diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -3562,7 +3562,14 @@
       }
     }
 
-    if (OldQTypeForComparison == NewQType)
+    if (OldQTypeForComparison == NewQType ||
+        // In Microsoft compatibility mode, the intent is to only warn on
+        // mismatched exception specifiers.  By this point, that warning has
+        // already been issued, so we should treat mismatches only in exception
+        // specifier as equivalent.
+        (getLangOpts().MSVCCompat &&
+         Context.hasSameFunctionTypeIgnoringExceptionSpec(OldQTypeForComparison,
+                                                          NewQType)))
       return MergeCompatibleFunctionDecls(New, Old, S, MergeTypeWithOld);
 
     // If the types are imprecise (due to dependent constructs in friends or
diff --git a/clang/test/SemaCXX/ms-exception-spec.cpp b/clang/test/SemaCXX/ms-exception-spec.cpp
--- a/clang/test/SemaCXX/ms-exception-spec.cpp
+++ b/clang/test/SemaCXX/ms-exception-spec.cpp
@@ -1,4 +1,5 @@
-// RUN: %clang_cc1 %s -fsyntax-only -verify -fms-compatibility -fexceptions -fcxx-exceptions
+// RUN: %clang_cc1 -std=c++11 %s -fsyntax-only -verify -fms-compatibility -fexceptions -fcxx-exceptions
+// RUN: %clang_cc1 -std=c++17 %s -fsyntax-only -verify -fms-compatibility -fexceptions -fcxx-exceptions
 
 void f() throw(...) { }
 
@@ -7,3 +8,11 @@
 void fn() throw(S); // expected-warning {{incomplete type}} expected-note{{previous declaration}}
 void fn() throw();  // expected-warning {{does not match previous declaration}}
 }
+
+template <typename T> struct FooPtr {
+  template <typename U> FooPtr(U *p) : m_pT(nullptr) {}
+  template <> FooPtr(T *pInterface) throw() : m_pT(pInterface) {}  // expected-warning {{exception specification in declaration does not match previous declaration}}
+  T *m_pT;
+};
+struct Bar {};
+template struct FooPtr<Bar>;