn't fail (and 1933 // return NULL), we take the conservative route and report cases 1934 // where we return the address of a stack variable. For Reinterpre 1935 // FIXME: The comment about is wrong; we're not always converting 1936 // from pointer to pointer. I'm guessing that this code should also 1937 // handle references to objects. 1938 case Stmt::CXXStaticCastExprClass: 1939 case Stmt::CXXDynamicCastExprClass: 1940 case Stmt::CXXConstCastExprClass: 1941 case Stmt::CXXReinterpretCastExprClass: { 1942 Expr *S = cast<CXXNamedCastExpr>(E)->getSubExpr(); 1943 if (S->getType()->isPointerType() || S->getType()->isBlockPointerType()) 1944 return EvalAddr(S); 1945 else 1946 return NULL; 1947 } 1948 1949 // Everything else: we simply don't reason about them. 1950 default: 1951 return NULL; 1952 } 1953} 1954 1955 1956/// EvalVal - This function is complements EvalAddr in the mutual recursion. 1957/// See the comments for EvalAddr for more details. 1958static DeclRefExpr* EvalVal(Expr *E) { 1959do { 1960 // We should only be called for evaluating non-pointer expressions, or 1961 // expressions with a pointer type that are not used as references but instead 1962 // are l-values (e.g., DeclRefExpr with a pointer type). 1963 1964 // Our "symbolic interpreter" is just a dispatch off the currently 1965 // viewed AST node. We then recursively traverse the AST by calling 1966 // EvalAddr and EvalVal appropriately. 1967 switch (E->getStmtClass()) { 1968 case Stmt::ImplicitCastExprClass: { 1969 ImplicitCastExpr *IE = cast<ImplicitCastExpr>(E); 1970 if (IE->getValueKind() == VK_LValue) { 1971 E = IE->getSubExpr(); 1972 continue; 1973 } 1974 return NULL; 1975 } 1976 1977 case Stmt::DeclRefExprClass: { 1978 // DeclRefExpr: the base case. When we hit a DeclRefExpr we are looking 1979 // at code that refers to a variable's name. We check if it has local 1980 // storage within the function, and if so, return the expression. 1981 DeclRefExpr *DR = cast<DeclRefExpr>(E); 1982 1983 if (VarDecl *V = dyn_cast<VarDecl>(DR->getDecl())) 1984 if (V->hasLocalStorage() && !V->getType()->isReferenceType()) return DR; 1985 1986 return NULL; 1987 } 1988 1989 case Stmt::ParenExprClass: { 1990 // Ignore parentheses. 1991 E = cast<ParenExpr>(E)->getSubExpr(); 1992 continue; 1993 } 1994 1995 case Stmt::UnaryOperatorClass: { 1996 // The only unary operator that make sense to handle here 1997 // is Deref. All others don't resolve to a "name." This includes 1998 // handling all sorts of rvalues passed to a unary operator. 1999 UnaryOperator *U = cast<UnaryOperator>(E); 2000 2001 if (U->getOpcode() == UO_Deref) 2002 return EvalAddr(U->getSubExpr()); 2003 2004 return NULL; 2005 } 2006 2007 case Stmt::ArraySubscriptExprClass: { 2008 // Array subscripts are potential references to data on the stack. We 2009 // retrieve the DeclRefExpr* for the array variable if it indeed 2010 // has local storage. 2011 return EvalAddr(cast<ArraySubscriptExpr>(E)->getBase()); 2012 } 2013 2014 case Stmt::ConditionalOperatorClass: { 2015 // For conditional operators we need to see if either the LHS or RHS are 2016 // non-NULL DeclRefExpr's. If one is non-NULL, we return it. 2017 ConditionalOperator *C = cast<ConditionalOperator>(E); 2018 2019 // Handle the GNU extension for missing LHS. 2020 if (Expr *lhsExpr = C->getLHS()) 2021 if (DeclRefExpr *LHS = EvalVal(lhsExpr)) 2022 return LHS; 2023 2024 return EvalVal(C->getRHS()); 2025 } 2026 2027 // Accesses to members are potential references to data on the stack. 2028 case Stmt::MemberExprClass: { 2029 MemberExpr *M = cast<MemberExpr>(E); 2030 2031 // Check for indirect access. We only want direct field accesses. 2032 if (!M->isArrow()) 2033 return EvalVal(M->getBase()); 2034 else 2035 return NULL; 2036 } 2037 2038 // Everything else: we simply don't reason about them. 2039 default: 2040 return NULL; 2041 } 2042} while (true); 2043} 2044 2045//===--- CHECK: Floating-Point comparisons (-Wfloat-equal) ---------------===// 2046 2047/// Check for comparisons of floating point operands using != and ==. 2048/// Issue a warning if these are no self-comparisons, as they are not likely 2049/// to do what the programmer intended. 2050void Sema::CheckFloatComparison(SourceLocation loc, Expr* lex, Expr *rex) { 2051 bool EmitWarning = true; 2052 2053 Expr* LeftExprSansParen = lex->IgnoreParens(); 2054 Expr* RightExprSansParen = rex->IgnoreParens(); 2055 2056 // Special case: check for x == x (which is OK). 2057 // Do not emit warnings for such cases. 2058 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(LeftExprSansParen)) 2059 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(RightExprSansParen)) 2060 if (DRL->getDecl() == DRR->getDecl()) 2061 EmitWarning = false; 2062 2063 2064 // Special case: check for comparisons against literals that can be exactly 2065 // represented by APFloat. In such cases, do not emit a warning. This 2066 // is a heuristic: often comparison against such literals are used to 2067 // detect if a value in a variable has not changed. This clearly can 2068 // lead to false negatives. 2069 if (EmitWarning) { 2070 if (FloatingLiteral* FLL = dyn_cast<FloatingLiteral>(LeftExprSansParen)) { 2071 if (FLL->isExact()) 2072 EmitWarning = false; 2073 } else 2074 if (FloatingLiteral* FLR = dyn_cast<FloatingLiteral>(RightExprSansParen)){ 2075 if (FLR->isExact()) 2076 EmitWarning = false; 2077 } 2078 } 2079 2080 // Check for comparisons with builtin types. 2081 if (EmitWarning) 2082 if (CallExpr* CL = dyn_cast<CallExpr>(LeftExprSansParen)) 2083 if (CL->isBuiltinCall(Context)) 2084 EmitWarning = false; 2085 2086 if (EmitWarning) 2087 if (CallExpr* CR = dyn_cast<CallExpr>(RightExprSansParen)) 2088 if (CR->isBuiltinCall(Context)) 2089 EmitWarning = false; 2090 2091 // Emit the diagnostic. 2092 if (EmitWarning) 2093 Diag(loc, diag::warn_floatingpoint_eq) 2094 << lex->getSourceRange() << rex->getSourceRange(); 2095} 2096 2097//===--- CHECK: Integer mixed-sign comparisons (-Wsign-compare) --------===// 2098//===--- CHECK: Lossy implicit conversions (-Wconversion) --------------===// 2099 2100namespace { 2101 2102/// Structure recording the 'active' range of an integer-valued 2103/// expression. 2104struct IntRange { 2105 /// The number of bits active in the int. 2106 unsigned Width; 2107 2108 /// True if the int is known not to have negative values. 2109 bool NonNegative; 2110 2111 IntRange(unsigned Width, bool NonNegative) 2112 : Width(Width), NonNegative(NonNegative) 2113 {} 2114 2115 // Returns the range of the bool type. 2116 static IntRange forBoolType() { 2117 return IntRange(1, true); 2118 } 2119 2120 // Returns the range of an integral type. 2121 static IntRange forType(ASTContext &C, QualType T) { 2122 return forCanonicalType(C, T->getCanonicalTypeInternal().getTypePtr()); 2123 } 2124 2125 // Returns the range of an integeral type based on its canonical 2126 // representation. 2127 static IntRange forCanonicalType(ASTContext &C, const Type *T) { 2128 assert(T->isCanonicalUnqualified()); 2129 2130 if (const VectorType *VT = dyn_cast<VectorType>(T)) 2131 T = VT->getElementType().getTypePtr(); 2132 if (const ComplexType *CT = dyn_cast<ComplexType>(T)) 2133 T = CT->getElementType().getTypePtr(); 2134 2135 if (const EnumType *ET = dyn_cast<EnumType>(T)) { 2136 EnumDecl *Enum = ET->getDecl(); 2137 unsigned NumPositive = Enum->getNumPositiveBits(); 2138 unsigned NumNegative = Enum->getNumNegativeBits(); 2139 2140 return IntRange(std::max(NumPositive, NumNegative), NumNegative == 0); 2141 } 2142 2143 const BuiltinType *BT = cast<BuiltinType>(T); 2144 assert(BT->isInteger()); 2145 2146 return IntRange(C.getIntWidth(QualType(T, 0)), BT->isUnsignedInteger()); 2147 } 2148 2149 // Returns the supremum of two ranges: i.e. their conservative merge. 2150 static IntRange join(IntRange L, IntRange R) { 2151 return IntRange(std::max(L.Width, R.Width), 2152 L.NonNegative && R.NonNegative); 2153 } 2154 2155 // Returns the infinum of two ranges: i.e. their aggressive merge. 2156 static IntRange meet(IntRange L, IntRange R) { 2157 return IntRange(std::min(L.Width, R.Width), 2158 L.NonNegative || R.NonNegative); 2159 } 2160}; 2161 2162IntRange GetValueRange(ASTContext &C, llvm::APSInt &value, unsigned MaxWidth) { 2163 if (value.isSigned() && value.isNegative()) 2164 return IntRange(value.getMinSignedBits(), false); 2165 2166 if (value.getBitWidth() > MaxWidth) 2167 value.trunc(MaxWidth); 2168 2169 // isNonNegative() just checks the sign bit without considering 2170 // signedness. 2171 return IntRange(value.getActiveBits(), true); 2172} 2173 2174IntRange GetValueRange(ASTContext &C, APValue &result, QualType Ty, 2175 unsigned MaxWidth) { 2176 if (result.isInt()) 2177 return GetValueRange(C, result.getInt(), MaxWidth); 2178 2179 if (result.isVector()) { 2180 IntRange R = GetValueRange(C, result.getVectorElt(0), Ty, MaxWidth); 2181 for (unsigned i = 1, e = result.getVectorLength(); i != e; ++i) { 2182 IntRange El = GetValueRange(C, result.getVectorElt(i), Ty, MaxWidth); 2183 R = IntRange::join(R, El); 2184 } 2185 return R; 2186 } 2187 2188 if (result.isComplexInt()) { 2189 IntRange R = GetValueRange(C, result.getComplexIntReal(), MaxWidth); 2190 IntRange I = GetValueRange(C, result.getComplexIntImag(), MaxWidth); 2191 return IntRange::join(R, I); 2192 } 2193 2194 // This can happen with lossless casts to intptr_t of "based" lvalues. 2195 // Assume it might use arbitrary bits. 2196 // FIXME: The only reason we need to pass the type in here is to get 2197 // the sign right on this one case. It would be nice if APValue 2198 // preserved this. 2199 assert(result.isLValue()); 2200 return IntRange(MaxWidth, Ty->isUnsignedIntegerType()); 2201} 2202 2203/// Pseudo-evaluate the given integer expression, estimating the 2204/// range of values it might take. 2205/// 2206/// \param MaxWidth - the width to which the value will be truncated 2207IntRange GetExprRange(ASTContext &C, Expr *E, unsigned MaxWidth) { 2208 E = E->IgnoreParens(); 2209 2210 // Try a full evaluation first. 2211 Expr::EvalResult result; 2212 if (E->Evaluate(result, C)) 2213 return GetValueRange(C, result.Val, E->getType(), MaxWidth); 2214 2215 // I think we only want to look through implicit casts here; if the 2216 // user has an explicit widening cast, we should treat the value as 2217 // being of the new, wider type. 2218 if (ImplicitCastExpr *CE = dyn_cast<ImplicitCastExpr>(E)) { 2219 if (CE->getCastKind() == CK_NoOp) 2220 return GetExprRange(C, CE->getSubExpr(), MaxWidth); 2221 2222 IntRange OutputTypeRange = IntRange::forType(C, CE->getType()); 2223 2224 bool isIntegerCast = (CE->getCastKind() == CK_IntegralCast); 2225 if (!isIntegerCast && CE->getCastKind() == CK_Unknown) 2226 isIntegerCast = CE->getSubExpr()->getType()->isIntegerType(); 2227 2228 // Assume that non-integer casts can span the full range of the type. 2229 if (!isIntegerCast) 2230 return OutputTypeRange; 2231 2232 IntRange SubRange 2233 = GetExprRange(C, CE->getSubExpr(), 2234 std::min(MaxWidth, OutputTypeRange.Width)); 2235 2236 // Bail out if the subexpr's range is as wide as the cast type. 2237 if (SubRange.Width >= OutputTypeRange.Width) 2238 return OutputTypeRange; 2239 2240 // Otherwise, we take the smaller width, and we're non-negative if 2241 // either the output type or the subexpr is. 2242 return IntRange(SubRange.Width, 2243 SubRange.NonNegative || OutputTypeRange.NonNegative); 2244 } 2245 2246 if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) { 2247 // If we can fold the condition, just take that operand. 2248 bool CondResult; 2249 if (CO->getCond()->EvaluateAsBooleanCondition(CondResult, C)) 2250 return GetExprRange(C, CondResult ? CO->getTrueExpr() 2251 : CO->getFalseExpr(), 2252 MaxWidth); 2253 2254 // Otherwise, conservatively merge. 2255 IntRange L = GetExprRange(C, CO->getTrueExpr(), MaxWidth); 2256 IntRange R = GetExprRange(C, CO->getFalseExpr(), MaxWidth); 2257 return IntRange::join(L, R); 2258 } 2259 2260 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) { 2261 switch (BO->getOpcode()) { 2262 2263 // Boolean-valued operations are single-bit and positive. 2264 case BO_LAnd: 2265 case BO_LOr: 2266 case BO_LT: 2267 case BO_GT: 2268 case BO_LE: 2269 case BO_GE: 2270 case BO_EQ: 2271 case BO_NE: 2272 return IntRange::forBoolType(); 2273 2274 // The type of these compound assignments is the type of the LHS, 2275 // so the RHS is not necessarily an integer. 2276 case BO_MulAssign: 2277 case BO_DivAssign: 2278 case BO_RemAssign: 2279 case BO_AddAssign: 2280 case BO_SubAssign: 2281 return IntRange::forType(C, E->getType()); 2282 2283 // Operations with opaque sources are black-listed. 2284 case BO_PtrMemD: 2285 case BO_PtrMemI: 2286 return IntRange::forType(C, E->getType()); 2287 2288 // Bitwise-and uses the *infinum* of the two source ranges. 2289 case BO_And: 2290 case BO_AndAssign: 2291 return IntRange::meet(GetExprRange(C, BO->getLHS(), MaxWidth), 2292 GetExprRange(C, BO->getRHS(), MaxWidth)); 2293 2294 // Left shift gets black-listed based on a judgement call. 2295 case BO_Shl: 2296 // ...except that we want to treat '1 << (blah)' as logically 2297 // positive. It's an important idiom. 2298 if (IntegerLiteral *I 2299 = dyn_cast<IntegerLiteral>(BO->getLHS()->IgnoreParenCasts())) { 2300 if (I->getValue() == 1) { 2301 IntRange R = IntRange::forType(C, E->getType()); 2302 return IntRange(R.Width, /*NonNegative*/ true); 2303 } 2304 } 2305 // fallthrough 2306 2307 case BO_ShlAssign: 2308 return IntRange::forType(C, E->getType()); 2309 2310 // Right shift by a constant can narrow its left argument. 2311 case BO_Shr: 2312 case BO_ShrAssign: { 2313 IntRange L = GetExprRange(C, BO->getLHS(), MaxWidth); 2314 2315 // If the shift amount is a positive constant, drop the width by 2316 // that much. 2317 llvm::APSInt shift; 2318 if (BO->getRHS()->isIntegerConstantExpr(shift, C) && 2319 shift.isNonNegative()) { 2320 unsigned zext = shift.getZExtValue(); 2321 if (zext >= L.Width) 2322 L.Width = (L.NonNegative ? 0 : 1); 2323 else 2324 L.Width -= zext; 2325 } 2326 2327 return L; 2328 } 2329 2330 // Comma acts as its right operand. 2331 case BO_Comma: 2332 return GetExprRange(C, BO->getRHS(), MaxWidth); 2333 2334 // Black-list pointer subtractions. 2335 case BO_Sub: 2336 if (BO->getLHS()->getType()->isPointerType()) 2337 return IntRange::forType(C, E->getType()); 2338 // fallthrough 2339 2340 default: 2341 break; 2342 } 2343 2344 // Treat every other operator as if it were closed on the 2345 // narrowest type that encompasses both operands. 2346 IntRange L = GetExprRange(C, BO->getLHS(), MaxWidth); 2347 IntRange R = GetExprRange(C, BO->getRHS(), MaxWidth); 2348 return IntRange::join(L, R); 2349 } 2350 2351 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) { 2352 switch (UO->getOpcode()) { 2353 // Boolean-valued operations are white-listed. 2354 case UO_LNot: 2355 return IntRange::forBoolType(); 2356 2357 // Operations with opaque sources are black-listed. 2358 case UO_Deref: 2359 case UO_AddrOf: // should be impossible 2360 return IntRange::forType(C, E->getType()); 2361 2362 default: 2363 return GetExprRange(C, UO->getSubExpr(), MaxWidth); 2364 } 2365 } 2366 2367 if (dyn_cast<OffsetOfExpr>(E)) { 2368 IntRange::forType(C, E->getType()); 2369 } 2370 2371 FieldDecl *BitField = E->getBitField(); 2372 if (BitField) { 2373 llvm::APSInt BitWidthAP = BitField->getBitWidth()->EvaluateAsInt(C); 2374 unsigned BitWidth = BitWidthAP.getZExtValue(); 2375 2376 return IntRange(BitWidth, BitField->getType()->isUnsignedIntegerType()); 2377 } 2378 2379 return IntRange::forType(C, E->getType()); 2380} 2381 2382IntRange GetExprRange(ASTContext &C, Expr *E) { 2383 return GetExprRange(C, E, C.getIntWidth(E->getType())); 2384} 2385 2386/// Checks whether the given value, which currently has the given 2387/// source semantics, has the same value when coerced through the 2388/// target semantics. 2389bool IsSameFloatAfterCast(const llvm::APFloat &value, 2390 const llvm::fltSemantics &Src, 2391 const llvm::fltSemantics &Tgt) { 2392 llvm::APFloat truncated = value; 2393 2394 bool ignored; 2395 truncated.convert(Src, llvm::APFloat::rmNearestTiesToEven, &ignored); 2396 truncated.convert(Tgt, llvm::APFloat::rmNearestTiesToEven, &ignored); 2397 2398 return truncated.bitwiseIsEqual(value); 2399} 2400 2401/// Checks whether the given value, which currently has the given 2402/// source semantics, has the same value when coerced through the 2403/// target semantics. 2404/// 2405/// The value might be a vector of floats (or a complex number). 2406bool IsSameFloatAfterCast(const APValue &value, 2407 const llvm::fltSemantics &Src, 2408 const llvm::fltSemantics &Tgt) { 2409 if (value.isFloat()) 2410 return IsSameFloatAfterCast(value.getFloat(), Src, Tgt); 2411 2412 if (value.isVector()) { 2413 for (unsigned i = 0, e = value.getVectorLength(); i != e; ++i) 2414 if (!IsSameFloatAfterCast(value.getVectorElt(i), Src, Tgt)) 2415 return false; 2416 return true; 2417 } 2418 2419 assert(value.isComplexFloat()); 2420 return (IsSameFloatAfterCast(value.getComplexFloatReal(), Src, Tgt) && 2421 IsSameFloatAfterCast(value.getComplexFloatImag(), Src, Tgt)); 2422} 2423 2424void AnalyzeImplicitConversions(Sema &S, Expr *E); 2425 2426bool IsZero(Sema &S, Expr *E) { 2427 llvm::APSInt Value; 2428 return E->isIntegerConstantExpr(Value, S.Context) && Value == 0; 2429} 2430 2431void CheckTrivialUnsignedComparison(Sema &S, BinaryOperator *E) { 2432 BinaryOperatorKind op = E->getOpcode(); 2433 if (op == BO_LT && IsZero(S, E->getRHS())) { 2434 S.Diag(E->getOperatorLoc(), diag::warn_lunsigned_always_true_comparison) 2435 << "< 0" << "false" 2436 << E->getLHS()->getSourceRange() << E->getRHS()->getSourceRange(); 2437 } else if (op == BO_GE && IsZero(S, E->getRHS())) { 2438 S.Diag(E->getOperatorLoc(), diag::warn_lunsigned_always_true_comparison) 2439 << ">= 0" << "true" 2440 << E->getLHS()->getSourceRange() << E->getRHS()->getSourceRange(); 2441 } else if (op == BO_GT && IsZero(S, E->getLHS())) { 2442 S.Diag(E->getOperatorLoc(), diag::warn_runsigned_always_true_comparison) 2443 << "0 >" << "false" 2444 << E->getLHS()->getSourceRange() << E->getRHS()->getSourceRange(); 2445 } else if (op == BO_LE && IsZero(S, E->getLHS())) { 2446 S.Diag(E->getOperatorLoc(), diag::warn_runsigned_always_true_comparison) 2447 << "0 <=" << "true" 2448 << E->getLHS()->getSourceRange() << E->getRHS()->getSourceRange(); 2449 } 2450} 2451 2452/// Analyze the operands of the given comparison. Implements the 2453/// fallback case from AnalyzeComparison. 2454void AnalyzeImpConvsInComparison(Sema &S, BinaryOperator *E) { 2455 AnalyzeImplicitConversions(S, E->getLHS()); 2456 AnalyzeImplicitConversions(S, E->getRHS()); 2457} 2458 2459/// \brief Implements -Wsign-compare. 2460/// 2461/// \param lex the left-hand expression 2462/// \param rex the right-hand expression 2463/// \param OpLoc the location of the joining operator 2464/// \param BinOpc binary opcode or 0 2465void AnalyzeComparison(Sema &S, BinaryOperator *E) { 2466 // The type the comparison is being performed in. 2467 QualType T = E->getLHS()->getType(); 2468 assert(S.Context.hasSameUnqualifiedType(T, E->getRHS()->getType()) 2469 && "comparison with mismatched types"); 2470 2471 // We don't do anything special if this isn't an unsigned integral 2472 // comparison: we're only interested in integral comparisons, and 2473 // signed comparisons only happen in cases we don't care to warn about. 2474 if (!T->hasUnsignedIntegerRepresentation()) 2475 return AnalyzeImpConvsInComparison(S, E); 2476 2477 Expr *lex = E->getLHS()->IgnoreParenImpCasts(); 2478 Expr *rex = E->getRHS()->IgnoreParenImpCasts(); 2479 2480 // Check to see if one of the (unmodified) operands is of different 2481 // signedness. 2482 Expr *signedOperand, *unsignedOperand; 2483 if (lex->getType()->hasSignedIntegerRepresentation()) { 2484 assert(!rex->getType()->hasSignedIntegerRepresentation() && 2485 "unsigned comparison between two signed integer expressions?"); 2486 signedOperand = lex; 2487 unsignedOperand = rex; 2488 } else if (rex->getType()->hasSignedIntegerRepresentation()) { 2489 signedOperand = rex; 2490 unsignedOperand = lex; 2491 } else { 2492 CheckTrivialUnsignedComparison(S, E); 2493 return AnalyzeImpConvsInComparison(S, E); 2494 } 2495 2496 // Otherwise, calculate the effective range of the signed operand. 2497 IntRange signedRange = GetExprRange(S.Context, signedOperand); 2498 2499 // Go ahead and analyze implicit conversions in the operands. Note 2500 // that we skip the implicit conversions on both sides. 2501 AnalyzeImplicitConversions(S, lex); 2502 AnalyzeImplicitConversions(S, rex); 2503 2504 // If the signed range is non-negative, -Wsign-compare won't fire, 2505 // but we should still check for comparisons which are always true 2506 // or false. 2507 if (signedRange.NonNegative) 2508 return CheckTrivialUnsignedComparison(S, E); 2509 2510 // For (in)equality comparisons, if the unsigned operand is a 2511 // constant which cannot collide with a overflowed signed operand, 2512 // then reinterpreting the signed operand as unsigned will not 2513 // change the result of the comparison. 2514 if (E->isEqualityOp()) { 2515 unsigned comparisonWidth = S.Context.getIntWidth(T); 2516 IntRange unsignedRange = GetExprRange(S.Context, unsignedOperand); 2517 2518 // We should never be unable to prove that the unsigned operand is 2519 // non-negative. 2520 assert(unsignedRange.NonNegative && "unsigned range includes negative?"); 2521 2522 if (unsignedRange.Width < comparisonWidth) 2523 return; 2524 } 2525 2526 S.Diag(E->getOperatorLoc(), diag::warn_mixed_sign_comparison) 2527 << lex->getType() << rex->getType() 2528 << lex->getSourceRange() << rex->getSourceRange(); 2529} 2530 2531/// Diagnose an implicit cast; purely a helper for CheckImplicitConversion. 2532void DiagnoseImpCast(Sema &S, Expr *E, QualType T, unsigned diag) { 2533 S.Diag(E->getExprLoc(), diag) << E->getType() << T << E->getSourceRange(); 2534} 2535 2536void CheckImplicitConversion(Sema &S, Expr *E, QualType T, 2537 bool *ICContext = 0) { 2538 if (E->isTypeDependent() || E->isValueDependent()) return; 2539 2540 const Type *Source = S.Context.getCanonicalType(E->getType()).getTypePtr(); 2541 const Type *Target = S.Context.getCanonicalType(T).getTypePtr(); 2542 if (Source == Target) return; 2543 if (Target->isDependentType()) return; 2544 2545 // Never diagnose implicit casts to bool. 2546 if (Target->isSpecificBuiltinType(BuiltinType::Bool)) 2547 return; 2548 2549 // Strip vector types. 2550 if (isa<VectorType>(Source)) { 2551 if (!isa<VectorType>(Target)) 2552 return DiagnoseImpCast(S, E, T, diag::warn_impcast_vector_scalar); 2553 2554 Source = cast<VectorType>(Source)->getElementType().getTypePtr(); 2555 Target = cast<VectorType>(Target)->getElementType().getTypePtr(); 2556 } 2557 2558 // Strip complex types. 2559 if (isa<ComplexType>(Source)) { 2560 if (!isa<ComplexType>(Target)) 2561 return DiagnoseImpCast(S, E, T, diag::warn_impcast_complex_scalar); 2562 2563 Source = cast<ComplexType>(Source)->getElementType().getTypePtr(); 2564 Target = cast<ComplexType>(Target)->getElementType().getTypePtr(); 2565 } 2566 2567 const BuiltinType *SourceBT = dyn_cast<BuiltinType>(Source); 2568 const BuiltinType *TargetBT = dyn_cast<BuiltinType>(Target); 2569 2570 // If the source is floating point... 2571 if (SourceBT && SourceBT->isFloatingPoint()) { 2572 // ...and the target is floating point... 2573 if (TargetBT && TargetBT->isFloatingPoint()) { 2574 // ...then warn if we're dropping FP rank. 2575 2576 // Builtin FP kinds are ordered by increasing FP rank. 2577 if (SourceBT->getKind() > TargetBT->getKind()) { 2578 // Don't warn about float constants that are precisely 2579 // representable in the target type. 2580 Expr::EvalResult result; 2581 if (E->Evaluate(result, S.Context)) { 2582 // Value might be a float, a float vector, or a float complex. 2583 if (IsSameFloatAfterCast(result.Val, 2584 S.Context.getFloatTypeSemantics(QualType(TargetBT, 0)), 2585 S.Context.getFloatTypeSemantics(QualType(SourceBT, 0)))) 2586 return; 2587 } 2588 2589 DiagnoseImpCast(S, E, T, diag::warn_impcast_float_precision); 2590 } 2591 return; 2592 } 2593 2594 // If the target is integral, always warn. 2595 if ((TargetBT && TargetBT->isInteger())) 2596 // TODO: don't warn for integer values? 2597 DiagnoseImpCast(S, E, T, diag::warn_impcast_float_integer); 2598 2599 return; 2600 } 2601 2602 if (!Source->isIntegerType() || !Target->isIntegerType()) 2603 return; 2604 2605 IntRange SourceRange = GetExprRange(S.Context, E); 2606 IntRange TargetRange = IntRange::forCanonicalType(S.Context, Target); 2607 2608 if (SourceRange.Width > TargetRange.Width) { 2609 // People want to build with -Wshorten-64-to-32 and not -Wconversion 2610 // and by god we'll let them. 2611 if (SourceRange.Width == 64 && TargetRange.Width == 32) 2612 return DiagnoseImpCast(S, E, T, diag::warn_impcast_integer_64_32); 2613 return DiagnoseImpCast(S, E, T, diag::warn_impcast_integer_precision); 2614 } 2615 2616 if ((TargetRange.NonNegative && !SourceRange.NonNegative) || 2617 (!TargetRange.NonNegative && SourceRange.NonNegative && 2618 SourceRange.Width == TargetRange.Width)) { 2619 unsigned DiagID = diag::warn_impcast_integer_sign; 2620 2621 // Traditionally, gcc has warned about this under -Wsign-compare. 2622 // We also want to warn about it in -Wconversion. 2623 // So if -Wconversion is off, use a completely identical diagnostic 2624 // in the sign-compare group. 2625 // The conditional-checking code will 2626 if (ICContext) { 2627 DiagID = diag::warn_impcast_integer_sign_conditional; 2628 *ICContext = true; 2629 } 2630 2631 return DiagnoseImpCast(S, E, T, DiagID); 2632 } 2633 2634 return; 2635} 2636 2637void CheckConditionalOperator(Sema &S, ConditionalOperator *E, QualType T); 2638 2639void CheckConditionalOperand(Sema &S, Expr *E, QualType T, 2640 bool &ICContext) { 2641 E = E->IgnoreParenImpCasts(); 2642 2643 if (isa<ConditionalOperator>(E)) 2644 return CheckConditionalOperator(S, cast<ConditionalOperator>(E), T); 2645 2646 AnalyzeImplicitConversions(S, E); 2647 if (E->getType() != T) 2648 return CheckImplicitConversion(S, E, T, &ICContext); 2649 return; 2650} 2651 2652void CheckConditionalOperator(Sema &S, ConditionalOperator *E, QualType T) { 2653 AnalyzeImplicitConversions(S, E->getCond()); 2654 2655 bool Suspicious = false; 2656 CheckConditionalOperand(S, E->getTrueExpr(), T, Suspicious); 2657 CheckConditionalOperand(S, E->getFalseExpr(), T, Suspicious); 2658 2659 // If -Wconversion would have warned about either of the candidates 2660 // for a signedness conversion to the context type... 2661 if (!Suspicious) return; 2662 2663 // ...but it's currently ignored... 2664 if (S.Diags.getDiagnosticLevel(diag::warn_impcast_integer_sign_conditional)) 2665 return; 2666 2667 // ...and -Wsign-compare isn't... 2668 if (!S.Diags.getDiagnosticLevel(diag::warn_mixed_sign_conditional)) 2669 return; 2670 2671 // ...then check whether it would have warned about either of the 2672 // candidates for a signedness conversion to the condition type. 2673 if (E->getType() != T) { 2674 Suspicious = false; 2675 CheckImplicitConversion(S, E->getTrueExpr()->IgnoreParenImpCasts(), 2676 E->getType(), &Suspicious); 2677 if (!Suspicious) 2678 CheckImplicitConversion(S, E->getFalseExpr()->IgnoreParenImpCasts(), 2679 E->getType(), &Suspicious); 2680 if (!Suspicious) 2681 return; 2682 } 2683 2684 // If so, emit a diagnostic under -Wsign-compare. 2685 Expr *lex = E->getTrueExpr()->IgnoreParenImpCasts(); 2686 Expr *rex = E->getFalseExpr()->IgnoreParenImpCasts(); 2687 S.Diag(E->getQuestionLoc(), diag::warn_mixed_sign_conditional) 2688 << lex->getType() << rex->getType() 2689 << lex->getSourceRange() << rex->getSourceRange(); 2690} 2691 2692/// AnalyzeImplicitConversions - Find and report any interesting 2693/// implicit conversions in the given expression. There are a couple 2694/// of competing diagnostics here, -Wconversion and -Wsign-compare. 2695void AnalyzeImplicitConversions(Sema &S, Expr *OrigE) { 2696 QualType T = OrigE->getType(); 2697 Expr *E = OrigE->IgnoreParenImpCasts(); 2698 2699 // For conditional operators, we analyze the arguments as if they 2700 // were being fed directly into the output. 2701 if (isa<ConditionalOperator>(E)) { 2702 ConditionalOperator *CO = cast<ConditionalOperator>(E); 2703 CheckConditionalOperator(S, CO, T); 2704 return; 2705 } 2706 2707 // Go ahead and check any implicit conversions we might have skipped. 2708 // The non-canonical typecheck is just an optimization; 2709 // CheckImplicitConversion will filter out dead implicit conversions. 2710 if (E->getType() != T) 2711 CheckImplicitConversion(S, E, T); 2712 2713 // Now continue drilling into this expression. 2714 2715 // Skip past explicit casts. 2716 if (isa<ExplicitCastExpr>(E)) { 2717 E = cast<ExplicitCastExpr>(E)->getSubExpr()->IgnoreParenImpCasts(); 2718 return AnalyzeImplicitConversions(S, E); 2719 } 2720 2721 // Do a somewhat different check with comparison operators. 2722 if (isa<BinaryOperator>(E) && cast<BinaryOperator>(E)->isComparisonOp()) 2723 return AnalyzeComparison(S, cast<BinaryOperator>(E)); 2724 2725 // These break the otherwise-useful invariant below. Fortunately, 2726 // we don't really need to recurse into them, because any internal 2727 // expressions should have been analyzed already when they were 2728 // built into statements. 2729 if (isa<StmtExpr>(E)) return; 2730 2731 // Don't descend into unevaluated contexts. 2732 if (isa<SizeOfAlignOfExpr>(E)) return; 2733 2734 // Now just recurse over the expression's children. 2735 for (Stmt::child_iterator I = E->child_begin(), IE = E->child_end(); 2736 I != IE; ++I) 2737 AnalyzeImplicitConversions(S, cast<Expr>(*I)); 2738} 2739 2740} // end anonymous namespace 2741 2742/// Diagnoses "dangerous" implicit conversions within the given 2743/// expression (which is a full expression). Implements -Wconversion 2744/// and -Wsign-compare. 2745void Sema::CheckImplicitConversions(Expr *E) { 2746 // Don't diagnose in unevaluated contexts. 2747 if (ExprEvalContexts.back().Context == Sema::Unevaluated) 2748 return; 2749 2750 // Don't diagnose for value- or type-dependent expressions. 2751 if (E->isTypeDependent() || E->isValueDependent()) 2752 return; 2753 2754 AnalyzeImplicitConversions(*this, E); 2755} 2756 2757/// CheckParmsForFunctionDef - Check that the parameters of the given 2758/// function are appropriate for the definition of a function. This 2759/// takes care of any checks that cannot be performed on the 2760/// declaration itself, e.g., that the types of each of the function 2761/// parameters are complete. 2762bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 2763 bool HasInvalidParm = false; 2764 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2765 ParmVarDecl *Param = FD->getParamDecl(p); 2766 2767 // C99 6.7.5.3p4: the parameters in a parameter type list in a 2768 // function declarator that is part of a function definition of 2769 // that function shall not have incomplete type. 2770 // 2771 // This is also C++ [dcl.fct]p6. 2772 if (!Param->isInvalidDecl() && 2773 RequireCompleteType(Param->getLocation(), Param->getType(), 2774 diag::err_typecheck_decl_incomplete_type)) { 2775 Param->setInvalidDecl(); 2776 HasInvalidParm = true; 2777 } 2778 2779 // C99 6.9.1p5: If the declarator includes a parameter type list, the 2780 // declaration of each parameter shall include an identifier. 2781 if (Param->getIdentifier() == 0 && 2782 !Param->isImplicit() && 2783 !getLangOptions().CPlusPlus) 2784 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 2785 2786 // C99 6.7.5.3p12: 2787 // If the function declarator is not part of a definition of that 2788 // function, parameters may have incomplete type and may use the [*] 2789 // notation in their sequences of declarator specifiers to specify 2790 // variable length array types. 2791 QualType PType = Param->getOriginalType(); 2792 if (const ArrayType *AT = Context.getAsArrayType(PType)) { 2793 if (AT->getSizeModifier() == ArrayType::Star) { 2794 // FIXME: This diagnosic should point the the '[*]' if source-location 2795 // information is added for it. 2796 Diag(Param->getLocation(), diag::err_array_star_in_function_definition); 2797 } 2798 } 2799 } 2800 2801 return HasInvalidParm; 2802} 2803 2804/// CheckCastAlign - Implements -Wcast-align, which warns when a 2805/// pointer cast increases the alignment requirements. 2806void Sema::CheckCastAlign(Expr *Op, QualType T, SourceRange TRange) { 2807 // This is actually a lot of work to potentially be doing on every 2808 // cast; don't do it if we're ignoring -Wcast_align (as is the default). 2809 if (getDiagnostics().getDiagnosticLevel(diag::warn_cast_align) 2810 == Diagnostic::Ignored) 2811 return; 2812 2813 // Ignore dependent types. 2814 if (T->isDependentType() || Op->getType()->isDependentType()) 2815 return; 2816 2817 // Require that the destination be a pointer type. 2818 const PointerType *DestPtr = T->getAs<PointerType>(); 2819 if (!DestPtr) return; 2820 2821 // If the destination has alignment 1, we're done. 2822 QualType DestPointee = DestPtr->getPointeeType(); 2823 if (DestPointee->isIncompleteType()) return; 2824 CharUnits DestAlign = Context.getTypeAlignInChars(DestPointee); 2825 if (DestAlign.isOne()) return; 2826 2827 // Require that the source be a pointer type. 2828 const PointerType *SrcPtr = Op->getType()->getAs<PointerType>(); 2829 if (!SrcPtr) return; 2830 QualType SrcPointee = SrcPtr->getPointeeType(); 2831 2832 // Whitelist casts from cv void*. We already implicitly 2833 // whitelisted casts to cv void*, since they have alignment 1. 2834 // Also whitelist casts involving incomplete types, which implicitly 2835 // includes 'void'. 2836 if (SrcPointee->isIncompleteType()) return; 2837 2838 CharUnits SrcAlign = Context.getTypeAlignInChars(SrcPointee); 2839 if (SrcAlign >= DestAlign) return; 2840 2841 Diag(TRange.getBegin(), diag::warn_cast_align) 2842 << Op->getType() << T 2843 << static_cast<unsigned>(SrcAlign.getQuantity()) 2844 << static_cast<unsigned>(DestAlign.getQuantity()) 2845 << TRange << Op->getSourceRange(); 2846} 2847 2848