Implement semantic analysis for transparent unions. This is largely
based on a patch from Anders Johnsen. CodeGen support is incomplete,
in that we do not properly coerce to the first field's type.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@70419 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaOverload.cpp b/lib/Sema/SemaOverload.cpp
index f4b6598..ab66939 100644
--- a/lib/Sema/SemaOverload.cpp
+++ b/lib/Sema/SemaOverload.cpp
@@ -1888,9 +1888,13 @@
if (!getLangOptions().CPlusPlus) {
// In C, argument passing is the same as performing an assignment.
QualType FromType = From->getType();
+
AssignConvertType ConvTy =
CheckSingleAssignmentConstraints(ToType, From);
-
+ if (ConvTy != Compatible &&
+ CheckTransparentUnionArgumentConstraints(ToType, From) == Compatible)
+ ConvTy = Compatible;
+
return DiagnoseAssignmentResult(ConvTy, From->getLocStart(), ToType,
FromType, From, Flavor);
}