TO REVERT: temporarily add a patch for rustc

0001-Allow-overwriting-the-sysroot-compile-flag-via-rustc.patch

@@ -0,0 +1,27 @@
+From 8d5e85607d3d52f920990334ae1cfa9798ad9259 Mon Sep 17 00:00:00 2001
+From: Antoni Boucher <[email protected]>
+Date: Thu, 8 Jun 2023 17:27:34 -0400
+Subject: [PATCH] Allow overwriting the sysroot compile flag via --rustc-args
+
+---
+ src/tools/compiletest/src/runtest.rs | 4 +++-
+ 1 file changed, 3 insertions(+), 1 deletion(-)
+
+diff --git a/src/tools/compiletest/src/runtest.rs b/src/tools/compiletest/src/runtest.rs
+index 6582b534488..d16a7d66154 100644
+--- a/src/tools/compiletest/src/runtest.rs
++++ b/src/tools/compiletest/src/runtest.rs
+@@ -1951,7 +1951,9 @@ fn make_compile_args(
+         rustc.arg("-Ztranslate-remapped-path-to-local-path=no");
+
+         // Optionally prevent default --sysroot if specified in test compile-flags.
+-        if !self.props.compile_flags.iter().any(|flag| flag.starts_with("--sysroot")) {
++        if !self.props.compile_flags.iter().any(|flag| flag.starts_with("--sysroot"))
++            && !self.config.host_rustcflags.iter().any(|flag| flag == "--sysroot")
++        {
+             // In stage 0, make sure we use `stage0-sysroot` instead of the bootstrap sysroot.
+             rustc.arg("--sysroot").arg(&self.config.sysroot_base);
+         }
+-- 
+2.41.0
+