Index: clang/lib/Sema/SemaOpenMP.cpp
===================================================================
--- clang/lib/Sema/SemaOpenMP.cpp
+++ clang/lib/Sema/SemaOpenMP.cpp
@@ -17549,6 +17549,7 @@
     auto &DeclNames = SemaRef.getASTContext().DeclarationNames;
     MapperId.setName(DeclNames.getIdentifier(
         &SemaRef.getASTContext().Idents.get("default")));
+    MapperId.setLoc(StartLoc);
   }
 
   // Iterators to find the current unresolved mapper expression.
Index: clang/test/OpenMP/template-specialization.cpp
===================================================================
--- /dev/null
+++ clang/test/OpenMP/template-specialization.cpp
@@ -0,0 +1,16 @@
+// RUN: %clang_cc1 -verify -fopenmp -fsyntax-only %s
+
+// expected-no-diagnostics
+
+template <typename T>
+struct z {
+  static void aj() {
+    T f;
+#pragma omp target map(f)
+    ;
+  }
+};
+
+template <typename> class ar {};
+template <int> struct as {};
+template class z<ar<as<4>>>;