diff --git a/include/clang/AST/Decl.h b/include/clang/AST/Decl.h
index ac7ab0f..0bf4615 100644
--- a/include/clang/AST/Decl.h
+++ b/include/clang/AST/Decl.h
@@ -221,6 +221,7 @@ public:
     Visibility visibility_;
     bool explicit_;
 
+    void setVisibility(Visibility V, bool E) { visibility_ = V; explicit_ = E; }
   public:
     LinkageInfo() : linkage_(ExternalLinkage), visibility_(DefaultVisibility),
                     explicit_(false) {}
@@ -245,8 +246,6 @@ public:
     bool visibilityExplicit() const { return explicit_; }
 
     void setLinkage(Linkage L) { linkage_ = L; }
-    void setVisibility(Visibility V, bool E) { visibility_ = V; explicit_ = E; }
-
     void mergeLinkage(Linkage L) {
       setLinkage(minLinkage(linkage(), L));
     }
@@ -259,6 +258,10 @@ public:
     // down to one of its members. If the member has no explicit visibility,
     // the class visibility wins.
     void mergeVisibility(Visibility V, bool E = false) {
+      // Never increase the visibility
+      if (visibility() < V)
+        return;
+
       // If one has explicit visibility and the other doesn't, keep the
       // explicit one.
       if (visibilityExplicit() && !E)
diff --git a/lib/AST/Decl.cpp b/lib/AST/Decl.cpp
index 53032bc..002bd2f 100644
--- a/lib/AST/Decl.cpp
+++ b/lib/AST/Decl.cpp
@@ -271,11 +271,10 @@ static LinkageInfo getLVForNamespaceScopeDecl(const NamedDecl *D, LVFlags F) {
   //   scope and no storage-class specifier, its linkage is
   //   external.
   LinkageInfo LV;
-  LV.mergeVisibility(Context.getLangOpts().getVisibilityMode());
 
   if (F.ConsiderVisibilityAttributes) {
     if (llvm::Optional<Visibility> Vis = D->getExplicitVisibility()) {
-      LV.setVisibility(*Vis, true);
+      LV.mergeVisibility(*Vis, true);
     } else {
       // If we're declared in a namespace with a visibility attribute,
       // use that namespace's visibility, but don't call it explicit.
@@ -285,13 +284,15 @@ static LinkageInfo getLVForNamespaceScopeDecl(const NamedDecl *D, LVFlags F) {
         const NamespaceDecl *ND = dyn_cast<NamespaceDecl>(DC);
         if (!ND) continue;
         if (llvm::Optional<Visibility> Vis = ND->getExplicitVisibility()) {
-          LV.setVisibility(*Vis, true);
+          LV.mergeVisibility(*Vis, true);
           break;
         }
       }
     }
   }
 
+  LV.mergeVisibility(Context.getLangOpts().getVisibilityMode());
+
   // C++ [basic.link]p4:
 
   //   A name having namespace scope has external linkage if it is the
@@ -325,11 +326,11 @@ static LinkageInfo getLVForNamespaceScopeDecl(const NamedDecl *D, LVFlags F) {
       LinkageInfo TypeLV = getLVForType(Var->getType());
       if (TypeLV.linkage() != ExternalLinkage)
         return LinkageInfo::uniqueExternal();
-      LV.mergeVisibilityWithMin(TypeLV);
+      LV.mergeVisibility(TypeLV);
     }
 
     if (Var->getStorageClass() == SC_PrivateExtern)
-      LV.setVisibility(HiddenVisibility, true);
+      LV.mergeVisibility(HiddenVisibility, true);
 
     if (!Context.getLangOpts().CPlusPlus &&
         (Var->getStorageClass() == SC_Extern ||
@@ -359,7 +360,7 @@ static LinkageInfo getLVForNamespaceScopeDecl(const NamedDecl *D, LVFlags F) {
     // just too painful to make work.
 
     if (Function->getStorageClass() == SC_PrivateExtern)
-      LV.setVisibility(HiddenVisibility, true);
+      LV.mergeVisibility(HiddenVisibility, true);
 
     // C99 6.2.2p5:
     //   If the declaration of an identifier for a function has no
@@ -482,7 +483,6 @@ static LinkageInfo getLVForClassMember(const NamedDecl *D, LVFlags F) {
     return LinkageInfo::none();
 
   LinkageInfo LV;
-  LV.mergeVisibility(D->getASTContext().getLangOpts().getVisibilityMode());
 
   bool DHasExplicitVisibility = false;
   // If we have an explicit visibility attribute, merge that in.
@@ -536,6 +536,8 @@ static LinkageInfo getLVForClassMember(const NamedDecl *D, LVFlags F) {
   if (LV.linkage() == UniqueExternalLinkage)
     return LinkageInfo::uniqueExternal();
 
+  LV.mergeVisibility(D->getASTContext().getLangOpts().getVisibilityMode());
+
   if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) {
     // If the type of the function uses a type with unique-external
     // linkage, it's not legally usable from outside this translation unit.
@@ -785,7 +787,7 @@ static LinkageInfo getLVForDecl(const NamedDecl *D, LVFlags Flags) {
       LinkageInfo LV;
       if (Flags.ConsiderVisibilityAttributes) {
         if (llvm::Optional<Visibility> Vis = Function->getExplicitVisibility())
-          LV.setVisibility(*Vis, true);
+          LV.mergeVisibility(*Vis, true);
       }
       
       if (const FunctionDecl *Prev = Function->getPreviousDecl()) {
@@ -806,10 +808,10 @@ static LinkageInfo getLVForDecl(const NamedDecl *D, LVFlags Flags) {
 
         LinkageInfo LV;
         if (Var->getStorageClass() == SC_PrivateExtern)
-          LV.setVisibility(HiddenVisibility, true);
+          LV.mergeVisibility(HiddenVisibility, true);
         else if (Flags.ConsiderVisibilityAttributes) {
           if (llvm::Optional<Visibility> Vis = Var->getExplicitVisibility())
-            LV.setVisibility(*Vis, true);
+            LV.mergeVisibility(*Vis, true);
         }
         
         if (const VarDecl *Prev = Var->getPreviousDecl()) {