2 files changed, 48 insertions, 6 deletions
diff --git a/lib/Sema/SemaDeclAttr.cpp b/lib/Sema/SemaDeclAttr.cpp
index 3e0fa53041..829bc9a104 100644
--- a/lib/Sema/SemaDeclAttr.cpp
+++ b/lib/Sema/SemaDeclAttr.cpp
@@ -5694,18 +5694,18 @@ static void handleLayoutVersion(Sema &S, Decl *D, const ParsedAttr &AL) {
   if (!checkUInt32Argument(S, AL, AL.getArgAsExpr(0), Version))
     return;
 
-  // The attribute expects a "major" version number like 19, but new versions of
-  // MSVC have moved to updating the "minor", or less significant numbers, so we
-  // have to multiply by 100 now.
-  Version *= 100;
-
   // TODO: Investigate what happens with the next major version of MSVC.
-  if (Version != LangOptions::MSVC2015) {
+  if (Version != LangOptions::MSVC2015 / 100) {
     S.Diag(AL.getLoc(), diag::err_attribute_argument_out_of_bounds)
         << AL << Version << VersionExpr->getSourceRange();
     return;
   }
 
+  // The attribute expects a "major" version number like 19, but new versions of
+  // MSVC have moved to updating the "minor", or less significant numbers, so we
+  // have to multiply by 100 now.
+  Version *= 100;
+
   D->addAttr(::new (S.Context)
                  LayoutVersionAttr(AL.getRange(), S.Context, Version,
                                    AL.getAttributeSpellingListIndex()));
diff --git a/test/CodeGenCXX/mangle-ms-exception-spec.cpp b/test/CodeGenCXX/mangle-ms-exception-spec.cpp
new file mode 100644
index 0000000000..1aaf2486ea
--- /dev/null
+++ b/test/CodeGenCXX/mangle-ms-exception-spec.cpp
@@ -0,0 +1,42 @@
+// RUN: %clang_cc1 -std=c++11 -fms-extensions -emit-llvm %s -o - -triple=x86_64-pc-win32 -Wno-noexcept-type -fms-compatibility-version=19.12 | FileCheck %s --check-prefix=CHECK --check-prefix=CXX11
+// RUN: %clang_cc1 -std=c++17 -fms-extensions -emit-llvm %s -o - -triple=x86_64-pc-win32 | FileCheck %s --check-prefix=CHECK --check-prefix=NOCOMPAT
+// RUN: %clang_cc1 -std=c++17 -fms-extensions -emit-llvm %s -o - -triple=x86_64-pc-win32 -fms-compatibility-version=19.12 | FileCheck %s --check-prefix=CHECK --check-prefix=CXX17
+
+// Prove that mangling only changed for noexcept types under /std:C++17, not all noexcept functions
+// CHECK-DAG: @"?nochange@@YAXXZ"
+void nochange() noexcept {}
+
+// CXX11-DAG: @"?a@@YAXP6AHXZ@Z"
+// NOCOMPAT-DAG: @"?a@@YAXP6AHXZ@Z"
+// CXX17-DAG: @"?a@@YAXP6AHX_E@Z"
+void a(int() noexcept) {}
+// CHECK-DAG: @"?b@@YAXP6AHXZ@Z"
+void b(int() noexcept(false)) {}
+// CXX11-DAG: @"?c@@YAXP6AHXZ@Z"
+// NOCOMPAT-DAG: @"?c@@YAXP6AHXZ@Z"
+// CXX17-DAG: @"?c@@YAXP6AHX_E@Z"
+void c(int() noexcept(true)) {}
+// CHECK-DAG: @"?d@@YAXP6AHXZ@Z"
+void d(int()) {}
+
+template <typename T>
+class e;
+template <typename T, typename... U>
+class e<T(U...) noexcept> {
+  // CXX11-DAG: @"?ee@?$e@$$A6AXXZ@@EEAAXXZ"
+  // NOCOMPAT-DAG: @"?ee@?$e@$$A6AXXZ@@EEAAXXZ"
+  // CXX17-DAG: @"?ee@?$e@$$A6AXX_E@@EEAAXXZ"
+  virtual T ee(U &&...) noexcept {};
+};
+
+e<void() noexcept> e1;
+
+template <typename T>
+class f;
+template <typename T, typename... U>
+class f<T(U...)> {
+  // CHECK-DAG: @"?ff@?$f@$$A6AXXZ@@EEAAXXZ"
+  virtual T ff(U &&...) noexcept {};
+};
+
+f<void()> f1;