From 7c92361028555ea0fcb0da0a8ce059e52ee4d1a8 Mon Sep 17 00:00:00 2001
From: Aaron Janse <aaron@ajanse.me>
Date: Sat, 17 Oct 2020 00:47:14 -0700
Subject: [PATCH] enforce noCheck when useSysroot

---
 pkgs/build-support/rust/default.nix | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/pkgs/build-support/rust/default.nix b/pkgs/build-support/rust/default.nix
index e027853255c1..ae390816d0aa 100644
--- a/pkgs/build-support/rust/default.nix
+++ b/pkgs/build-support/rust/default.nix
@@ -105,6 +105,10 @@ let
 
 in
 
+# Tests don't currently work for `no_std`, and all custom sysroots are currently built without `std`.
+# See https://os.phil-opp.com/testing/ for more information.
+assert useSysroot -> !(args.doCheck or true);
+
 stdenv.mkDerivation ((removeAttrs args ["depsExtraArgs"]) // {
   inherit cargoDeps;