Daniel convinced me that accepting "const va_list" arguments to va_arg is
a really really bad idea.  Now that we emit an error about the unpromoted
type, users should be able to understand what is going on.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@68447 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index e81fc49..1bdabad 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -1464,8 +1464,6 @@
   "'va_start' used in function with fixed args">;
 def warn_second_parameter_of_va_start_not_last_named_argument : Warning<
   "second parameter of 'va_start' not last named argument">;
-def warn_va_arg_with_qualified_va_list : Warning<
-  "va_arg applied to va_list type %0 with unexpected qualifiers">;
 def err_first_argument_to_va_arg_not_of_type_va_list : Error<
   "first argument to 'va_arg' is of type %0 and not 'va_list'">;
 
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index 99afd32..602f7fc 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -4725,16 +4725,7 @@
   // Make sure the input expression also decays appropriately.
   UsualUnaryConversions(E);
 
-  AssignConvertType ConvResult = 
-    CheckAssignmentConstraints(VaListType, E->getType());
-  switch (ConvResult) {
-  case Compatible: break;  // Everything good.
-  case CompatiblePointerDiscardsQualifiers:
-    Diag(E->getLocStart(), diag::warn_va_arg_with_qualified_va_list)
-      << OrigExpr->getType() << E->getSourceRange();
-    break;
-
-  default:
+  if (CheckAssignmentConstraints(VaListType, E->getType()) != Compatible) {
     return ExprError(Diag(E->getLocStart(),
                          diag::err_first_argument_to_va_arg_not_of_type_va_list)
       << OrigExpr->getType() << E->getSourceRange());
diff --git a/test/Sema/varargs-x86-64.c b/test/Sema/varargs-x86-64.c
index 5afcda2..7c71c96 100644
--- a/test/Sema/varargs-x86-64.c
+++ b/test/Sema/varargs-x86-64.c
@@ -3,6 +3,6 @@
 // rdar://6726818
 void f1() {
   const __builtin_va_list args2;
-  (void)__builtin_va_arg(args2, int); // expected-warning {{va_arg applied to va_list type '__builtin_va_list const' with unexpected qualifiers}}
+  (void)__builtin_va_arg(args2, int); // expected-error {{first argument to 'va_arg' is of type '__builtin_va_list const' and not 'va_list'}}
 }