diff options
Diffstat (limited to 'lib/Sema/SemaChecking.cpp')
| -rw-r--r-- | lib/Sema/SemaChecking.cpp | 806 |
1 files changed, 549 insertions, 257 deletions
diff --git a/lib/Sema/SemaChecking.cpp b/lib/Sema/SemaChecking.cpp index a0b4b98..5566654 100644 --- a/lib/Sema/SemaChecking.cpp +++ b/lib/Sema/SemaChecking.cpp @@ -25,82 +25,23 @@ #include "clang/AST/DeclObjC.h" #include "clang/AST/StmtCXX.h" #include "clang/AST/StmtObjC.h" -#include "clang/Lex/LiteralSupport.h" #include "clang/Lex/Preprocessor.h" #include "llvm/ADT/BitVector.h" #include "llvm/ADT/STLExtras.h" #include "llvm/Support/raw_ostream.h" #include "clang/Basic/TargetBuiltins.h" #include "clang/Basic/TargetInfo.h" +#include "clang/Basic/ConvertUTF.h" #include <limits> using namespace clang; using namespace sema; -/// getLocationOfStringLiteralByte - Return a source location that points to the -/// specified byte of the specified string literal. -/// -/// Strings are amazingly complex. They can be formed from multiple tokens and -/// can have escape sequences in them in addition to the usual trigraph and -/// escaped newline business. This routine handles this complexity. -/// SourceLocation Sema::getLocationOfStringLiteralByte(const StringLiteral *SL, unsigned ByteNo) const { - assert(!SL->isWide() && "This doesn't work for wide strings yet"); - - // Loop over all of the tokens in this string until we find the one that - // contains the byte we're looking for. - unsigned TokNo = 0; - while (1) { - assert(TokNo < SL->getNumConcatenated() && "Invalid byte number!"); - SourceLocation StrTokLoc = SL->getStrTokenLoc(TokNo); - - // Get the spelling of the string so that we can get the data that makes up - // the string literal, not the identifier for the macro it is potentially - // expanded through. - SourceLocation StrTokSpellingLoc = SourceMgr.getSpellingLoc(StrTokLoc); - - // Re-lex the token to get its length and original spelling. - std::pair<FileID, unsigned> LocInfo = - SourceMgr.getDecomposedLoc(StrTokSpellingLoc); - bool Invalid = false; - llvm::StringRef Buffer = SourceMgr.getBufferData(LocInfo.first, &Invalid); - if (Invalid) - return StrTokSpellingLoc; - - const char *StrData = Buffer.data()+LocInfo.second; - - // Create a langops struct and enable trigraphs. This is sufficient for - // relexing tokens. - LangOptions LangOpts; - LangOpts.Trigraphs = true; - - // Create a lexer starting at the beginning of this token. - Lexer TheLexer(StrTokSpellingLoc, LangOpts, Buffer.begin(), StrData, - Buffer.end()); - Token TheTok; - TheLexer.LexFromRawLexer(TheTok); - - // Use the StringLiteralParser to compute the length of the string in bytes. - StringLiteralParser SLP(&TheTok, 1, PP, /*Complain=*/false); - unsigned TokNumBytes = SLP.GetStringLength(); - - // If the byte is in this token, return the location of the byte. - if (ByteNo < TokNumBytes || - (ByteNo == TokNumBytes && TokNo == SL->getNumConcatenated())) { - unsigned Offset = - StringLiteralParser::getOffsetOfStringByte(TheTok, ByteNo, PP, - /*Complain=*/false); - - // Now that we know the offset of the token in the spelling, use the - // preprocessor to get the offset in the original source. - return PP.AdvanceToTokenCharacter(StrTokLoc, Offset); - } - - // Move to the next string token. - ++TokNo; - ByteNo -= TokNumBytes; - } + return SL->getLocationOfByte(ByteNo, PP.getSourceManager(), + PP.getLangOptions(), PP.getTargetInfo()); } + /// CheckablePrintfAttr - does a function call have a "printf" attribute /// and arguments that merit checking? @@ -129,6 +70,24 @@ ExprResult Sema::CheckBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall) { ExprResult TheCallResult(Owned(TheCall)); + // Find out if any arguments are required to be integer constant expressions. + unsigned ICEArguments = 0; + ASTContext::GetBuiltinTypeError Error; + Context.GetBuiltinType(BuiltinID, Error, &ICEArguments); + if (Error != ASTContext::GE_None) + ICEArguments = 0; // Don't diagnose previously diagnosed errors. + + // If any arguments are required to be ICE's, check and diagnose. + for (unsigned ArgNo = 0; ICEArguments != 0; ++ArgNo) { + // Skip arguments not required to be ICE's. + if ((ICEArguments & (1 << ArgNo)) == 0) continue; + + llvm::APSInt Result; + if (SemaBuiltinConstantArg(TheCall, ArgNo, Result)) + return true; + ICEArguments &= ~(1 << ArgNo); + } + switch (BuiltinID) { case Builtin::BI__builtin___CFStringMakeConstantString: assert(TheCall->getNumArgs() == 1 && @@ -162,19 +121,6 @@ Sema::CheckBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall) { if (SemaBuiltinFPClassification(TheCall, 1)) return ExprError(); break; - case Builtin::BI__builtin_return_address: - case Builtin::BI__builtin_frame_address: { - llvm::APSInt Result; - if (SemaBuiltinConstantArg(TheCall, 0, Result)) - return ExprError(); - break; - } - case Builtin::BI__builtin_eh_return_data_regno: { - llvm::APSInt Result; - if (SemaBuiltinConstantArg(TheCall, 0, Result)) - return ExprError(); - break; - } case Builtin::BI__builtin_shufflevector: return SemaBuiltinShuffleVector(TheCall); // TheCall will be freed by the smart pointer here, but that's fine, since @@ -191,6 +137,16 @@ Sema::CheckBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall) { if (SemaBuiltinLongjmp(TheCall)) return ExprError(); break; + case Builtin::BI__builtin_constant_p: + if (TheCall->getNumArgs() == 0) + return Diag(TheCall->getLocEnd(), diag::err_typecheck_call_too_few_args) + << 0 /*function call*/ << 1 << 0 << TheCall->getSourceRange(); + if (TheCall->getNumArgs() > 1) + return Diag(TheCall->getArg(1)->getLocStart(), + diag::err_typecheck_call_too_many_args) + << 0 /*function call*/ << 1 << TheCall->getNumArgs() + << TheCall->getArg(1)->getSourceRange(); + break; case Builtin::BI__sync_fetch_and_add: case Builtin::BI__sync_fetch_and_sub: case Builtin::BI__sync_fetch_and_or: @@ -217,11 +173,6 @@ Sema::CheckBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall) { if (CheckARMBuiltinFunctionCall(BuiltinID, TheCall)) return ExprError(); break; - case llvm::Triple::x86: - case llvm::Triple::x86_64: - if (CheckX86BuiltinFunctionCall(BuiltinID, TheCall)) - return ExprError(); - break; default: break; } @@ -230,19 +181,6 @@ Sema::CheckBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall) { return move(TheCallResult); } -bool Sema::CheckX86BuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall) { - switch (BuiltinID) { - case X86::BI__builtin_ia32_palignr128: - case X86::BI__builtin_ia32_palignr: { - llvm::APSInt Result; - if (SemaBuiltinConstantArg(TheCall, 2, Result)) - return true; - break; - } - } - return false; -} - // Get the valid immediate range for the specified NEON type code. static unsigned RFT(unsigned t, bool shift = false) { bool quad = t & 0x10; @@ -260,11 +198,9 @@ static unsigned RFT(unsigned t, bool shift = false) { assert(!shift && "cannot shift float types!"); return (2 << (int)quad) - 1; case 5: // poly8 - assert(!shift && "cannot shift polynomial types!"); - return (8 << (int)quad) - 1; + return shift ? 7 : (8 << (int)quad) - 1; case 6: // poly16 - assert(!shift && "cannot shift polynomial types!"); - return (4 << (int)quad) - 1; + return shift ? 15 : (4 << (int)quad) - 1; case 7: // float16 assert(!shift && "cannot shift float types!"); return (4 << (int)quad) - 1; @@ -339,8 +275,12 @@ bool Sema::CheckFunctionCall(FunctionDecl *FDecl, CallExpr *TheCall) { // more efficient. For example, just map function ids to custom // handlers. - // Printf checking. - if (const FormatAttr *Format = FDecl->getAttr<FormatAttr>()) { + // Printf and scanf checking. + for (specific_attr_iterator<FormatAttr> + i = FDecl->specific_attr_begin<FormatAttr>(), + e = FDecl->specific_attr_end<FormatAttr>(); i != e ; ++i) { + + const FormatAttr *Format = *i; const bool b = Format->getType() == "scanf"; if (b || CheckablePrintfAttr(Format, TheCall)) { bool HasVAListArg = Format->getFirstArg() == 0; @@ -351,12 +291,11 @@ bool Sema::CheckFunctionCall(FunctionDecl *FDecl, CallExpr *TheCall) { } } - specific_attr_iterator<NonNullAttr> - i = FDecl->specific_attr_begin<NonNullAttr>(), - e = FDecl->specific_attr_end<NonNullAttr>(); - - for (; i != e; ++i) + for (specific_attr_iterator<NonNullAttr> + i = FDecl->specific_attr_begin<NonNullAttr>(), + e = FDecl->specific_attr_end<NonNullAttr>(); i != e; ++i) { CheckNonNullArguments(*i, TheCall); + } return false; } @@ -422,7 +361,7 @@ Sema::SemaBuiltinAtomicOverloaded(ExprResult TheCallResult) { QualType ValType = FirstArg->getType()->getAs<PointerType>()->getPointeeType(); - if (!ValType->isIntegerType() && !ValType->isPointerType() && + if (!ValType->isIntegerType() && !ValType->isAnyPointerType() && !ValType->isBlockPointerType()) { Diag(DRE->getLocStart(), diag::err_atomic_builtin_must_be_pointer_intptr) << FirstArg->getType() << FirstArg->getSourceRange(); @@ -545,9 +484,10 @@ Sema::SemaBuiltinAtomicOverloaded(ExprResult TheCallResult) { // GCC does an implicit conversion to the pointer or integer ValType. This // can fail in some cases (1i -> int**), check for this error case now. - CastKind Kind = CK_Unknown; + CastKind Kind = CK_Invalid; + ExprValueKind VK = VK_RValue; CXXCastPath BasePath; - if (CheckCastTypes(Arg->getSourceRange(), ValType, Arg, Kind, BasePath)) + if (CheckCastTypes(Arg->getSourceRange(), ValType, Arg, Kind, VK, BasePath)) return ExprError(); // Okay, we have something that *can* be converted to the right type. Check @@ -556,7 +496,7 @@ Sema::SemaBuiltinAtomicOverloaded(ExprResult TheCallResult) { // pass in 42. The 42 gets converted to char. This is even more strange // for things like 45.123 -> char, etc. // FIXME: Do this check. - ImpCastExprToType(Arg, ValType, Kind, VK_RValue, &BasePath); + ImpCastExprToType(Arg, ValType, Kind, VK, &BasePath); TheCall->setArg(i+1, Arg); } @@ -581,9 +521,6 @@ Sema::SemaBuiltinAtomicOverloaded(ExprResult TheCallResult) { /// CheckObjCString - Checks that the argument to the builtin /// CFString constructor is correct -/// FIXME: GCC currently emits the following warning: -/// "warning: input conversion stopped due to an input byte that does not -/// belong to the input codeset UTF-8" /// Note: It might also make sense to do the UTF-16 conversion here (would /// simplify the backend). bool Sema::CheckObjCString(Expr *Arg) { @@ -602,7 +539,21 @@ bool Sema::CheckObjCString(Expr *Arg) { diag::warn_cfstring_literal_contains_nul_character) << Arg->getSourceRange(); } - + if (Literal->containsNonAsciiOrNull()) { + llvm::StringRef String = Literal->getString(); + unsigned NumBytes = String.size(); + llvm::SmallVector<UTF16, 128> ToBuf(NumBytes); + const UTF8 *FromPtr = (UTF8 *)String.data(); + UTF16 *ToPtr = &ToBuf[0]; + + ConversionResult Result = ConvertUTF8toUTF16(&FromPtr, FromPtr + NumBytes, + &ToPtr, ToPtr + NumBytes, + strictConversion); + // Check for conversion failure. + if (Result != conversionOK) + Diag(Arg->getLocStart(), + diag::warn_cfstring_truncated) << Arg->getSourceRange(); + } return false; } @@ -798,7 +749,7 @@ ExprResult Sema::SemaBuiltinShuffleVector(CallExpr *TheCall) { } else if (numElements != numResElements) { QualType eltType = LHSType->getAs<VectorType>()->getElementType(); resType = Context.getVectorType(eltType, numResElements, - VectorType::NotAltiVec); + VectorType::GenericVector); } } @@ -929,31 +880,44 @@ bool Sema::SemaCheckStringLiteral(const Expr *E, const CallExpr *TheCall, bool HasVAListArg, unsigned format_idx, unsigned firstDataArg, bool isPrintf) { - + tryAgain: if (E->isTypeDependent() || E->isValueDependent()) return false; switch (E->getStmtClass()) { + case Stmt::BinaryConditionalOperatorClass: case Stmt::ConditionalOperatorClass: { - const ConditionalOperator *C = cast<ConditionalOperator>(E); + const AbstractConditionalOperator *C = cast<AbstractConditionalOperator>(E); return SemaCheckStringLiteral(C->getTrueExpr(), TheCall, HasVAListArg, format_idx, firstDataArg, isPrintf) - && SemaCheckStringLiteral(C->getRHS(), TheCall, HasVAListArg, + && SemaCheckStringLiteral(C->getFalseExpr(), TheCall, HasVAListArg, format_idx, firstDataArg, isPrintf); } + case Stmt::IntegerLiteralClass: + // Technically -Wformat-nonliteral does not warn about this case. + // The behavior of printf and friends in this case is implementation + // dependent. Ideally if the format string cannot be null then + // it should have a 'nonnull' attribute in the function prototype. + return true; + case Stmt::ImplicitCastExprClass: { - const ImplicitCastExpr *Expr = cast<ImplicitCastExpr>(E); - return SemaCheckStringLiteral(Expr->getSubExpr(), TheCall, HasVAListArg, - format_idx, firstDataArg, isPrintf); + E = cast<ImplicitCastExpr>(E)->getSubExpr(); + goto tryAgain; } case Stmt::ParenExprClass: { - const ParenExpr *Expr = cast<ParenExpr>(E); - return SemaCheckStringLiteral(Expr->getSubExpr(), TheCall, HasVAListArg, - format_idx, firstDataArg, isPrintf); + E = cast<ParenExpr>(E)->getSubExpr(); + goto tryAgain; } + case Stmt::OpaqueValueExprClass: + if (const Expr *src = cast<OpaqueValueExpr>(E)->getSourceExpr()) { + E = src; + goto tryAgain; + } + return false; + case Stmt::DeclRefExprClass: { const DeclRefExpr *DR = cast<DeclRefExpr>(E); @@ -1072,12 +1036,16 @@ Sema::CheckPrintfScanfArguments(const CallExpr *TheCall, bool HasVAListArg, // of member functions is counted. However, it doesn't appear in our own // lists, so decrement format_idx in that case. if (isa<CXXMemberCallExpr>(TheCall)) { - // Catch a format attribute mistakenly referring to the object argument. - if (format_idx == 0) - return; - --format_idx; - if(firstDataArg != 0) - --firstDataArg; + const CXXMethodDecl *method_decl = + dyn_cast<CXXMethodDecl>(TheCall->getCalleeDecl()); + if (method_decl && method_decl->isInstance()) { + // Catch a format attribute mistakenly referring to the object argument. + if (format_idx == 0) + return; + --format_idx; + if(firstDataArg != 0) + --firstDataArg; + } } // CHECK: printf/scanf-like function is called with no format string. @@ -1531,6 +1499,8 @@ CheckPrintfHandler::HandlePrintfSpecifier(const analyze_printf::PrintfSpecifier } // Check each flag does not conflict with any other component. + if (!FS.hasValidThousandsGroupingPrefix()) + HandleFlag(FS, FS.hasThousandsGrouping(), startSpecifier, specifierLen); if (!FS.hasValidLeadingZeros()) HandleFlag(FS, FS.hasLeadingZeros(), startSpecifier, specifierLen); if (!FS.hasValidPlusPrefix()) @@ -1585,9 +1555,12 @@ CheckPrintfHandler::HandlePrintfSpecifier(const analyze_printf::PrintfSpecifier // or 'short' to an 'int'. This is done because printf is a varargs // function. if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(Ex)) - if (ICE->getType() == S.Context.IntTy) - if (ATR.matchesType(S.Context, ICE->getSubExpr()->getType())) + if (ICE->getType() == S.Context.IntTy) { + // All further checking is done on the subexpression. + Ex = ICE->getSubExpr(); + if (ATR.matchesType(S.Context, Ex->getType())) return true; + } // We may be able to offer a FixItHint if it is a supported type. PrintfSpecifier fixedFS = FS; @@ -1794,8 +1767,8 @@ void Sema::CheckFormatString(const StringLiteral *FExpr, //===--- CHECK: Return Address of Stack Variable --------------------------===// -static DeclRefExpr* EvalVal(Expr *E); -static DeclRefExpr* EvalAddr(Expr* E); +static Expr *EvalVal(Expr *E, llvm::SmallVectorImpl<DeclRefExpr *> &refVars); +static Expr *EvalAddr(Expr* E, llvm::SmallVectorImpl<DeclRefExpr *> &refVars); /// CheckReturnStackAddr - Check if a return statement returns the address /// of a stack variable. @@ -1803,45 +1776,79 @@ void Sema::CheckReturnStackAddr(Expr *RetValExp, QualType lhsType, SourceLocation ReturnLoc) { - // Perform checking for returned stack addresses. - if (lhsType->isPointerType() || lhsType->isBlockPointerType()) { - if (DeclRefExpr *DR = EvalAddr(RetValExp)) - Diag(DR->getLocStart(), diag::warn_ret_stack_addr) - << DR->getDecl()->getDeclName() << RetValExp->getSourceRange(); - - // Skip over implicit cast expressions when checking for block expressions. - RetValExp = RetValExp->IgnoreParenCasts(); + Expr *stackE = 0; + llvm::SmallVector<DeclRefExpr *, 8> refVars; - if (BlockExpr *C = dyn_cast<BlockExpr>(RetValExp)) - if (C->hasBlockDeclRefExprs()) - Diag(C->getLocStart(), diag::err_ret_local_block) - << C->getSourceRange(); + // Perform checking for returned stack addresses, local blocks, + // label addresses or references to temporaries. + if (lhsType->isPointerType() || lhsType->isBlockPointerType()) { + stackE = EvalAddr(RetValExp, refVars); + } else if (lhsType->isReferenceType()) { + stackE = EvalVal(RetValExp, refVars); + } - if (AddrLabelExpr *ALE = dyn_cast<AddrLabelExpr>(RetValExp)) - Diag(ALE->getLocStart(), diag::warn_ret_addr_label) - << ALE->getSourceRange(); + if (stackE == 0) + return; // Nothing suspicious was found. - } else if (lhsType->isReferenceType()) { - // Perform checking for stack values returned by reference. - // Check for a reference to the stack - if (DeclRefExpr *DR = EvalVal(RetValExp)) - Diag(DR->getLocStart(), diag::warn_ret_stack_ref) - << DR->getDecl()->getDeclName() << RetValExp->getSourceRange(); + SourceLocation diagLoc; + SourceRange diagRange; + if (refVars.empty()) { + diagLoc = stackE->getLocStart(); + diagRange = stackE->getSourceRange(); + } else { + // We followed through a reference variable. 'stackE' contains the + // problematic expression but we will warn at the return statement pointing + // at the reference variable. We will later display the "trail" of + // reference variables using notes. + diagLoc = refVars[0]->getLocStart(); + diagRange = refVars[0]->getSourceRange(); + } + + if (DeclRefExpr *DR = dyn_cast<DeclRefExpr>(stackE)) { //address of local var. + Diag(diagLoc, lhsType->isReferenceType() ? diag::warn_ret_stack_ref + : diag::warn_ret_stack_addr) + << DR->getDecl()->getDeclName() << diagRange; + } else if (isa<BlockExpr>(stackE)) { // local block. + Diag(diagLoc, diag::err_ret_local_block) << diagRange; + } else if (isa<AddrLabelExpr>(stackE)) { // address of label. + Diag(diagLoc, diag::warn_ret_addr_label) << diagRange; + } else { // local temporary. + Diag(diagLoc, lhsType->isReferenceType() ? diag::warn_ret_local_temp_ref + : diag::warn_ret_local_temp_addr) + << diagRange; + } + + // Display the "trail" of reference variables that we followed until we + // found the problematic expression using notes. + for (unsigned i = 0, e = refVars.size(); i != e; ++i) { + VarDecl *VD = cast<VarDecl>(refVars[i]->getDecl()); + // If this var binds to another reference var, show the range of the next + // var, otherwise the var binds to the problematic expression, in which case + // show the range of the expression. + SourceRange range = (i < e-1) ? refVars[i+1]->getSourceRange() + : stackE->getSourceRange(); + Diag(VD->getLocation(), diag::note_ref_var_local_bind) + << VD->getDeclName() << range; } } /// EvalAddr - EvalAddr and EvalVal are mutually recursive functions that /// check if the expression in a return statement evaluates to an address -/// to a location on the stack. The recursion is used to traverse the +/// to a location on the stack, a local block, an address of a label, or a +/// reference to local temporary. The recursion is used to traverse the /// AST of the return expression, with recursion backtracking when we -/// encounter a subexpression that (1) clearly does not lead to the address -/// of a stack variable or (2) is something we cannot determine leads to -/// the address of a stack variable based on such local checking. +/// encounter a subexpression that (1) clearly does not lead to one of the +/// above problematic expressions (2) is something we cannot determine leads to +/// a problematic expression based on such local checking. +/// +/// Both EvalAddr and EvalVal follow through reference variables to evaluate +/// the expression that they point to. Such variables are added to the +/// 'refVars' vector so that we know what the reference variable "trail" was. /// /// EvalAddr processes expressions that are pointers that are used as /// references (and not L-values). EvalVal handles all other values. -/// At the base case of the recursion is a check for a DeclRefExpr* in -/// the refers to a stack variable. +/// At the base case of the recursion is a check for the above problematic +/// expressions. /// /// This implementation handles: /// @@ -1851,7 +1858,10 @@ Sema::CheckReturnStackAddr(Expr *RetValExp, QualType lhsType, /// * arbitrary interplay between "&" and "*" operators /// * pointer arithmetic from an address of a stack variable /// * taking the address of an array element where the array is on the stack -static DeclRefExpr* EvalAddr(Expr *E) { +static Expr *EvalAddr(Expr *E, llvm::SmallVectorImpl<DeclRefExpr *> &refVars) { + if (E->isTypeDependent()) + return NULL; + // We should only be called for evaluating pointer expressions. assert((E->getType()->isAnyPointerType() || E->getType()->isBlockPointerType() || @@ -1864,7 +1874,23 @@ static DeclRefExpr* EvalAddr(Expr *E) { switch (E->getStmtClass()) { case Stmt::ParenExprClass: // Ignore parentheses. - return EvalAddr(cast<ParenExpr>(E)->getSubExpr()); + return EvalAddr(cast<ParenExpr>(E)->getSubExpr(), refVars); + + case Stmt::DeclRefExprClass: { + DeclRefExpr *DR = cast<DeclRefExpr>(E); + + if (VarDecl *V = dyn_cast<VarDecl>(DR->getDecl())) + // If this is a reference variable, follow through to the expression that + // it points to. + if (V->hasLocalStorage() && + V->getType()->isReferenceType() && V->hasInit()) { + // Add the reference variable to the "trail". + refVars.push_back(DR); + return EvalAddr(V->getInit(), refVars); + } + + return NULL; + } case Stmt::UnaryOperatorClass: { // The only unary operator that make sense to handle here @@ -1872,7 +1898,7 @@ static DeclRefExpr* EvalAddr(Expr *E) { UnaryOperator *U = cast<UnaryOperator>(E); if (U->getOpcode() == UO_AddrOf) - return EvalVal(U->getSubExpr()); + return EvalVal(U->getSubExpr(), refVars); else return NULL; } @@ -1893,7 +1919,7 @@ static DeclRefExpr* EvalAddr(Expr *E) { if (!Base->getType()->isPointerType()) Base = B->getRHS(); assert (Base->getType()->isPointerType()); - return EvalAddr(Base); + return EvalAddr(Base, refVars); } // For conditional operators we need to see if either the LHS or RHS are @@ -1902,12 +1928,27 @@ static DeclRefExpr* EvalAddr(Expr *E) { ConditionalOperator *C = cast<ConditionalOperator>(E); // Handle the GNU extension for missing LHS. - if (Expr *lhsExpr = C->getLHS()) - if (DeclRefExpr* LHS = EvalAddr(lhsExpr)) - return LHS; + if (Expr *lhsExpr = C->getLHS()) { + // In C++, we can have a throw-expression, which has 'void' type. + if (!lhsExpr->getType()->isVoidType()) + if (Expr* LHS = EvalAddr(lhsExpr, refVars)) + return LHS; + } - return EvalAddr(C->getRHS()); + // In C++, we can have a throw-expression, which has 'void' type. + if (C->getRHS()->getType()->isVoidType()) + return NULL; + + return EvalAddr(C->getRHS(), refVars); } + + case Stmt::BlockExprClass: + if (cast<BlockExpr>(E)->getBlockDecl()->hasCaptures()) + return E; // local block. + return NULL; + + case Stmt::AddrLabelExprClass: + return E; // address of label. // For casts, we need to handle conversions from arrays to // pointer values, and pointer-to-pointer conversions. @@ -1920,9 +1961,9 @@ static DeclRefExpr* EvalAddr(Expr *E) { if (SubExpr->getType()->isPointerType() || SubExpr->getType()->isBlockPointerType() || SubExpr->getType()->isObjCQualifiedIdType()) - return EvalAddr(SubExpr); + return EvalAddr(SubExpr, refVars); else if (T->isArrayType()) - return EvalVal(SubExpr); + return EvalVal(SubExpr, refVars); else return 0; } @@ -1941,7 +1982,7 @@ static DeclRefExpr* EvalAddr(Expr *E) { case Stmt::CXXReinterpretCastExprClass: { Expr *S = cast<CXXNamedCastExpr>(E)->getSubExpr(); if (S->getType()->isPointerType() || S->getType()->isBlockPointerType()) - return EvalAddr(S); + return EvalAddr(S, refVars); else return NULL; } @@ -1955,7 +1996,7 @@ static DeclRefExpr* EvalAddr(Expr *E) { /// EvalVal - This function is complements EvalAddr in the mutual recursion. /// See the comments for EvalAddr for more details. -static DeclRefExpr* EvalVal(Expr *E) { +static Expr *EvalVal(Expr *E, llvm::SmallVectorImpl<DeclRefExpr *> &refVars) { do { // We should only be called for evaluating non-pointer expressions, or // expressions with a pointer type that are not used as references but instead @@ -1975,13 +2016,24 @@ do { } case Stmt::DeclRefExprClass: { - // DeclRefExpr: the base case. When we hit a DeclRefExpr we are looking - // at code that refers to a variable's name. We check if it has local - // storage within the function, and if so, return the expression. + // When we hit a DeclRefExpr we are looking at code that refers to a + // variable's name. If it's not a reference variable we check if it has + // local storage within the function, and if so, return the expression. DeclRefExpr *DR = cast<DeclRefExpr>(E); if (VarDecl *V = dyn_cast<VarDecl>(DR->getDecl())) - if (V->hasLocalStorage() && !V->getType()->isReferenceType()) return DR; + if (V->hasLocalStorage()) { + if (!V->getType()->isReferenceType()) + return DR; + + // Reference variable, follow through to the expression that + // it points to. + if (V->hasInit()) { + // Add the reference variable to the "trail". + refVars.push_back(DR); + return EvalVal(V->getInit(), refVars); + } + } return NULL; } @@ -1999,7 +2051,7 @@ do { UnaryOperator *U = cast<UnaryOperator>(E); if (U->getOpcode() == UO_Deref) - return EvalAddr(U->getSubExpr()); + return EvalAddr(U->getSubExpr(), refVars); return NULL; } @@ -2008,20 +2060,20 @@ do { // Array subscripts are potential references to data on the stack. We // retrieve the DeclRefExpr* for the array variable if it indeed // has local storage. - return EvalAddr(cast<ArraySubscriptExpr>(E)->getBase()); + return EvalAddr(cast<ArraySubscriptExpr>(E)->getBase(), refVars); } case Stmt::ConditionalOperatorClass: { // For conditional operators we need to see if either the LHS or RHS are - // non-NULL DeclRefExpr's. If one is non-NULL, we return it. + // non-NULL Expr's. If one is non-NULL, we return it. ConditionalOperator *C = cast<ConditionalOperator>(E); // Handle the GNU extension for missing LHS. if (Expr *lhsExpr = C->getLHS()) - if (DeclRefExpr *LHS = EvalVal(lhsExpr)) + if (Expr *LHS = EvalVal(lhsExpr, refVars)) return LHS; - return EvalVal(C->getRHS()); + return EvalVal(C->getRHS(), refVars); } // Accesses to members are potential references to data on the stack. @@ -2037,11 +2089,16 @@ do { if (M->getMemberDecl()->getType()->isReferenceType()) return NULL; - return EvalVal(M->getBase()); + return EvalVal(M->getBase(), refVars); } - // Everything else: we simply don't reason about them. default: + // Check that we don't return or take the address of a reference to a + // temporary. This is only useful in C++. + if (!E->isTypeDependent() && E->isRValue()) + return E; + + // Everything else: we simply don't reason about them. return NULL; } } while (true); @@ -2055,8 +2112,8 @@ do { void Sema::CheckFloatComparison(SourceLocation loc, Expr* lex, Expr *rex) { bool EmitWarning = true; - Expr* LeftExprSansParen = lex->IgnoreParens(); - Expr* RightExprSansParen = rex->IgnoreParens(); + Expr* LeftExprSansParen = lex->IgnoreParenImpCasts(); + Expr* RightExprSansParen = rex->IgnoreParenImpCasts(); // Special case: check for x == x (which is OK). // Do not emit warnings for such cases. @@ -2117,19 +2174,19 @@ struct IntRange { : Width(Width), NonNegative(NonNegative) {} - // Returns the range of the bool type. + /// Returns the range of the bool type. static IntRange forBoolType() { return IntRange(1, true); } - // Returns the range of an integral type. - static IntRange forType(ASTContext &C, QualType T) { - return forCanonicalType(C, T->getCanonicalTypeInternal().getTypePtr()); + /// Returns the range of an opaque value of the given integral type. + static IntRange forValueOfType(ASTContext &C, QualType T) { + return forValueOfCanonicalType(C, + T->getCanonicalTypeInternal().getTypePtr()); } - // Returns the range of an integeral type based on its canonical - // representation. - static IntRange forCanonicalType(ASTContext &C, const Type *T) { + /// Returns the range of an opaque value of a canonical integral type. + static IntRange forValueOfCanonicalType(ASTContext &C, const Type *T) { assert(T->isCanonicalUnqualified()); if (const VectorType *VT = dyn_cast<VectorType>(T)) @@ -2137,8 +2194,12 @@ struct IntRange { if (const ComplexType *CT = dyn_cast<ComplexType>(T)) T = CT->getElementType().getTypePtr(); + // For enum types, use the known bit width of the enumerators. if (const EnumType *ET = dyn_cast<EnumType>(T)) { EnumDecl *Enum = ET->getDecl(); + if (!Enum->isDefinition()) + return IntRange(C.getIntWidth(QualType(T, 0)), false); + unsigned NumPositive = Enum->getNumPositiveBits(); unsigned NumNegative = Enum->getNumNegativeBits(); @@ -2151,13 +2212,34 @@ struct IntRange { return IntRange(C.getIntWidth(QualType(T, 0)), BT->isUnsignedInteger()); } - // Returns the supremum of two ranges: i.e. their conservative merge. + /// Returns the "target" range of a canonical integral type, i.e. + /// the range of values expressible in the type. + /// + /// This matches forValueOfCanonicalType except that enums have the + /// full range of their type, not the range of their enumerators. + static IntRange forTargetOfCanonicalType(ASTContext &C, const Type *T) { + assert(T->isCanonicalUnqualified()); + + if (const VectorType *VT = dyn_cast<VectorType>(T)) + T = VT->getElementType().getTypePtr(); + if (const ComplexType *CT = dyn_cast<ComplexType>(T)) + T = CT->getElementType().getTypePtr(); + if (const EnumType *ET = dyn_cast<EnumType>(T)) + T = ET->getDecl()->getIntegerType().getTypePtr(); + + const BuiltinType *BT = cast<BuiltinType>(T); + assert(BT->isInteger()); + + return IntRange(C.getIntWidth(QualType(T, 0)), BT->isUnsignedInteger()); + } + + /// Returns the supremum of two ranges: i.e. their conservative merge. static IntRange join(IntRange L, IntRange R) { return IntRange(std::max(L.Width, R.Width), L.NonNegative && R.NonNegative); } - // Returns the infinum of two ranges: i.e. their aggressive merge. + /// Returns the infinum of two ranges: i.e. their aggressive merge. static IntRange meet(IntRange L, IntRange R) { return IntRange(std::min(L.Width, R.Width), L.NonNegative || R.NonNegative); @@ -2169,7 +2251,7 @@ IntRange GetValueRange(ASTContext &C, llvm::APSInt &value, unsigned MaxWidth) { return IntRange(value.getMinSignedBits(), false); if (value.getBitWidth() > MaxWidth) - value.trunc(MaxWidth); + value = value.trunc(MaxWidth); // isNonNegative() just checks the sign bit without considering // signedness. @@ -2224,11 +2306,9 @@ IntRange GetExprRange(ASTContext &C, Expr *E, unsigned MaxWidth) { if (CE->getCastKind() == CK_NoOp) return GetExprRange(C, CE->getSubExpr(), MaxWidth); - IntRange OutputTypeRange = IntRange::forType(C, CE->getType()); + IntRange OutputTypeRange = IntRange::forValueOfType(C, CE->getType()); bool isIntegerCast = (CE->getCastKind() == CK_IntegralCast); - if (!isIntegerCast && CE->getCastKind() == CK_Unknown) - isIntegerCast = CE->getSubExpr()->getType()->isIntegerType(); // Assume that non-integer casts can span the full range of the type. if (!isIntegerCast) @@ -2283,12 +2363,12 @@ IntRange GetExprRange(ASTContext &C, Expr *E, unsigned MaxWidth) { case BO_RemAssign: case BO_AddAssign: case BO_SubAssign: - return IntRange::forType(C, E->getType()); + return IntRange::forValueOfType(C, E->getType()); // Operations with opaque sources are black-listed. case BO_PtrMemD: case BO_PtrMemI: - return IntRange::forType(C, E->getType()); + return IntRange::forValueOfType(C, E->getType()); // Bitwise-and uses the *infinum* of the two source ranges. case BO_And: @@ -2303,14 +2383,14 @@ IntRange GetExprRange(ASTContext &C, Expr *E, unsigned MaxWidth) { if (IntegerLiteral *I = dyn_cast<IntegerLiteral>(BO->getLHS()->IgnoreParenCasts())) { if (I->getValue() == 1) { - IntRange R = IntRange::forType(C, E->getType()); + IntRange R = IntRange::forValueOfType(C, E->getType()); return IntRange(R.Width, /*NonNegative*/ true); } } // fallthrough case BO_ShlAssign: - return IntRange::forType(C, E->getType()); + return IntRange::forValueOfType(C, E->getType()); // Right shift by a constant can narrow its left argument. case BO_Shr: @@ -2339,7 +2419,7 @@ IntRange GetExprRange(ASTContext &C, Expr *E, unsigned MaxWidth) { // Black-list pointer subtractions. case BO_Sub: if (BO->getLHS()->getType()->isPointerType()) - return IntRange::forType(C, E->getType()); + return IntRange::forValueOfType(C, E->getType()); // fallthrough default: @@ -2362,7 +2442,7 @@ IntRange GetExprRange(ASTContext &C, Expr *E, unsigned MaxWidth) { // Operations with opaque sources are black-listed. case UO_Deref: case UO_AddrOf: // should be impossible - return IntRange::forType(C, E->getType()); + return IntRange::forValueOfType(C, E->getType()); default: return GetExprRange(C, UO->getSubExpr(), MaxWidth); @@ -2370,7 +2450,7 @@ IntRange GetExprRange(ASTContext &C, Expr *E, unsigned MaxWidth) { } if (dyn_cast<OffsetOfExpr>(E)) { - IntRange::forType(C, E->getType()); + IntRange::forValueOfType(C, E->getType()); } FieldDecl *BitField = E->getBitField(); @@ -2381,7 +2461,7 @@ IntRange GetExprRange(ASTContext &C, Expr *E, unsigned MaxWidth) { return IntRange(BitWidth, BitField->getType()->isUnsignedIntegerType()); } - return IntRange::forType(C, E->getType()); + return IntRange::forValueOfType(C, E->getType()); } IntRange GetExprRange(ASTContext &C, Expr *E) { @@ -2426,30 +2506,55 @@ bool IsSameFloatAfterCast(const APValue &value, IsSameFloatAfterCast(value.getComplexFloatImag(), Src, Tgt)); } -void AnalyzeImplicitConversions(Sema &S, Expr *E); +void AnalyzeImplicitConversions(Sema &S, Expr *E, SourceLocation CC); + +static bool IsZero(Sema &S, Expr *E) { + // Suppress cases where we are comparing against an enum constant. + if (const DeclRefExpr *DR = + dyn_cast<DeclRefExpr>(E->IgnoreParenImpCasts())) + if (isa<EnumConstantDecl>(DR->getDecl())) + return false; + + // Suppress cases where the '0' value is expanded from a macro. + if (E->getLocStart().isMacroID()) + return false; -bool IsZero(Sema &S, Expr *E) { llvm::APSInt Value; return E->isIntegerConstantExpr(Value, S.Context) && Value == 0; } +static bool HasEnumType(Expr *E) { + // Strip off implicit integral promotions. + while (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) { + if (ICE->getCastKind() != CK_IntegralCast && + ICE->getCastKind() != CK_NoOp) + break; + E = ICE->getSubExpr(); + } + + return E->getType()->isEnumeralType(); +} + void CheckTrivialUnsignedComparison(Sema &S, BinaryOperator *E) { BinaryOperatorKind op = E->getOpcode(); + if (E->isValueDependent()) + return; + if (op == BO_LT && IsZero(S, E->getRHS())) { S.Diag(E->getOperatorLoc(), diag::warn_lunsigned_always_true_comparison) - << "< 0" << "false" + << "< 0" << "false" << HasEnumType(E->getLHS()) << E->getLHS()->getSourceRange() << E->getRHS()->getSourceRange(); } else if (op == BO_GE && IsZero(S, E->getRHS())) { S.Diag(E->getOperatorLoc(), diag::warn_lunsigned_always_true_comparison) - << ">= 0" << "true" + << ">= 0" << "true" << HasEnumType(E->getLHS()) << E->getLHS()->getSourceRange() << E->getRHS()->getSourceRange(); } else if (op == BO_GT && IsZero(S, E->getLHS())) { S.Diag(E->getOperatorLoc(), diag::warn_runsigned_always_true_comparison) - << "0 >" << "false" + << "0 >" << "false" << HasEnumType(E->getRHS()) << E->getLHS()->getSourceRange() << E->getRHS()->getSourceRange(); } else if (op == BO_LE && IsZero(S, E->getLHS())) { S.Diag(E->getOperatorLoc(), diag::warn_runsigned_always_true_comparison) - << "0 <=" << "true" + << "0 <=" << "true" << HasEnumType(E->getRHS()) << E->getLHS()->getSourceRange() << E->getRHS()->getSourceRange(); } } @@ -2457,8 +2562,8 @@ void CheckTrivialUnsignedComparison(Sema &S, BinaryOperator *E) { /// Analyze the operands of the given comparison. Implements the /// fallback case from AnalyzeComparison. void AnalyzeImpConvsInComparison(Sema &S, BinaryOperator *E) { - AnalyzeImplicitConversions(S, E->getLHS()); - AnalyzeImplicitConversions(S, E->getRHS()); + AnalyzeImplicitConversions(S, E->getLHS(), E->getOperatorLoc()); + AnalyzeImplicitConversions(S, E->getRHS(), E->getOperatorLoc()); } /// \brief Implements -Wsign-compare. @@ -2476,7 +2581,11 @@ void AnalyzeComparison(Sema &S, BinaryOperator *E) { // We don't do anything special if this isn't an unsigned integral // comparison: we're only interested in integral comparisons, and // signed comparisons only happen in cases we don't care to warn about. - if (!T->hasUnsignedIntegerRepresentation()) + // + // We also don't care about value-dependent expressions or expressions + // whose result is a constant. + if (!T->hasUnsignedIntegerRepresentation() + || E->isValueDependent() || E->isIntegerConstantExpr(S.Context)) return AnalyzeImpConvsInComparison(S, E); Expr *lex = E->getLHS()->IgnoreParenImpCasts(); @@ -2503,8 +2612,8 @@ void AnalyzeComparison(Sema &S, BinaryOperator *E) { // Go ahead and analyze implicit conversions in the operands. Note // that we skip the implicit conversions on both sides. - AnalyzeImplicitConversions(S, lex); - AnalyzeImplicitConversions(S, rex); + AnalyzeImplicitConversions(S, lex, E->getOperatorLoc()); + AnalyzeImplicitConversions(S, rex, E->getOperatorLoc()); // If the signed range is non-negative, -Wsign-compare won't fire, // but we should still check for comparisons which are always true @@ -2533,13 +2642,103 @@ void AnalyzeComparison(Sema &S, BinaryOperator *E) { << lex->getSourceRange() << rex->getSourceRange(); } +/// Analyzes an attempt to assign the given value to a bitfield. +/// +/// Returns true if there was something fishy about the attempt. +bool AnalyzeBitFieldAssignment(Sema &S, FieldDecl *Bitfield, Expr *Init, + SourceLocation InitLoc) { + assert(Bitfield->isBitField()); + if (Bitfield->isInvalidDecl()) + return false; + + // White-list bool bitfields. + if (Bitfield->getType()->isBooleanType()) + return false; + + // Ignore value- or type-dependent expressions. + if (Bitfield->getBitWidth()->isValueDependent() || + Bitfield->getBitWidth()->isTypeDependent() || + Init->isValueDependent() || + Init->isTypeDependent()) + return false; + + Expr *OriginalInit = Init->IgnoreParenImpCasts(); + + llvm::APSInt Width(32); + Expr::EvalResult InitValue; + if (!Bitfield->getBitWidth()->isIntegerConstantExpr(Width, S.Context) || + !OriginalInit->Evaluate(InitValue, S.Context) || + !InitValue.Val.isInt()) + return false; + + const llvm::APSInt &Value = InitValue.Val.getInt(); + unsigned OriginalWidth = Value.getBitWidth(); + unsigned FieldWidth = Width.getZExtValue(); + + if (OriginalWidth <= FieldWidth) + return false; + + llvm::APSInt TruncatedValue = Value.trunc(FieldWidth); + + // It's fairly common to write values into signed bitfields + // that, if sign-extended, would end up becoming a different + // value. We don't want to warn about that. + if (Value.isSigned() && Value.isNegative()) + TruncatedValue = TruncatedValue.sext(OriginalWidth); + else + TruncatedValue = TruncatedValue.zext(OriginalWidth); + + if (Value == TruncatedValue) + return false; + + std::string PrettyValue = Value.toString(10); + std::string PrettyTrunc = TruncatedValue.toString(10); + + S.Diag(InitLoc, diag::warn_impcast_bitfield_precision_constant) + << PrettyValue << PrettyTrunc << OriginalInit->getType() + << Init->getSourceRange(); + + return true; +} + +/// Analyze the given simple or compound assignment for warning-worthy +/// operations. +void AnalyzeAssignment(Sema &S, BinaryOperator *E) { + // Just recurse on the LHS. + AnalyzeImplicitConversions(S, E->getLHS(), E->getOperatorLoc()); + + // We want to recurse on the RHS as normal unless we're assigning to + // a bitfield. + if (FieldDecl *Bitfield = E->getLHS()->getBitField()) { + if (AnalyzeBitFieldAssignment(S, Bitfield, E->getRHS(), + E->getOperatorLoc())) { + // Recurse, ignoring any implicit conversions on the RHS. + return AnalyzeImplicitConversions(S, E->getRHS()->IgnoreParenImpCasts(), + E->getOperatorLoc()); + } + } + + AnalyzeImplicitConversions(S, E->getRHS(), E->getOperatorLoc()); +} + /// Diagnose an implicit cast; purely a helper for CheckImplicitConversion. -void DiagnoseImpCast(Sema &S, Expr *E, QualType T, unsigned diag) { - S.Diag(E->getExprLoc(), diag) << E->getType() << T << E->getSourceRange(); +void DiagnoseImpCast(Sema &S, Expr *E, QualType T, SourceLocation CContext, + unsigned diag) { + S.Diag(E->getExprLoc(), diag) + << E->getType() << T << E->getSourceRange() << SourceRange(CContext); +} + +std::string PrettyPrintInRange(const llvm::APSInt &Value, IntRange Range) { + if (!Range.Width) return "0"; + + llvm::APSInt ValueInRange = Value; + ValueInRange.setIsSigned(!Range.NonNegative); + ValueInRange = ValueInRange.trunc(Range.Width); + return ValueInRange.toString(10); } void CheckImplicitConversion(Sema &S, Expr *E, QualType T, - bool *ICContext = 0) { + SourceLocation CC, bool *ICContext = 0) { if (E->isTypeDependent() || E->isValueDependent()) return; const Type *Source = S.Context.getCanonicalType(E->getType()).getTypePtr(); @@ -2547,6 +2746,13 @@ void CheckImplicitConversion(Sema &S, Expr *E, QualType T, if (Source == Target) return; if (Target->isDependentType()) return; + // If the conversion context location is invalid or instantiated + // from a system macro, don't complain. + if (CC.isInvalid() || + (CC.isMacroID() && S.Context.getSourceManager().isInSystemHeader( + S.Context.getSourceManager().getSpellingLoc(CC)))) + return; + // Never diagnose implicit casts to bool. if (Target->isSpecificBuiltinType(BuiltinType::Bool)) return; @@ -2554,7 +2760,7 @@ void CheckImplicitConversion(Sema &S, Expr *E, QualType T, // Strip vector types. if (isa<VectorType>(Source)) { if (!isa<VectorType>(Target)) - return DiagnoseImpCast(S, E, T, diag::warn_impcast_vector_scalar); + return DiagnoseImpCast(S, E, T, CC, diag::warn_impcast_vector_scalar); Source = cast<VectorType>(Source)->getElementType().getTypePtr(); Target = cast<VectorType>(Target)->getElementType().getTypePtr(); @@ -2563,7 +2769,7 @@ void CheckImplicitConversion(Sema &S, Expr *E, QualType T, // Strip complex types. if (isa<ComplexType>(Source)) { if (!isa<ComplexType>(Target)) - return DiagnoseImpCast(S, E, T, diag::warn_impcast_complex_scalar); + return DiagnoseImpCast(S, E, T, CC, diag::warn_impcast_complex_scalar); Source = cast<ComplexType>(Source)->getElementType().getTypePtr(); Target = cast<ComplexType>(Target)->getElementType().getTypePtr(); @@ -2591,15 +2797,21 @@ void CheckImplicitConversion(Sema &S, Expr *E, QualType T, return; } - DiagnoseImpCast(S, E, T, diag::warn_impcast_float_precision); + DiagnoseImpCast(S, E, T, CC, diag::warn_impcast_float_precision); } return; } // If the target is integral, always warn. - if ((TargetBT && TargetBT->isInteger())) - // TODO: don't warn for integer values? - DiagnoseImpCast(S, E, T, diag::warn_impcast_float_integer); + if ((TargetBT && TargetBT->isInteger())) { + Expr *InnerE = E->IgnoreParenImpCasts(); + if (FloatingLiteral *LiteralExpr = dyn_cast<FloatingLiteral>(InnerE)) { + DiagnoseImpCast(S, LiteralExpr, T, CC, + diag::warn_impcast_literal_float_to_integer); + } else { + DiagnoseImpCast(S, E, T, CC, diag::warn_impcast_float_integer); + } + } return; } @@ -2608,14 +2820,27 @@ void CheckImplicitConversion(Sema &S, Expr *E, QualType T, return; IntRange SourceRange = GetExprRange(S.Context, E); - IntRange TargetRange = IntRange::forCanonicalType(S.Context, Target); + IntRange TargetRange = IntRange::forTargetOfCanonicalType(S.Context, Target); if (SourceRange.Width > TargetRange.Width) { + // If the source is a constant, use a default-on diagnostic. + // TODO: this should happen for bitfield stores, too. + llvm::APSInt Value(32); + if (E->isIntegerConstantExpr(Value, S.Context)) { + std::string PrettySourceValue = Value.toString(10); + std::string PrettyTargetValue = PrettyPrintInRange(Value, TargetRange); + + S.Diag(E->getExprLoc(), diag::warn_impcast_integer_precision_constant) + << PrettySourceValue << PrettyTargetValue + << E->getType() << T << E->getSourceRange() << clang::SourceRange(CC); + return; + } + // People want to build with -Wshorten-64-to-32 and not -Wconversion // and by god we'll let them. if (SourceRange.Width == 64 && TargetRange.Width == 32) - return DiagnoseImpCast(S, E, T, diag::warn_impcast_integer_64_32); - return DiagnoseImpCast(S, E, T, diag::warn_impcast_integer_precision); + return DiagnoseImpCast(S, E, T, CC, diag::warn_impcast_integer_64_32); + return DiagnoseImpCast(S, E, T, CC, diag::warn_impcast_integer_precision); } if ((TargetRange.NonNegative && !SourceRange.NonNegative) || @@ -2633,7 +2858,7 @@ void CheckImplicitConversion(Sema &S, Expr *E, QualType T, *ICContext = true; } - return DiagnoseImpCast(S, E, T, DiagID); + return DiagnoseImpCast(S, E, T, CC, DiagID); } return; @@ -2642,35 +2867,38 @@ void CheckImplicitConversion(Sema &S, Expr *E, QualType T, void CheckConditionalOperator(Sema &S, ConditionalOperator *E, QualType T); void CheckConditionalOperand(Sema &S, Expr *E, QualType T, - bool &ICContext) { + SourceLocation CC, bool &ICContext) { E = E->IgnoreParenImpCasts(); if (isa<ConditionalOperator>(E)) return CheckConditionalOperator(S, cast<ConditionalOperator>(E), T); - AnalyzeImplicitConversions(S, E); + AnalyzeImplicitConversions(S, E, CC); if (E->getType() != T) - return CheckImplicitConversion(S, E, T, &ICContext); + return CheckImplicitConversion(S, E, T, CC, &ICContext); return; } void CheckConditionalOperator(Sema &S, ConditionalOperator *E, QualType T) { - AnalyzeImplicitConversions(S, E->getCond()); + SourceLocation CC = E->getQuestionLoc(); + + AnalyzeImplicitConversions(S, E->getCond(), CC); bool Suspicious = false; - CheckConditionalOperand(S, E->getTrueExpr(), T, Suspicious); - CheckConditionalOperand(S, E->getFalseExpr(), T, Suspicious); + CheckConditionalOperand(S, E->getTrueExpr(), T, CC, Suspicious); + CheckConditionalOperand(S, E->getFalseExpr(), T, CC, Suspicious); // If -Wconversion would have warned about either of the candidates // for a signedness conversion to the context type... if (!Suspicious) return; // ...but it's currently ignored... - if (S.Diags.getDiagnosticLevel(diag::warn_impcast_integer_sign_conditional)) + if (S.Diags.getDiagnosticLevel(diag::warn_impcast_integer_sign_conditional, + CC)) return; // ...and -Wsign-compare isn't... - if (!S.Diags.getDiagnosticLevel(diag::warn_mixed_sign_conditional)) + if (!S.Diags.getDiagnosticLevel(diag::warn_mixed_sign_conditional, CC)) return; // ...then check whether it would have warned about either of the @@ -2678,10 +2906,10 @@ void CheckConditionalOperator(Sema &S, ConditionalOperator *E, QualType T) { if (E->getType() != T) { Suspicious = false; CheckImplicitConversion(S, E->getTrueExpr()->IgnoreParenImpCasts(), - E->getType(), &Suspicious); + E->getType(), CC, &Suspicious); if (!Suspicious) CheckImplicitConversion(S, E->getFalseExpr()->IgnoreParenImpCasts(), - E->getType(), &Suspicious); + E->getType(), CC, &Suspicious); if (!Suspicious) return; } @@ -2697,7 +2925,7 @@ void CheckConditionalOperator(Sema &S, ConditionalOperator *E, QualType T) { /// AnalyzeImplicitConversions - Find and report any interesting /// implicit conversions in the given expression. There are a couple /// of competing diagnostics here, -Wconversion and -Wsign-compare. -void AnalyzeImplicitConversions(Sema &S, Expr *OrigE) { +void AnalyzeImplicitConversions(Sema &S, Expr *OrigE, SourceLocation CC) { QualType T = OrigE->getType(); Expr *E = OrigE->IgnoreParenImpCasts(); @@ -2713,19 +2941,25 @@ void AnalyzeImplicitConversions(Sema &S, Expr *OrigE) { // The non-canonical typecheck is just an optimization; // CheckImplicitConversion will filter out dead implicit conversions. if (E->getType() != T) - CheckImplicitConversion(S, E, T); + CheckImplicitConversion(S, E, T, CC); // Now continue drilling into this expression. // Skip past explicit casts. if (isa<ExplicitCastExpr>(E)) { E = cast<ExplicitCastExpr>(E)->getSubExpr()->IgnoreParenImpCasts(); - return AnalyzeImplicitConversions(S, E); + return AnalyzeImplicitConversions(S, E, CC); } - // Do a somewhat different check with comparison operators. - if (isa<BinaryOperator>(E) && cast<BinaryOperator>(E)->isComparisonOp()) - return AnalyzeComparison(S, cast<BinaryOperator>(E)); + if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) { + // Do a somewhat different check with comparison operators. + if (BO->isComparisonOp()) + return AnalyzeComparison(S, BO); + + // And with assignments and compound assignments. + if (BO->isAssignmentOp()) + return AnalyzeAssignment(S, BO); + } // These break the otherwise-useful invariant below. Fortunately, // we don't really need to recurse into them, because any internal @@ -2737,9 +2971,9 @@ void AnalyzeImplicitConversions(Sema &S, Expr *OrigE) { if (isa<SizeOfAlignOfExpr>(E)) return; // Now just recurse over the expression's children. - for (Stmt::child_iterator I = E->child_begin(), IE = E->child_end(); - I != IE; ++I) - AnalyzeImplicitConversions(S, cast<Expr>(*I)); + CC = E->getExprLoc(); + for (Stmt::child_range I = E->children(); I; ++I) + AnalyzeImplicitConversions(S, cast<Expr>(*I), CC); } } // end anonymous namespace @@ -2747,7 +2981,11 @@ void AnalyzeImplicitConversions(Sema &S, Expr *OrigE) { /// Diagnoses "dangerous" implicit conversions within the given /// expression (which is a full expression). Implements -Wconversion /// and -Wsign-compare. -void Sema::CheckImplicitConversions(Expr *E) { +/// +/// \param CC the "context" location of the implicit conversion, i.e. +/// the most location of the syntactic entity requiring the implicit +/// conversion +void Sema::CheckImplicitConversions(Expr *E, SourceLocation CC) { // Don't diagnose in unevaluated contexts. if (ExprEvalContexts.back().Context == Sema::Unevaluated) return; @@ -2756,7 +2994,14 @@ void Sema::CheckImplicitConversions(Expr *E) { if (E->isTypeDependent() || E->isValueDependent()) return; - AnalyzeImplicitConversions(*this, E); + // This is not the right CC for (e.g.) a variable initialization. + AnalyzeImplicitConversions(*this, E, CC); +} + +void Sema::CheckBitFieldInitialization(SourceLocation InitLoc, + FieldDecl *BitField, + Expr *Init) { + (void) AnalyzeBitFieldAssignment(*this, BitField, Init, InitLoc); } /// CheckParmsForFunctionDef - Check that the parameters of the given @@ -2764,11 +3009,12 @@ void Sema::CheckImplicitConversions(Expr *E) { /// takes care of any checks that cannot be performed on the /// declaration itself, e.g., that the types of each of the function /// parameters are complete. -bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { +bool Sema::CheckParmsForFunctionDef(ParmVarDecl **P, ParmVarDecl **PEnd, + bool CheckParameterNames) { bool HasInvalidParm = false; - for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { - ParmVarDecl *Param = FD->getParamDecl(p); - + for (; P != PEnd; ++P) { + ParmVarDecl *Param = *P; + // C99 6.7.5.3p4: the parameters in a parameter type list in a // function declarator that is part of a function definition of // that function shall not have incomplete type. @@ -2783,7 +3029,8 @@ bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { // C99 6.9.1p5: If the declarator includes a parameter type list, the // declaration of each parameter shall include an identifier. - if (Param->getIdentifier() == 0 && + if (CheckParameterNames && + Param->getIdentifier() == 0 && !Param->isImplicit() && !getLangOptions().CPlusPlus) Diag(Param->getLocation(), diag::err_parameter_name_omitted); @@ -2811,7 +3058,8 @@ bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { void Sema::CheckCastAlign(Expr *Op, QualType T, SourceRange TRange) { // This is actually a lot of work to potentially be doing on every // cast; don't do it if we're ignoring -Wcast_align (as is the default). - if (getDiagnostics().getDiagnosticLevel(diag::warn_cast_align) + if (getDiagnostics().getDiagnosticLevel(diag::warn_cast_align, + TRange.getBegin()) == Diagnostic::Ignored) return; @@ -2850,3 +3098,47 @@ void Sema::CheckCastAlign(Expr *Op, QualType T, SourceRange TRange) { << TRange << Op->getSourceRange(); } +void Sema::CheckArrayAccess(const clang::ArraySubscriptExpr *E) { + const Expr *BaseExpr = E->getBase()->IgnoreParenImpCasts(); + const ConstantArrayType *ArrayTy = + Context.getAsConstantArrayType(BaseExpr->getType()); + if (!ArrayTy) + return; + + const Expr *IndexExpr = E->getIdx(); + if (IndexExpr->isValueDependent()) + return; + llvm::APSInt index; + if (!IndexExpr->isIntegerConstantExpr(index, Context)) + return; + + if (!index.isNegative()) { + llvm::APInt size = ArrayTy->getSize(); + if (!size.isStrictlyPositive()) + return; + if (size.getBitWidth() > index.getBitWidth()) + index = index.sext(size.getBitWidth()); + else if (size.getBitWidth() < index.getBitWidth()) + size = size.sext(index.getBitWidth()); + + if (index.slt(size)) + return; + + Diag(E->getBase()->getLocStart(), diag::warn_array_index_exceeds_bounds) + << index.toString(10, true) << size.toString(10, true) + << IndexExpr->getSourceRange(); + } else { + Diag(E->getBase()->getLocStart(), diag::warn_array_index_precedes_bounds) + << index.toString(10, true) << IndexExpr->getSourceRange(); + } + + const NamedDecl *ND = NULL; + if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(BaseExpr)) + ND = dyn_cast<NamedDecl>(DRE->getDecl()); + if (const MemberExpr *ME = dyn_cast<MemberExpr>(BaseExpr)) + ND = dyn_cast<NamedDecl>(ME->getMemberDecl()); + if (ND) + Diag(ND->getLocStart(), diag::note_array_index_out_of_bounds) + << ND->getDeclName(); +} + |
