From 4d2766e3524129f0d7ec6ad34c4045150ad4f978 Mon Sep 17 00:00:00 2001
From: bjorn3 <bjorn3@users.noreply.github.com>
Date: Mon, 25 Jan 2021 18:48:49 +0100
Subject: [PATCH] Fix abi for wasm-bindgen

---
 compiler/rustc_middle/src/ty/layout.rs | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/compiler/rustc_middle/src/ty/layout.rs b/compiler/rustc_middle/src/ty/layout.rs
index ef467ed65145..a6b7b3932136 100644
--- a/compiler/rustc_middle/src/ty/layout.rs
+++ b/compiler/rustc_middle/src/ty/layout.rs
@@ -2752,6 +2752,14 @@ where
                 attrs
             });
 
+            if target.arch == "wasm32" && target.os == "unknown" {
+                // wasm-bindgen depends on ABI details and is incompatible with the
+                // correct C ABI, so this is being kept around until wasm-bindgen
+                // can be fixed to work with the correct ABI. See #63649 for further
+                // discussion.
+                arg.mode = PassMode::Direct(ArgAttributes::new());
+            }
+
             if arg.layout.is_zst() {
                 // For some forsaken reason, x86_64-pc-windows-gnu
                 // doesn't ignore zero-sized struct arguments.