From f2f8536be12f1d095382e7598060c1eb51eb5337 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micha=C5=82=20G=C3=B3rny?= <mgorny@gentoo.org>
Date: Wed, 9 May 2018 17:04:49 +0200
Subject: [PATCH] posix: Support GENTOO_SCONS_ENV_PASSTHROUGH=1

Support GENTOO_SCONS_ENV_PASSTHROUGH=1 variable to override the default
of wiping the environment and resetting PATH to default, and instead
pass all variables through.
---
 src/engine/SCons/Platform/posix.py | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/src/engine/SCons/Platform/posix.py b/src/engine/SCons/Platform/posix.py
index 8db08db1..af34650c 100644
--- a/src/engine/SCons/Platform/posix.py
+++ b/src/engine/SCons/Platform/posix.py
@@ -87,9 +87,17 @@ def generate(env):
     pspawn = piped_env_spawn
     # Note that this means that 'escape' is no longer used
 
-    if 'ENV' not in env:
-        env['ENV']        = {}
-    env['ENV']['PATH']    = '/usr/local/bin:/opt/bin:/bin:/usr/bin'
+    # Force pass-through of environment variables in Gentoo builds
+    if os.environ.get('GENTOO_SCONS_ENV_PASSTHROUGH', False):
+        new_env = os.environ.copy()
+        if 'ENV' in env:
+            new_env.update(env['ENV'])
+        env['ENV'] = new_env
+    else:
+        if 'ENV' not in env:
+            env['ENV']        = {}
+        env['ENV']['PATH']    = '/usr/local/bin:/opt/bin:/bin:/usr/bin'
+
     env['OBJPREFIX']      = ''
     env['OBJSUFFIX']      = '.o'
     env['SHOBJPREFIX']    = '$OBJPREFIX'
-- 
2.17.0