llvm: ensure returned undef is 0xaa bytes when runtime safety is enabled

Closes #13178

1 files changed, 22 insertions, 0 deletions

diff --git a/test/behavior/undefined.zig b/test/behavior/undefined.zig
index b26002e080..a093ce669e 100644
--- a/test/behavior/undefined.zig
+++ b/test/behavior/undefined.zig
@@ -97,3 +97,25 @@ test "reslice of undefined global var slice" {
     const x = buf[0..1];
     try @import("std").testing.expect(x.len == 1 and x[0] == 0);
 }
+
+test "returned undef is 0xaa bytes when runtime safety is enabled" {
+    if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; // TODO
+    if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
+
+    const Rect = struct {
+        x: f32,
+        fn getUndefStruct() @This() {
+            @setRuntimeSafety(true);
+            return undefined;
+        }
+        fn getUndefInt() u32 {
+            @setRuntimeSafety(true);
+            return undefined;
+        }
+    };
+    try std.testing.expect(@as(u32, @bitCast(Rect.getUndefStruct().x)) == 0xAAAAAAAA);
+    try std.testing.expect(Rect.getUndefInt() == 0xAAAAAAAA);
+}