Tighten types a bit. No functionality change.

llvm-svn: 171902
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index 58ba3ee..5b610b9 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -1788,23 +1788,19 @@
   return false;
 }
 
-bool Sema::mergeDeclAttribute(Decl *D, InheritableAttr *Attr) {
+bool Sema::mergeDeclAttribute(NamedDecl *D, InheritableAttr *Attr) {
   InheritableAttr *NewAttr = NULL;
   if (AvailabilityAttr *AA = dyn_cast<AvailabilityAttr>(Attr)) {
     NewAttr = mergeAvailabilityAttr(D, AA->getRange(), AA->getPlatform(),
                                     AA->getIntroduced(), AA->getDeprecated(),
                                     AA->getObsoleted(), AA->getUnavailable(),
                                     AA->getMessage());
-    if (NewAttr) {
-      NamedDecl *ND = cast<NamedDecl>(D);
-      ND->ClearLVCache();
-    }
+    if (NewAttr)
+      D->ClearLVCache();
   } else if (VisibilityAttr *VA = dyn_cast<VisibilityAttr>(Attr)) {
     NewAttr = mergeVisibilityAttr(D, VA->getRange(), VA->getVisibility());
-    if (NewAttr) {
-      NamedDecl *ND = cast<NamedDecl>(D);
-      ND->ClearLVCache();
-    }
+    if (NewAttr)
+      D->ClearLVCache();
   } else if (DLLImportAttr *ImportA = dyn_cast<DLLImportAttr>(Attr))
     NewAttr = mergeDLLImportAttr(D, ImportA->getRange());
   else if (DLLExportAttr *ExportA = dyn_cast<DLLExportAttr>(Attr))
@@ -1875,7 +1871,7 @@
 }
 
 /// mergeDeclAttributes - Copy attributes from the Old decl to the New one.
-void Sema::mergeDeclAttributes(Decl *New, Decl *Old,
+void Sema::mergeDeclAttributes(NamedDecl *New, Decl *Old,
                                bool MergeDeprecation) {
   // attributes declared post-definition are currently ignored
   checkNewAttributesAfterDef(*this, New, Old);