diff --git a/clang/lib/AST/Decl.cpp b/clang/lib/AST/Decl.cpp
index e63560f1b6fea..3ef08cab96750 100644
--- a/clang/lib/AST/Decl.cpp
+++ b/clang/lib/AST/Decl.cpp
@@ -3251,7 +3251,6 @@ bool FunctionDecl::isGlobal() const {
     if (const auto *Namespace = cast<NamespaceDecl>(DC)) {
       if (!Namespace->getDeclName())
         return false;
-      break;
     }
   }
 
diff --git a/clang/test/SemaCXX/warn-missing-prototypes.cpp b/clang/test/SemaCXX/warn-missing-prototypes.cpp
index bb71aa8b142d1..e8637e5a90eab 100644
--- a/clang/test/SemaCXX/warn-missing-prototypes.cpp
+++ b/clang/test/SemaCXX/warn-missing-prototypes.cpp
@@ -13,6 +13,10 @@ namespace NS {
 namespace {
   // Don't warn about functions in anonymous namespaces.
   void f() { }
+  // Even if they're in nested namespaces within an anonymous namespace.
+  namespace NS {
+    void f() { }
+  }
 }
 
 struct A {