From 2e2ccb994b4c44535e2be1a14a741e6f14dd271e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?R=C3=A9mi=20Verschelde?= <rverschelde@gmail.com>
Date: Sat, 4 Apr 2020 12:12:10 +0200
Subject: [PATCH] SCons: Expand CXX in check for vanilla Clang

I had missed it in df7ecfc4a7f8403144be2aa49bb47f9ead25926b it seems.

Fixes #37575.
---
 methods.py | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/methods.py b/methods.py
index 89a229e4abb..805ae256c39 100644
--- a/methods.py
+++ b/methods.py
@@ -598,7 +598,11 @@ def detect_darwin_sdk_path(platform, env):
 def is_vanilla_clang(env):
     if not using_clang(env):
         return False
-    version = subprocess.check_output([env["CXX"], "--version"]).strip().decode("utf-8")
+    try:
+        version = subprocess.check_output([env.subst(env["CXX"]), "--version"]).strip().decode("utf-8")
+    except (subprocess.CalledProcessError, OSError):
+        print("Couldn't parse CXX environment variable to infer compiler version.")
+        return False
     return not version.startswith("Apple")