1 files changed, 23 insertions, 0 deletions
diff --git a/test/compile_errors.zig b/test/compile_errors.zig
index 6c123925da..0b9c754329 100644
--- a/test/compile_errors.zig
+++ b/test/compile_errors.zig
@@ -51,6 +51,29 @@ pub fn addCases(cases: *tests.CompileErrorContext) void {
         "tmp.zig:17:23: error: cannot adjust alignment of zero sized type 'fn(u32) anytype'",
     });
 
+    cases.addTest("invalid non-exhaustive enum to union",
+        \\const E = enum(u8) {
+        \\    a,
+        \\    b,
+        \\    _,
+        \\};
+        \\const U = union(E) {
+        \\    a,
+        \\    b,
+        \\};
+        \\export fn foo() void {
+        \\    var e = @intToEnum(E, 15);
+        \\    var u: U = e;
+        \\}
+        \\export fn bar() void {
+        \\    const e = @intToEnum(E, 15);
+        \\    var u: U = e;
+        \\}
+    , &[_][]const u8{
+        "tmp.zig:12:16: error: runtime cast to union 'U' from non-exhustive enum",
+        "tmp.zig:16:16: error: no tag by value 15",
+    });
+
     cases.addTest("switching with exhaustive enum has '_' prong ",
         \\const E = enum{
         \\    a,