add codegen support to union casts
init of static vars still not working. I'll get back to it tomorrow or so
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@62278 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGExprAgg.cpp b/lib/CodeGen/CGExprAgg.cpp
index 7571149..5e36751 100644
--- a/lib/CodeGen/CGExprAgg.cpp
+++ b/lib/CodeGen/CGExprAgg.cpp
@@ -74,6 +74,7 @@
// Operators.
// case Expr::UnaryOperatorClass:
// case Expr::CastExprClass:
+ void VisitCStyleCastExpr(CStyleCastExpr *E);
void VisitImplicitCastExpr(ImplicitCastExpr *E);
void VisitCallExpr(const CallExpr *E);
void VisitStmtExpr(const StmtExpr *E);
@@ -127,6 +128,18 @@
// Visitor Methods
//===----------------------------------------------------------------------===//
+void AggExprEmitter::VisitCStyleCastExpr(CStyleCastExpr *E) {
+ // GCC union extension
+ if (E->getType()->isUnionType()) {
+ RecordDecl *SD = E->getType()->getAsRecordType()->getDecl();
+ LValue FieldLoc = CGF.EmitLValueForField(DestPtr, *SD->field_begin(), true, 0);
+ EmitInitializationToLValue(E->getSubExpr(), FieldLoc);
+ return;
+ }
+
+ Visit(E->getSubExpr());
+}
+
void AggExprEmitter::VisitImplicitCastExpr(ImplicitCastExpr *E) {
assert(CGF.getContext().typesAreCompatible(
E->getSubExpr()->getType().getUnqualifiedType(),
@@ -467,7 +480,7 @@
// Unions only initialize one field.
// (things can get weird with designators, but they aren't
// supported yet.)
- if (E->getType()->isUnionType())
+ if (isUnion)
break;
}
}
diff --git a/test/CodeGen/cast-to-union.c b/test/CodeGen/cast-to-union.c
new file mode 100644
index 0000000..3f33904
--- /dev/null
+++ b/test/CodeGen/cast-to-union.c
@@ -0,0 +1,10 @@
+// RUN: clang -emit-llvm < %s | grep "store i32 351, i32*"
+
+union u { int i; };
+
+void foo() {
+ union u ola = (union u) 351;
+}
+
+// FIXME: not working yet
+// union u w = (union u)2;