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| author | Erik Pilkington <erik.pilkington@gmail.com> | 2018-07-23 16:24:14 +0000 |
|---|---|---|
| committer | Erik Pilkington <erik.pilkington@gmail.com> | 2018-07-23 16:24:14 +0000 |
| commit | c79b881ccd63fdedf917b2e766f02860dc97d124 (patch) | |
| tree | f3702af83e40d220a218aa56d8394d5a08e534d7 | |
| parent | 307e5b31ce7149e04a0357a48f7d1904b4c00233 (diff) | |
| download | bcm5719-llvm-c79b881ccd63fdedf917b2e766f02860dc97d124.tar.gz bcm5719-llvm-c79b881ccd63fdedf917b2e766f02860dc97d124.zip | |
[Sema] Don't emit -Wmemset-transposed-args for memset(p,0,0)
Thanks to Arthur O'Dwyer for the suggestion!
llvm-svn: 337706
| -rw-r--r-- | clang/lib/Sema/SemaChecking.cpp | 9 | ||||
| -rw-r--r-- | clang/test/Sema/transpose-memset.c | 3 |
2 files changed, 8 insertions, 4 deletions
diff --git a/clang/lib/Sema/SemaChecking.cpp b/clang/lib/Sema/SemaChecking.cpp index 1e72083f3c7..6492346f6ac 100644 --- a/clang/lib/Sema/SemaChecking.cpp +++ b/clang/lib/Sema/SemaChecking.cpp @@ -8788,11 +8788,14 @@ static void CheckMemaccessSize(Sema &S, unsigned BId, const CallExpr *Call) { const Expr *SizeArg = Call->getArg(BId == Builtin::BImemset ? 2 : 1)->IgnoreImpCasts(); + auto isLiteralZero = [](const Expr *E) { + return isa<IntegerLiteral>(E) && cast<IntegerLiteral>(E)->getValue() == 0; + }; + // If we're memsetting or bzeroing 0 bytes, then this is likely an error. SourceLocation CallLoc = Call->getRParenLoc(); SourceManager &SM = S.getSourceManager(); - if (isa<IntegerLiteral>(SizeArg) && - cast<IntegerLiteral>(SizeArg)->getValue() == 0 && + if (isLiteralZero(SizeArg) && !isArgumentExpandedFromMacro(SM, CallLoc, SizeArg->getExprLoc())) { SourceLocation DiagLoc = SizeArg->getExprLoc(); @@ -8804,7 +8807,7 @@ static void CheckMemaccessSize(Sema &S, unsigned BId, const CallExpr *Call) { CallLoc, SM, S.getLangOpts()) == "bzero")) { S.Diag(DiagLoc, diag::warn_suspicious_bzero_size); S.Diag(DiagLoc, diag::note_suspicious_bzero_size_silence); - } else { + } else if (!isLiteralZero(Call->getArg(1)->IgnoreImpCasts())) { S.Diag(DiagLoc, diag::warn_suspicious_sizeof_memset) << 0; S.Diag(DiagLoc, diag::note_suspicious_sizeof_memset_silence) << 0; } diff --git a/clang/test/Sema/transpose-memset.c b/clang/test/Sema/transpose-memset.c index 0180d5051e5..6112fde3406 100644 --- a/clang/test/Sema/transpose-memset.c +++ b/clang/test/Sema/transpose-memset.c @@ -22,6 +22,7 @@ int main() { memset(array, (int)sizeof(array), (0)); // no warning memset(array, (int)sizeof(array), 32); // no warning memset(array, 32, (0)); // no warning + memset(array, 0, 0); // no warning bzero(ptr, 0); // expected-warning{{'size' argument to bzero is '0'}} expected-note{{parenthesize the second argument to silence}} real_bzero(ptr, 0); // expected-warning{{'size' argument to bzero is '0'}} expected-note{{parenthesize the second argument to silence}} @@ -55,6 +56,6 @@ void macros() { __builtin_memset(array, 0, ZERO); // no warning __builtin_bzero(array, ZERO); - __builtin_memset(array, 0, 0); // expected-warning{{'size' argument to memset}} // expected-note{{parenthesize}} + __builtin_memset(array, 1, 0); // expected-warning{{'size' argument to memset}} // expected-note{{parenthesize}} __builtin_bzero(array, 0); // expected-warning{{'size' argument to bzero}} // expected-note{{parenthesize}} } |
