From 592f1043dc704faf79bde7149917d4155b3747f8 Mon Sep 17 00:00:00 2001
From: Jacob Young <jacobly0@users.noreply.github.com>
Date: Sat, 19 Jul 2025 13:54:31 -0400
Subject: [PATCH] cbe: fix comptime-known packed unions

---
 src/codegen/c.zig | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/codegen/c.zig b/src/codegen/c.zig
index 955a83bc33..c726c05e1b 100644
--- a/src/codegen/c.zig
+++ b/src/codegen/c.zig
@@ -2438,7 +2438,10 @@ pub const DeclGen = struct {
         const ty = val.typeOf(zcu);
         return .{ .data = .{
             .dg = dg,
-            .int_info = ty.intInfo(zcu),
+            .int_info = if (ty.zigTypeTag(zcu) == .@"union" and ty.containerLayout(zcu) == .@"packed")
+                .{ .signedness = .unsigned, .bits = @intCast(ty.bitSize(zcu)) }
+            else
+                ty.intInfo(zcu),
             .kind = kind,
             .ctype = try dg.ctypeFromType(ty, kind),
             .val = val,