From 6ccf14ba235944f96f67e252812d59ef1fb15e38 Mon Sep 17 00:00:00 2001
From: Terje Larsen <terlar@gmail.com>
Date: Wed, 30 Jul 2025 15:07:00 +0200
Subject: [PATCH] dockerTools.streamLayeredImage: fix enableFakechroot

This broke with #417132 where the previous behaviour of suppressing
errors of the export into $NIX_BUILD_TOP/env-vars when dumping env vars.

This error seems to stem from the non-existance of $NIX_BUILD_TOP. This
fix ensures the NIX_BUILD_TOP propagates into the proot environment.
---
 pkgs/build-support/docker/default.nix | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/pkgs/build-support/docker/default.nix b/pkgs/build-support/docker/default.nix
index 14b952424ca0..ecc7b410b54f 100644
--- a/pkgs/build-support/docker/default.nix
+++ b/pkgs/build-support/docker/default.nix
@@ -1049,6 +1049,7 @@ rec {
           "/proc/"
           "/sys/"
           "${builtins.storeDir}/"
+          "$NIX_BUILD_TOP"
           "$out/layer.tar"
         ]
       );
@@ -1085,6 +1086,7 @@ rec {
                     --exclude=./proc \
                     --exclude=./sys \
                     --exclude=.${builtins.storeDir} \
+                    --exclude=".$NIX_BUILD_TOP" \
                     --numeric-owner --mtime "@$SOURCE_DATE_EPOCH" \
                     --hard-dereference \
                     -cf $out/layer.tar .