Fix mishandling of deletedness for assignment operators of classes with

indirect virtual bases. We don't need to be able to invoke such an assignment
operator from the derived class, and we shouldn't delete the derived assignment
op if we can't do so.

llvm-svn: 280288

1 files changed, 4 insertions, 3 deletions

diff --git a/clang/lib/Sema/SemaDeclCXX.cpp b/clang/lib/Sema/SemaDeclCXX.cpp
index 585cd04d064..eb8c3d2cc83 100644
--- a/clang/lib/Sema/SemaDeclCXX.cpp
+++ b/clang/lib/Sema/SemaDeclCXX.cpp
@@ -6765,13 +6765,14 @@ bool Sema::ShouldDeleteSpecialMember(CXXMethodDecl *MD, CXXSpecialMember CSM,
   SpecialMemberDeletionInfo SMI(*this, MD, CSM, ICI, Diagnose);
 
   for (auto &BI : RD->bases())
-    if (!BI.isVirtual() &&
+    if ((SMI.IsAssignment || !BI.isVirtual()) &&
         SMI.shouldDeleteForBase(&BI))
       return true;
 
   // Per DR1611, do not consider virtual bases of constructors of abstract
-  // classes, since we are not going to construct them.
-  if (!RD->isAbstract() || !SMI.IsConstructor) {
+  // classes, since we are not going to construct them. For assignment
+  // operators, we only assign (and thus only consider) direct bases.
+  if ((!RD->isAbstract() || !SMI.IsConstructor) && !SMI.IsAssignment) {
     for (auto &BI : RD->vbases())
       if (SMI.shouldDeleteForBase(&BI))
         return true;