-Wformat: better handling of qualifiers on pointer arguments
Warn about using pointers to const-qualified types as arguments to
scanf. Ignore the volatile qualifier when checking if types match.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@161052 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/ScanfFormatString.cpp b/lib/Analysis/ScanfFormatString.cpp
index 3c848f1..1bbd5f2 100644
--- a/lib/Analysis/ScanfFormatString.cpp
+++ b/lib/Analysis/ScanfFormatString.cpp
@@ -453,6 +453,15 @@
}
bool ScanfArgTypeResult::matchesType(ASTContext& C, QualType argTy) const {
+ // It has to be a pointer type.
+ const PointerType *PT = argTy->getAs<PointerType>();
+ if (!PT)
+ return false;
+
+ // We cannot write through a const qualified pointer.
+ if (PT->getPointeeType().isConstQualified())
+ return false;
+
switch (K) {
case InvalidTy:
llvm_unreachable("ArgTypeResult must be valid");
@@ -463,9 +472,6 @@
case WCStrTy:
return ArgTypeResult(ArgTypeResult::WCStrTy).matchesType(C, argTy);
case PtrToArgTypeResultTy: {
- const PointerType *PT = argTy->getAs<PointerType>();
- if (!PT)
- return false;
return A.matchesType(C, PT->getPointeeType());
}
}