From 790aaeacaea88782987c4145bc7ae47a401563f1 Mon Sep 17 00:00:00 2001
From: Andrew Kelley <superjoe30@gmail.com>
Date: Wed, 7 Mar 2018 14:35:48 -0500
Subject: add compile error for using @tagName on extern union

closes #742
---
 src/analyze.cpp | 2 ++
 1 file changed, 2 insertions(+)

(limited to 'src/analyze.cpp')

diff --git a/src/analyze.cpp b/src/analyze.cpp
index 66d2963425..74dfd003d9 100644
--- a/src/analyze.cpp
+++ b/src/analyze.cpp
@@ -2558,6 +2558,8 @@ static void resolve_union_zero_bits(CodeGen *g, TypeTableEntry *union_type) {
     HashMap<BigInt, AstNode *, bigint_hash, bigint_eql> occupied_tag_values = {};
 
     AstNode *enum_type_node = decl_node->data.container_decl.init_arg_expr;
+    union_type->data.unionation.have_explicit_tag_type = decl_node->data.container_decl.auto_enum ||
+        enum_type_node != nullptr;
     bool auto_layout = (union_type->data.unionation.layout == ContainerLayoutAuto);
     bool want_safety = (field_count >= 2) && (auto_layout || enum_type_node != nullptr);
     TypeTableEntry *tag_type;
-- 
cgit v1.2.3