From 4068fafcc621a05f4149f5e838c938f78c9500ad Mon Sep 17 00:00:00 2001
From: Jacob Young <jacobly0@users.noreply.github.com>
Date: Sat, 24 Dec 2022 19:44:52 -0500
Subject: [PATCH] Sema: fix missing struct layout for llvm backend

Closes #14063
---
 src/Sema.zig             | 12 ++++++++++++
 test/behavior/struct.zig | 13 +++++++++++++
 2 files changed, 25 insertions(+)

diff --git a/src/Sema.zig b/src/Sema.zig
index fab94a06ff..bc13e9bd0f 100644
--- a/src/Sema.zig
+++ b/src/Sema.zig
@@ -29155,6 +29155,18 @@ pub fn resolveTypeLayout(sema: *Sema, ty: Type) CompileError!void {
             const payload_ty = ty.errorUnionPayload();
             return sema.resolveTypeLayout(payload_ty);
         },
+        .Fn => {
+            const info = ty.fnInfo();
+            if (info.is_generic) {
+                // Resolving of generic function types is defeerred to when
+                // the function is instantiated.
+                return;
+            }
+            for (info.param_types) |param_ty| {
+                try sema.resolveTypeLayout(param_ty);
+            }
+            try sema.resolveTypeLayout(info.return_type);
+        },
         else => {},
     }
 }
diff --git a/test/behavior/struct.zig b/test/behavior/struct.zig
index cce9654254..2a15d68c67 100644
--- a/test/behavior/struct.zig
+++ b/test/behavior/struct.zig
@@ -1430,3 +1430,16 @@ test "struct field has a pointer to an aligned version of itself" {
 
     try expect(&e == e.next);
 }
+
+test "struct only referenced from optional parameter/return" {
+    const S = struct {
+        fn f(_: ?struct { x: u8 }) void {}
+        fn g() ?struct { x: u8 } {
+            return null;
+        }
+    };
+
+    const fp: *const anyopaque = &S.f;
+    const gp: *const anyopaque = &S.g;
+    try expect(fp != gp);
+}