From 3f651af1ef7657ad2d2df8055d301a836ccecdfc Mon Sep 17 00:00:00 2001
From: Josh Matthews <josh@joshmatthews.net>
Date: Thu, 17 May 2018 12:24:55 -0500
Subject: [PATCH] Disable codegen-units on macOS

---
 python/servo/command_base.py | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/python/servo/command_base.py b/python/servo/command_base.py
index a200fa05f243..c273ebcf0e81 100644
--- a/python/servo/command_base.py
+++ b/python/servo/command_base.py
@@ -559,6 +559,10 @@ def package_dir(package):
             # where we want to run doctests as part of `./mach test-unit`
             env['RUSTDOC'] = path.join(self.context.topdir, 'etc', 'rustdoc-with-private')
 
+        # Workaround for https://github.com/servo/servo/issues/20756
+        if sys.platform == "darwin":
+            env['RUSTFLAGS'] = env.get('RUSTFLAGS', "") + " -C codegen-units=1"
+
         if self.config["build"]["rustflags"]:
             env['RUSTFLAGS'] = env.get('RUSTFLAGS', "") + " " + self.config["build"]["rustflags"]