From 7269072659f41fdfc11ec5d3198925f911b4bb1d Mon Sep 17 00:00:00 2001
From: Philip Taron <philip.taron@gmail.com>
Date: Mon, 16 Feb 2026 08:53:43 -0800
Subject: [PATCH] buildEnv: fix passthru merging

Merge derivationArgs.passthru into the passthru chain so that passthru attributes passed via derivationArgs are not silently dropped.
---
 pkgs/build-support/buildenv/default.nix | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/pkgs/build-support/buildenv/default.nix b/pkgs/build-support/buildenv/default.nix
index 996034a01bb9..a3d8f38808d0 100644
--- a/pkgs/build-support/buildenv/default.nix
+++ b/pkgs/build-support/buildenv/default.nix
@@ -121,6 +121,10 @@ lib.makeOverridable (
           (lib.remove null)
         ];
       in
+      assert
+        args ? name
+        || (args ? pname && args ? version)
+        || throw "buildEnv: expects arguments 'pname' and 'version', or 'name'";
       compatArgs
       // derivationArgs
       // {
@@ -158,6 +162,7 @@ lib.makeOverridable (
           # The `paths` attribute is referenced and overridden from passthru
           inherit paths;
         }
+        // derivationArgs.passthru or { }
         // passthru;
       };