Mark virtual methods that are used in tables included in VTTs as used.

Fixes PR6706.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@99582 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 19 insertions, 2 deletions

diff --git a/lib/Sema/Sema.h b/lib/Sema/Sema.h
index 5986b479cd..2ccc41f287 100644
--- a/lib/Sema/Sema.h
+++ b/lib/Sema/Sema.h
@@ -2486,7 +2486,8 @@ public:
   
   /// MarkVirtualMembersReferenced - Will mark all virtual members of the given
   /// CXXRecordDecl referenced.
-  void MarkVirtualMembersReferenced(SourceLocation Loc, CXXRecordDecl *RD);
+  void MarkVirtualMembersReferenced(SourceLocation Loc,
+                                    const CXXRecordDecl *RD);
 
   /// ProcessPendingClassesWithUnmarkedVirtualMembers - Will process classes 
   /// that might need to have their virtual members marked as referenced.
diff --git a/lib/Sema/SemaDeclCXX.cpp b/lib/Sema/SemaDeclCXX.cpp
index 9a68f472e6..1f6630e343 100644
--- a/lib/Sema/SemaDeclCXX.cpp
+++ b/lib/Sema/SemaDeclCXX.cpp
@@ -5944,7 +5944,8 @@ bool Sema::ProcessPendingClassesWithUnmarkedVirtualMembers() {
   return true;
 }
 
-void Sema::MarkVirtualMembersReferenced(SourceLocation Loc, CXXRecordDecl *RD) {
+void Sema::MarkVirtualMembersReferenced(SourceLocation Loc,
+                                        const CXXRecordDecl *RD) {
   for (CXXRecordDecl::method_iterator i = RD->method_begin(), 
        e = RD->method_end(); i != e; ++i) {
     CXXMethodDecl *MD = *i;
@@ -5954,4 +5955,19 @@ void Sema::MarkVirtualMembersReferenced(SourceLocation Loc, CXXRecordDecl *RD) {
     if (MD->isVirtual() && !MD->isPure())
       MarkDeclarationReferenced(Loc, MD);
   }
+
+  // Only classes that have virtual bases need a VTT.
+  if (RD->getNumVBases() == 0)
+    return;
+
+  for (CXXRecordDecl::base_class_const_iterator i = RD->bases_begin(),
+           e = RD->bases_end(); i != e; ++i) {
+    const CXXRecordDecl *Base =
+        cast<CXXRecordDecl>(i->getType()->getAs<RecordType>()->getDecl());
+    if (i->isVirtual())
+      continue;
+    if (Base->getNumVBases() == 0)
+      continue;
+    MarkVirtualMembersReferenced(Loc, Base);
+  }
 }