From 42fc5aee6499ed6f7d1fca0d2fbac1515291b978 Mon Sep 17 00:00:00 2001
From: Mara Bos <m-ou.se@m-ou.se>
Date: Wed, 4 Jun 2025 11:54:20 +0200
Subject: [PATCH] Fix span of AddrOf in format_args!() expansion.

Diagnostics should know that the `&` for arguments in format_args!()
come from the macro expansion rather than from the original source.
---
 compiler/rustc_ast_lowering/src/format.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/compiler/rustc_ast_lowering/src/format.rs b/compiler/rustc_ast_lowering/src/format.rs
index 4138cc426c75..7a4e056175c0 100644
--- a/compiler/rustc_ast_lowering/src/format.rs
+++ b/compiler/rustc_ast_lowering/src/format.rs
@@ -489,7 +489,7 @@ fn expand_format_args<'hir>(
                 let placeholder_span =
                     placeholder_span.unwrap_or(arg.expr.span).with_ctxt(macsp.ctxt());
                 let arg = ctx.lower_expr(&arg.expr);
-                let ref_arg = ctx.arena.alloc(ctx.expr_ref(arg.span, arg));
+                let ref_arg = ctx.arena.alloc(ctx.expr_ref(arg.span.with_ctxt(macsp.ctxt()), arg));
                 make_argument(ctx, placeholder_span, ref_arg, ty)
             },
         ));