1 files changed, 19 insertions, 14 deletions

diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index 90499d2749..073da57b36 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -10874,11 +10874,6 @@ Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
       while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC))
         SearchDC = SearchDC->getParent();
     }
-  } else if (S->isFunctionPrototypeScope()) {
-    // If this is an enum declaration in function prototype scope, set its
-    // initial context to the translation unit.
-    // FIXME: [citation needed]
-    SearchDC = Context.getTranslationUnitDecl();
   }
 
   if (Previous.isSingleResult() &&
@@ -11351,27 +11346,37 @@ CreateNewDecl:
     else if (!SearchDC->isFunctionOrMethod())
       New->setModulePrivate();
   }
-  
+
   // If this is a specialization of a member class (of a class template),
   // check the specialization.
   if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous))
     Invalid = true;
-           
-  if (Invalid)
-    New->setInvalidDecl();
-
-  if (Attr)
-    ProcessDeclAttributeList(S, New, Attr);
 
   // If we're declaring or defining a tag in function prototype scope in C,
   // note that this type can only be used within the function and add it to
   // the list of decls to inject into the function definition scope.
-  if (!getLangOpts().CPlusPlus && (Name || Kind == TTK_Enum) &&
+  if ((Name || Kind == TTK_Enum) &&
       getNonFieldDeclScope(S)->isFunctionPrototypeScope()) {
-    Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New);
+    if (getLangOpts().CPlusPlus) {
+      // C++ [dcl.fct]p6:
+      //   Types shall not be defined in return or parameter types.
+      if (TUK == TUK_Definition && !IsTypeSpecifier) {
+        Diag(Loc, diag::err_type_defined_in_param_type)
+            << Name;
+        Invalid = true;
+      }
+    } else {
+      Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New);
+    }
     DeclsInPrototypeScope.push_back(New);
   }
 
+  if (Invalid)
+    New->setInvalidDecl();
+
+  if (Attr)
+    ProcessDeclAttributeList(S, New, Attr);
+
   // Set the lexical context. If the tag has a C++ scope specifier, the
   // lexical context will be different from the semantic context.
   New->setLexicalDeclContext(CurContext);