From 61e24e630d5eea7bbff63e46051de509ceb46c33 Mon Sep 17 00:00:00 2001
From: Ralf Jung <post@ralfj.de>
Date: Sat, 22 Mar 2025 18:42:01 +0100
Subject: [PATCH] allow wasm_c_abi in proc_macro bridge

---
 library/proc_macro/src/bridge/mod.rs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/library/proc_macro/src/bridge/mod.rs b/library/proc_macro/src/bridge/mod.rs
index 03c3e697cfe2..52cc8fba0438 100644
--- a/library/proc_macro/src/bridge/mod.rs
+++ b/library/proc_macro/src/bridge/mod.rs
@@ -7,6 +7,10 @@
 //! Rust ABIs (e.g., stage0/bin/rustc vs stage1/bin/rustc during bootstrap).
 
 #![deny(unsafe_code)]
+// proc_macros anyway don't work on wasm hosts so while both sides of this bridge can
+// be built with different versions of rustc, the wasm ABI changes don't really matter.
+#![cfg_attr(bootstrap, allow(unknown_lints))]
+#![allow(wasm_c_abi)]
 
 use std::hash::Hash;
 use std::ops::{Bound, Range};