Reapply [Sema] Add sizeof diagnostics for bzero
Reapply r277787. For memset (and others) we can get diagnostics like:
struct stat { int x; };
void foo(struct stat *stamps) {
bzero(stamps, sizeof(stamps));
memset(stamps, 0, sizeof(stamps));
}
t.c:7:28: warning: 'memset' call operates on objects of type 'struct stat' while the size is based on a different type 'struct stat *' [-Wsizeof-pointer-memaccess]
memset(stamps, 0, sizeof(stamps));
~~~~~~ ^~~~~~
t.c:7:28: note: did you mean to dereference the argument to 'sizeof' (and multiply it by the number of elements)?
memset(stamps, 0, sizeof(stamps));
^~~~~~
This patch implements the same class of warnings for bzero.
Differential Revision: https://reviews.llvm.org/D22525
rdar://problem/18963514
llvm-svn: 278264
diff --git a/clang/lib/Sema/SemaChecking.cpp b/clang/lib/Sema/SemaChecking.cpp
index fd90121..f76ab08 100644
--- a/clang/lib/Sema/SemaChecking.cpp
+++ b/clang/lib/Sema/SemaChecking.cpp
@@ -6179,13 +6179,15 @@
// It is possible to have a non-standard definition of memset. Validate
// we have enough arguments, and if not, abort further checking.
- unsigned ExpectedNumArgs = (BId == Builtin::BIstrndup ? 2 : 3);
+ unsigned ExpectedNumArgs =
+ (BId == Builtin::BIstrndup || BId == Builtin::BIbzero ? 2 : 3);
if (Call->getNumArgs() < ExpectedNumArgs)
return;
- unsigned LastArg = (BId == Builtin::BImemset ||
+ unsigned LastArg = (BId == Builtin::BImemset || BId == Builtin::BIbzero ||
BId == Builtin::BIstrndup ? 1 : 2);
- unsigned LenArg = (BId == Builtin::BIstrndup ? 1 : 2);
+ unsigned LenArg =
+ (BId == Builtin::BIbzero || BId == Builtin::BIstrndup ? 1 : 2);
const Expr *LenExpr = Call->getArg(LenArg)->IgnoreParenImpCasts();
if (CheckMemorySizeofForComparison(*this, LenExpr, FnName,