Add stricter checking for va_arg.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@71942 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index ea0d22c..4145be6 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -5208,15 +5208,21 @@
// Get the va_list type
QualType VaListType = Context.getBuiltinVaListType();
- // Deal with implicit array decay; for example, on x86-64,
- // va_list is an array, but it's supposed to decay to
- // a pointer for va_arg.
- if (VaListType->isArrayType())
+ if (VaListType->isArrayType()) {
+ // Deal with implicit array decay; for example, on x86-64,
+ // va_list is an array, but it's supposed to decay to
+ // a pointer for va_arg.
VaListType = Context.getArrayDecayedType(VaListType);
- // Make sure the input expression also decays appropriately.
- UsualUnaryConversions(E);
+ // Make sure the input expression also decays appropriately.
+ UsualUnaryConversions(E);
+ } else {
+ // Otherwise, the va_list argument must be an l-value because
+ // it is modified by va_arg.
+ if (CheckForModifiableLvalue(E, BuiltinLoc, *this))
+ return ExprError();
+ }
- if (CheckAssignmentConstraints(VaListType, E->getType()) != Compatible) {
+ if (!Context.hasSameType(VaListType, E->getType())) {
return ExprError(Diag(E->getLocStart(),
diag::err_first_argument_to_va_arg_not_of_type_va_list)
<< OrigExpr->getType() << E->getSourceRange());