Implement codegen for MSVC unions with reference members.
Currently, clang accepts a union with a reference member when given the -fms-extensions flag. This change fixes the codegen for this case.
Patch by Dominic Ferreira.
llvm-svn: 370052
diff --git a/clang/lib/CodeGen/CGExpr.cpp b/clang/lib/CodeGen/CGExpr.cpp
index 86ef0b8..6cabfcc 100644
--- a/clang/lib/CodeGen/CGExpr.cpp
+++ b/clang/lib/CodeGen/CGExpr.cpp
@@ -4056,7 +4056,6 @@
unsigned RecordCVR = base.getVRQualifiers();
if (rec->isUnion()) {
// For unions, there is no pointer adjustment.
- assert(!FieldType->isReferenceType() && "union has reference member");
if (CGM.getCodeGenOpts().StrictVTablePointers &&
hasAnyVptr(FieldType, getContext()))
// Because unions can easily skip invariant.barriers, we need to add
@@ -4073,27 +4072,30 @@
addr.getPointer(), getDebugInfoFIndex(rec, field->getFieldIndex()), DbgInfo),
addr.getAlignment());
}
- } else {
+ if (FieldType->isReferenceType())
+ addr = Builder.CreateElementBitCast(
+ addr, CGM.getTypes().ConvertTypeForMem(FieldType), field->getName());
+ } else {
if (!IsInPreservedAIRegion)
// For structs, we GEP to the field that the record layout suggests.
addr = emitAddrOfFieldStorage(*this, addr, field);
else
// Remember the original struct field index
addr = emitPreserveStructAccess(*this, addr, field);
+ }
- // If this is a reference field, load the reference right now.
- if (FieldType->isReferenceType()) {
- LValue RefLVal = MakeAddrLValue(addr, FieldType, FieldBaseInfo,
- FieldTBAAInfo);
- if (RecordCVR & Qualifiers::Volatile)
- RefLVal.getQuals().addVolatile();
- addr = EmitLoadOfReference(RefLVal, &FieldBaseInfo, &FieldTBAAInfo);
+ // If this is a reference field, load the reference right now.
+ if (FieldType->isReferenceType()) {
+ LValue RefLVal =
+ MakeAddrLValue(addr, FieldType, FieldBaseInfo, FieldTBAAInfo);
+ if (RecordCVR & Qualifiers::Volatile)
+ RefLVal.getQuals().addVolatile();
+ addr = EmitLoadOfReference(RefLVal, &FieldBaseInfo, &FieldTBAAInfo);
- // Qualifiers on the struct don't apply to the referencee.
- RecordCVR = 0;
- FieldType = FieldType->getPointeeType();
- }
+ // Qualifiers on the struct don't apply to the referencee.
+ RecordCVR = 0;
+ FieldType = FieldType->getPointeeType();
}
// Make sure that the address is pointing to the right type. This is critical