Index: lib/Sema/Sema.cpp
===================================================================
--- lib/Sema/Sema.cpp
+++ lib/Sema/Sema.cpp
@@ -470,6 +470,13 @@
     return true;
 
   if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
+    // If this is a function template, we should remove if it has no
+    // specializations.
+    if (FunctionTemplateDecl *Template = FD->getDescribedFunctionTemplate()) {
+      if (std::distance(Template->spec_begin(), Template->spec_end()))
+        return true;
+    }
+
     // UnusedFileScopedDecls stores the first declaration.
     // The declaration may have become definition so check again.
     const FunctionDecl *DeclToCheck;
Index: lib/Sema/SemaDecl.cpp
===================================================================
--- lib/Sema/SemaDecl.cpp
+++ lib/Sema/SemaDecl.cpp
@@ -1493,6 +1493,10 @@
       // 'static inline' functions are defined in headers; don't warn.
       if (FD->isInlined() && !isMainFileLoc(*this, FD->getLocation()))
         return false;
+      // 'static operator' functions are defined in headers; don't warn.
+      if (FD->isOverloadedOperator() &&
+          !isMainFileLoc(*this, FD->getLocation()))
+        return false;
     }
 
     if (FD->doesThisDeclarationHaveABody() &&
@@ -8846,6 +8850,7 @@
     if (FunctionTemplate) {
       if (NewFD->isInvalidDecl())
         FunctionTemplate->setInvalidDecl();
+      MarkUnusedFileScopedDecl(NewFD);
       return FunctionTemplate;
     }
   }
Index: lib/Serialization/ASTReader.cpp
===================================================================
--- lib/Serialization/ASTReader.cpp
+++ lib/Serialization/ASTReader.cpp
@@ -6511,12 +6511,6 @@
   return GetDecl(ID);
 }
 
-template<typename TemplateSpecializationDecl>
-static void completeRedeclChainForTemplateSpecialization(Decl *D) {
-  if (auto *TSD = dyn_cast<TemplateSpecializationDecl>(D))
-    TSD->getSpecializedTemplate()->LoadLazySpecializations();
-}
-
 void ASTReader::CompleteRedeclChain(const Decl *D) {
   if (NumCurrentElementsDeserializing) {
     // We arrange to not care about the complete redeclaration chain while we're
@@ -7136,7 +7130,7 @@
 }
 
 template<typename Key, typename ModuleFile, unsigned InitialCapacity>
-static void
+LLVM_DUMP_METHOD static void
 dumpModuleIDMap(StringRef Name,
                 const ContinuousRangeMap<Key, ModuleFile *,
                                          InitialCapacity> &Map) {
Index: test/SemaCXX/warn-unused-filescoped.cpp
===================================================================
--- test/SemaCXX/warn-unused-filescoped.cpp
+++ test/SemaCXX/warn-unused-filescoped.cpp
@@ -32,6 +32,14 @@
   inline void bar(int, int) { }
 };
 
+namespace test8 {
+// Should ignore overloaded operators.
+template <typename PT1, typename PT2>
+struct S {};
+template <typename PT1, typename PT2>
+static bool operator==(S<PT1, PT2> lhs, S<PT1, PT2> rhs) { }
+}
+
 namespace pr19713 {
 #if __cplusplus >= 201103L
   static constexpr int constexpr1() { return 1; }
@@ -200,6 +208,11 @@
 static void func() {}
 }
 
+namespace test9 {
+template<typename T>
+static void completeRedeclChainForTemplateSpecialization() { } // expected-warning {{unused}}
+}
+
 namespace pr19713 {
 #if __cplusplus >= 201103L
   // FIXME: We should warn on both of these.