Correctly propagate the storage class to function template instantiations.

This fixes pr15753. This is another case of the fuzzy definition of the
"as written" storage class of an instantiation.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@179581 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Sema/SemaTemplateInstantiateDecl.cpp

@@ -1162,7 +1162,7 @@ Decl *TemplateDeclInstantiator::VisitFunctionDecl(FunctionDecl *D,
   FunctionDecl *Function =
       FunctionDecl::Create(SemaRef.Context, DC, D->getInnerLocStart(),
                            D->getNameInfo(), T, TInfo,
-                           D->getStorageClass(),
+                           D->getCanonicalDecl()->getStorageClass(),
                            D->isInlineSpecified(), D->hasWrittenPrototype(),
                            D->isConstexpr());
 

test/CodeGenCXX/pr15753.cpp

@@ -0,0 +1,12 @@
+// RUN: %clang_cc1 -emit-llvm %s -o - | FileCheck %s
+
+template <typename T> static int Foo(T t);
+template <typename T>
+int Foo(T t) {
+  return t;
+}
+template<> int Foo<int>(int i) {
+  return i;
+}
+
+// CHECK-NOT: define