From 66bfcb3ea59437b83a15cfe47413b7dc3c9714ee Mon Sep 17 00:00:00 2001
From: Peter Collingbourne <peter@pcc.me.uk>
Date: Sat, 19 Nov 2016 00:30:56 +0000
Subject: [PATCH] Sema: As of MSVC 2015, a user-declared move operation causes
 the deletion of both copy operations.

Differential Revision: https://reviews.llvm.org/D26868

llvm-svn: 287411
---
 clang/lib/Sema/SemaDeclCXX.cpp                | 13 +++++++++----
 clang/test/SemaCXX/MicrosoftCompatibility.cpp | 16 ++++++++++++++++
 2 files changed, 25 insertions(+), 4 deletions(-)

diff --git a/clang/lib/Sema/SemaDeclCXX.cpp b/clang/lib/Sema/SemaDeclCXX.cpp
index d41748f..82da95e 100644
--- a/clang/lib/Sema/SemaDeclCXX.cpp
+++ b/clang/lib/Sema/SemaDeclCXX.cpp
@@ -6711,10 +6711,15 @@ bool Sema::ShouldDeleteSpecialMember(CXXMethodDecl *MD, CXXSpecialMember CSM,
       (CSM == CXXCopyConstructor || CSM == CXXCopyAssignment)) {
     CXXMethodDecl *UserDeclaredMove = nullptr;
 
-    // In Microsoft mode, a user-declared move only causes the deletion of the
-    // corresponding copy operation, not both copy operations.
+    // In Microsoft mode up to MSVC 2013, a user-declared move only causes the
+    // deletion of the corresponding copy operation, not both copy operations.
+    // MSVC 2015 has adopted the standards conforming behavior.
+    bool DeletesOnlyMatchingCopy =
+        getLangOpts().MSVCCompat &&
+        !getLangOpts().isCompatibleWithMSVC(LangOptions::MSVC2015);
+
     if (RD->hasUserDeclaredMoveConstructor() &&
-        (!getLangOpts().MSVCCompat || CSM == CXXCopyConstructor)) {
+        (!DeletesOnlyMatchingCopy || CSM == CXXCopyConstructor)) {
       if (!Diagnose) return true;
 
       // Find any user-declared move constructor.
@@ -6726,7 +6731,7 @@ bool Sema::ShouldDeleteSpecialMember(CXXMethodDecl *MD, CXXSpecialMember CSM,
       }
       assert(UserDeclaredMove);
     } else if (RD->hasUserDeclaredMoveAssignment() &&
-               (!getLangOpts().MSVCCompat || CSM == CXXCopyAssignment)) {
+               (!DeletesOnlyMatchingCopy || CSM == CXXCopyAssignment)) {
       if (!Diagnose) return true;
 
       // Find any user-declared move assignment operator.
diff --git a/clang/test/SemaCXX/MicrosoftCompatibility.cpp b/clang/test/SemaCXX/MicrosoftCompatibility.cpp
index 5660868..26cd782 100644
--- a/clang/test/SemaCXX/MicrosoftCompatibility.cpp
+++ b/clang/test/SemaCXX/MicrosoftCompatibility.cpp
@@ -99,23 +99,39 @@ int jump_over_indirect_goto() {
 namespace PR11826 {
   struct pair {
     pair(int v) { }
+#if _MSC_VER >= 1900
+    void operator=(pair&& rhs) { } // expected-note {{copy constructor is implicitly deleted because 'pair' has a user-declared move assignment operator}}
+#else
     void operator=(pair&& rhs) { }
+#endif
   };
   void f() {
     pair p0(3);
+#if _MSC_VER >= 1900
+    pair p = p0; // expected-error {{call to implicitly-deleted copy constructor of 'PR11826::pair'}}
+#else
     pair p = p0;
+#endif
   }
 }
 
 namespace PR11826_for_symmetry {
   struct pair {
     pair(int v) { }
+#if _MSC_VER >= 1900
+    pair(pair&& rhs) { } // expected-note {{copy assignment operator is implicitly deleted because 'pair' has a user-declared move constructor}}
+#else
     pair(pair&& rhs) { }
+#endif
   };
   void f() {
     pair p0(3);
     pair p(4);
+#if _MSC_VER >= 1900
+    p = p0; // expected-error {{object of type 'PR11826_for_symmetry::pair' cannot be assigned because its copy assignment operator is implicitly deleted}}
+#else
     p = p0;
+#endif
   }
 }
 
-- 
2.7.4