diff --git a/clang/include/clang/Basic/Attr.td b/clang/include/clang/Basic/Attr.td
--- a/clang/include/clang/Basic/Attr.td
+++ b/clang/include/clang/Basic/Attr.td
@@ -569,9 +569,6 @@
   list<Accessor> Accessors = [];
   // Set to true for attributes with arguments which require delayed parsing.
   bit LateParsed = 0;
-  // Set to false to prevent an attribute from being propagated from a template
-  // to the instantiation.
-  bit Clone = 1;
   // Set to true for attributes which must be instantiated within templates
   bit TemplateDependent = 0;
   // Set to true for attributes that have a corresponding AST node.
@@ -3027,7 +3024,6 @@
 }
 
 def Visibility : InheritableAttr {
-  let Clone = 0;
   let Spellings = [GCC<"visibility">];
   let Args = [EnumArgument<"Visibility", "VisibilityType",
                            ["default", "hidden", "internal", "protected"],
@@ -3037,7 +3033,6 @@
 }
 
 def TypeVisibility : InheritableAttr {
-  let Clone = 0;
   let Spellings = [Clang<"type_visibility">];
   let Args = [EnumArgument<"Visibility", "VisibilityType",
                            ["default", "hidden", "internal", "protected"],
diff --git a/clang/lib/Sema/SemaDeclAttr.cpp b/clang/lib/Sema/SemaDeclAttr.cpp
--- a/clang/lib/Sema/SemaDeclAttr.cpp
+++ b/clang/lib/Sema/SemaDeclAttr.cpp
@@ -2885,9 +2885,11 @@
     typename T::VisibilityType existingValue = existingAttr->getVisibility();
     if (existingValue == value)
       return nullptr;
-    S.Diag(existingAttr->getLocation(), diag::err_mismatched_visibility);
-    S.Diag(CI.getLoc(), diag::note_previous_attribute);
     D->dropAttr<T>();
+    if (!existingAttr->isImplicit()) {
+      S.Diag(existingAttr->getLocation(), diag::err_mismatched_visibility);
+      S.Diag(CI.getLoc(), diag::note_previous_attribute);
+    }
   }
   return ::new (S.Context) T(S.Context, CI, value);
 }
diff --git a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
--- a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
+++ b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
@@ -815,6 +815,18 @@
       continue;
     }
 
+    if (auto *A = dyn_cast<VisibilityAttr>(TmplAttr)) {
+      if (isa<FunctionDecl>(Tmpl) && !New->hasAttr<VisibilityAttr>()) {
+        auto *NewA = A->clone(Context);
+        NewA->setImplicit(true);
+        New->addAttr(NewA);
+      }
+      continue;
+    }
+
+    if (auto *A = dyn_cast<TypeVisibilityAttr>(TmplAttr))
+      continue;
+
     assert(!TmplAttr->isPackExpansion());
     if (TmplAttr->isLateParsed() && LateAttrs) {
       // Late parsed attributes must be instantiated and attached after the
diff --git a/clang/test/CodeGenCXX/visibility.cpp b/clang/test/CodeGenCXX/visibility.cpp
--- a/clang/test/CodeGenCXX/visibility.cpp
+++ b/clang/test/CodeGenCXX/visibility.cpp
@@ -1017,8 +1017,8 @@
   void DEFAULT zed() {
   }
   template void zed<&da>();
-  // CHECK-LABEL: define weak_odr hidden void @_ZN6test513zedIXadL_ZNS_2daEEEEEvv(
-  // CHECK-HIDDEN-LABEL: define weak_odr hidden void @_ZN6test513zedIXadL_ZNS_2daEEEEEvv(
+  // CHECK-LABEL: define weak_odr void @_ZN6test513zedIXadL_ZNS_2daEEEEEvv(
+  // CHECK-HIDDEN-LABEL: define weak_odr void @_ZN6test513zedIXadL_ZNS_2daEEEEEvv(
 
   template void DEFAULT zed<&db>();
   // CHECK-LABEL: define weak_odr void @_ZN6test513zedIXadL_ZNS_2dbEEEEEvv(
@@ -1029,8 +1029,8 @@
   // CHECK-HIDDEN-LABEL: define weak_odr hidden void @_ZN6test513zedIXadL_ZNS_2dcEEEEEvv(
 
   template void zed<&ha>();
-  // CHECK-LABEL: define weak_odr hidden void @_ZN6test513zedIXadL_ZNS_2haEEEEEvv(
-  // CHECK-HIDDEN-LABEL: define weak_odr hidden void @_ZN6test513zedIXadL_ZNS_2haEEEEEvv(
+  // CHECK-LABEL: define weak_odr void @_ZN6test513zedIXadL_ZNS_2haEEEEEvv(
+  // CHECK-HIDDEN-LABEL: define weak_odr void @_ZN6test513zedIXadL_ZNS_2haEEEEEvv(
 
   template void DEFAULT zed<&hb>();
   // CHECK-LABEL: define weak_odr void @_ZN6test513zedIXadL_ZNS_2hbEEEEEvv(
@@ -1429,6 +1429,7 @@
   template <class T> template <class U>
   U foo<T>::bar() { return {}; }
 
+  /// foo<int>::{zed,bar} get the instantiated-from member's HIDDEN, overriding DEFAULT.
   extern template struct DEFAULT foo<int>;
 
   int use() {
@@ -1436,13 +1437,12 @@
     foo<long> p;
     return o.zed() + o.bar<int>() + p.zed() + p.bar<int>();
   }
-  /// FIXME: foo<int>::bar is hidden in GCC w/ or w/o -fvisibility=hidden.
   // CHECK-LABEL: declare hidden noundef i32 @_ZN6test713fooIiE3zedEv(
-  // CHECK-LABEL: define linkonce_odr noundef i32 @_ZN6test713fooIiE3barIiEET_v(
+  // CHECK-LABEL: define linkonce_odr hidden noundef i32 @_ZN6test713fooIiE3barIiEET_v(
   // CHECK-LABEL: define linkonce_odr hidden noundef i64 @_ZN6test713fooIlE3zedEv(
-  // CHECK-LABEL: define linkonce_odr noundef i32 @_ZN6test713fooIlE3barIiEET_v(
+  // CHECK-LABEL: define linkonce_odr hidden noundef i32 @_ZN6test713fooIlE3barIiEET_v(
   // CHECK-HIDDEN-LABEL: declare hidden noundef i32 @_ZN6test713fooIiE3zedEv(
-  // CHECK-HIDDEN-LABEL: define linkonce_odr noundef i32 @_ZN6test713fooIiE3barIiEET_v(
+  // CHECK-HIDDEN-LABEL: define linkonce_odr hidden noundef i32 @_ZN6test713fooIiE3barIiEET_v(
   // CHECK-HIDDEN-LABEL: define linkonce_odr hidden noundef i64 @_ZN6test713fooIlE3zedEv(
   // CHECK-HIDDEN-LABEL: define linkonce_odr hidden noundef i32 @_ZN6test713fooIlE3barIiEET_v(
 }
diff --git a/clang/utils/TableGen/ClangAttrEmitter.cpp b/clang/utils/TableGen/ClangAttrEmitter.cpp
--- a/clang/utils/TableGen/ClangAttrEmitter.cpp
+++ b/clang/utils/TableGen/ClangAttrEmitter.cpp
@@ -3667,8 +3667,7 @@
     if (!R.getValueAsBit("ASTNode"))
       continue;
     OS << "    case attr::" << R.getName() << ": {\n";
-    bool ShouldClone = R.getValueAsBit("Clone") &&
-                       (!AppliesToDecl ||
+    bool ShouldClone = (!AppliesToDecl ||
                         R.getValueAsBit("MeaningfulToClassTemplateDefinition"));
 
     if (!ShouldClone) {