From 5940d931f4b48d67372071f57915fe2137af3053 Mon Sep 17 00:00:00 2001
From: Henrik Lissner <henrik@lissner.net>
Date: Tue, 1 Sep 2020 15:12:10 -0400
Subject: [PATCH] Fix "read only variable" errors on doom {sync,upgrade}

Relevant to #3844
---
 bin/doom | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/bin/doom b/bin/doom
index 440872814..d0dd4e0ee 100755
--- a/bin/doom
+++ b/bin/doom
@@ -112,7 +112,10 @@
                         "\n  ")))
                 "\n}\n"
                 (save-match-data
-                  (cl-loop for env in process-environment
+                  (cl-loop for env
+                           in (cl-set-difference process-environment
+                                                 doom--initial-process-environment
+                                                 :test #'equal)
                            if (string-match "^\\([a-zA-Z0-9_]+\\)=\\(.+\\)$" env)
                            concat (format "%s=%s \\\n"
                                           (match-string 1 env)