Index: lib/Sema/SemaDeclCXX.cpp
===================================================================
--- lib/Sema/SemaDeclCXX.cpp
+++ lib/Sema/SemaDeclCXX.cpp
@@ -5726,9 +5726,12 @@
         continue;
 
       if (MD->isInlined()) {
-        // MinGW does not import or export inline methods.
+        // MinGW does not import or export inline methods. But do it for
+        // template instantiations.
         if (!Context.getTargetInfo().getCXXABI().isMicrosoft() &&
-            !Context.getTargetInfo().getTriple().isWindowsItaniumEnvironment())
+            !Context.getTargetInfo().getTriple().isWindowsItaniumEnvironment() &&
+            TSK != TSK_ExplicitInstantiationDeclaration &&
+            TSK != TSK_ExplicitInstantiationDefinition)
           continue;
 
         // MSVC versions before 2015 don't export the move assignment operators
Index: test/CodeGenCXX/mingw-template-dllexport.cpp
===================================================================
--- test/CodeGenCXX/mingw-template-dllexport.cpp
+++ test/CodeGenCXX/mingw-template-dllexport.cpp
@@ -7,11 +7,9 @@
 
 template <class T>
 class c {
-  void f();
+  void f() {}
 };
 
-template <class T> void c<T>::f() {}
-
 template class __declspec(dllexport) c<int>;
 
 // CHECK: define {{.*}} dllexport {{.*}} @_ZN1cIiE1fEv