From 1147d724813cb9dbb8cd8728cf7ad195fa2155ca Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Na=C3=AFm=20Favier?= <n@monade.li>
Date: Thu, 20 Jan 2022 23:01:41 +0100
Subject: [PATCH] nixos: use `uniq` in the type of system.build

`unspecified` will happily concatenate strings together from two
unrelated modules, causing spurious errors (see #155925).
---
 nixos/modules/system/activation/top-level.nix | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/nixos/modules/system/activation/top-level.nix b/nixos/modules/system/activation/top-level.nix
index 1c588ff969184..8e53ec1ffab20 100644
--- a/nixos/modules/system/activation/top-level.nix
+++ b/nixos/modules/system/activation/top-level.nix
@@ -148,7 +148,7 @@ in
     system.build = mkOption {
       internal = true;
       default = {};
-      type = types.lazyAttrsOf types.unspecified;
+      type = with types; lazyAttrsOf (uniq unspecified);
       description = ''
         Attribute set of derivations used to setup the system.
       '';