Author: danielmarjamaki Date: Fri Feb 12 01:51:10 2016 New Revision: 260665
URL: http://llvm.org/viewvc/llvm-project?rev=260665&view=rev Log: [clang-tidy] improve misc-misplaced-widening-cast so it also detects portability problems. Reviewers: alexfh Subscribers: cfe-commits Differential Revision: http://reviews.llvm.org/D17140 Modified: clang-tools-extra/trunk/clang-tidy/misc/MisplacedWideningCastCheck.cpp clang-tools-extra/trunk/test/clang-tidy/misc-misplaced-widening-cast.cpp Modified: clang-tools-extra/trunk/clang-tidy/misc/MisplacedWideningCastCheck.cpp URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clang-tidy/misc/MisplacedWideningCastCheck.cpp?rev=260665&r1=260664&r2=260665&view=diff ============================================================================== --- clang-tools-extra/trunk/clang-tidy/misc/MisplacedWideningCastCheck.cpp (original) +++ clang-tools-extra/trunk/clang-tidy/misc/MisplacedWideningCastCheck.cpp Fri Feb 12 01:51:10 2016 @@ -27,8 +27,7 @@ void MisplacedWideningCastCheck::registe auto Cast = explicitCastExpr(anyOf(cStyleCastExpr(), cxxStaticCastExpr(), cxxReinterpretCastExpr()), - hasDestinationType(isInteger()), - has(Calc)) + hasDestinationType(isInteger()), has(Calc)) .bind("Cast"); Finder->addMatcher(varDecl(has(Cast)), this); @@ -90,9 +89,29 @@ void MisplacedWideningCastCheck::check(c QualType CastType = Cast->getType(); QualType CalcType = Calc->getType(); - if (Context.getIntWidth(CastType) <= Context.getIntWidth(CalcType)) + // Explicit truncation using cast. + if (Context.getIntWidth(CastType) < Context.getIntWidth(CalcType)) return; + // If CalcType and CastType have same size then there is no real danger, but + // there can be a portability problem. + if (Context.getIntWidth(CastType) == Context.getIntWidth(CalcType)) { + if (CalcType->isSpecificBuiltinType(BuiltinType::Int)) { + // There should be a warning when casting from int to long or long long. + if (!CastType->isSpecificBuiltinType(BuiltinType::Long) && + !CastType->isSpecificBuiltinType(BuiltinType::LongLong)) + return; + } else if (CalcType->isSpecificBuiltinType(BuiltinType::Long)) { + // There should be a warning when casting from long to long long. + if (!CastType->isSpecificBuiltinType(BuiltinType::LongLong)) + return; + } else { + return; + } + } + + // Don't write a warning if we can easily see that the result is not + // truncated. if (Context.getIntWidth(CalcType) >= getMaxCalculationWidth(Context, Calc)) return; Modified: clang-tools-extra/trunk/test/clang-tidy/misc-misplaced-widening-cast.cpp URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/test/clang-tidy/misc-misplaced-widening-cast.cpp?rev=260665&r1=260664&r2=260665&view=diff ============================================================================== --- clang-tools-extra/trunk/test/clang-tidy/misc-misplaced-widening-cast.cpp (original) +++ clang-tools-extra/trunk/test/clang-tidy/misc-misplaced-widening-cast.cpp Fri Feb 12 01:51:10 2016 @@ -1,4 +1,4 @@ -// RUN: %check_clang_tidy %s misc-misplaced-widening-cast %t -- -- -target x86_64-unknown-unknown +// RUN: %check_clang_tidy %s misc-misplaced-widening-cast %t void assign(int a, int b) { long l; _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
