Re-land "[MS] Don't expect vftables to be provided for extern template instantiations"
Reverts r273305 and re-instates r273296.
We needed to fix a bug in Sema::MarkVTableUsed to ensure that operator
delete lookup occurs when the vtable is referenced. We already had a
special case to look up operator delete when dllimport was used, but I
think should really mark virtual destructors referenced any time the
vtable is used.
llvm-svn: 274147
diff --git a/clang/lib/CodeGen/CGVTables.cpp b/clang/lib/CodeGen/CGVTables.cpp
index 83974e0..9570550 100644
--- a/clang/lib/CodeGen/CGVTables.cpp
+++ b/clang/lib/CodeGen/CGVTables.cpp
@@ -794,6 +794,10 @@
return DiscardableODRLinkage;
case TSK_ExplicitInstantiationDeclaration:
+ // Explicit instantiations in MSVC do not provide vtables, so we must emit
+ // our own.
+ if (getTarget().getCXXABI().isMicrosoft())
+ return DiscardableODRLinkage;
return shouldEmitAvailableExternallyVTable(*this, RD)
? llvm::GlobalVariable::AvailableExternallyLinkage
: llvm::GlobalVariable::ExternalLinkage;
@@ -839,9 +843,9 @@
bool CodeGenVTables::isVTableExternal(const CXXRecordDecl *RD) {
assert(RD->isDynamicClass() && "Non-dynamic classes have no VTable.");
- // We always synthesize vtables on the import side regardless of whether or
- // not it is an explicit instantiation declaration.
- if (CGM.getTarget().getCXXABI().isMicrosoft() && RD->hasAttr<DLLImportAttr>())
+ // We always synthesize vtables if they are needed in the MS ABI. MSVC doesn't
+ // emit them even if there is an explicit template instantiation.
+ if (CGM.getTarget().getCXXABI().isMicrosoft())
return false;
// If we have an explicit instantiation declaration (and not a