From b563d910a099890033b62dfaf269ce85e44b0e4d Mon Sep 17 00:00:00 2001
From: Adam Joseph <adam@westernsemico.com>
Date: Mon, 14 Aug 2023 02:48:55 -0700
Subject: [PATCH 1/2] gnu-config: use the unpackPhase, so
 .overrideAttrs(_:{patches=...}) works

Prior to this PR, gnu-config did its unpacking in the `buildPhase`,
which mean that `.overrideAttrs(_:{ patches = ... })` couldn't be used to
test out patches to `gnu-config`.

This PR fixes that.
---
 .../libraries/gnu-config/default.nix          | 19 ++++++++++++++++---
 1 file changed, 16 insertions(+), 3 deletions(-)

diff --git a/pkgs/development/libraries/gnu-config/default.nix b/pkgs/development/libraries/gnu-config/default.nix
index 75a20bbbc355a51..4b115d47f98a0d5 100644
--- a/pkgs/development/libraries/gnu-config/default.nix
+++ b/pkgs/development/libraries/gnu-config/default.nix
@@ -23,9 +23,22 @@ in stdenv.mkDerivation {
   pname = "gnu-config";
   version = "2023-07-31";
 
-  buildCommand = ''
-    install -Dm755 ${configGuess} $out/config.guess
-    install -Dm755 ${configSub} $out/config.sub
+  unpackPhase = ''
+    runHook preUnpack
+    cp ${configGuess} ./config.guess
+    cp ${configSub} ./config.sub
+    chmod +w ./config.sub ./config.guess
+    runHook postUnpack
+  '';
+
+  dontConfigure = true;
+  dontBuild = true;
+
+  installPhase = ''
+    runHook preInstall
+    install -Dm755 ./config.guess $out/config.guess
+    install -Dm755 ./config.sub $out/config.sub
+    runHook postInstall
   '';
 
   meta = with lib; {

From 3ddf69b37d472e6cb548deb9ab0a3004543b4070 Mon Sep 17 00:00:00 2001
From: Adam Joseph <adam@westernsemico.com>
Date: Wed, 16 Aug 2023 05:25:37 -0700
Subject: [PATCH 2/2] gnu-config: set dontUpdateAutotoolsGnuConfigScripts =
 true

---
 pkgs/development/libraries/gnu-config/default.nix | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/pkgs/development/libraries/gnu-config/default.nix b/pkgs/development/libraries/gnu-config/default.nix
index 4b115d47f98a0d5..2b088eb459ad5e4 100644
--- a/pkgs/development/libraries/gnu-config/default.nix
+++ b/pkgs/development/libraries/gnu-config/default.nix
@@ -31,6 +31,13 @@ in stdenv.mkDerivation {
     runHook postUnpack
   '';
 
+  # If this isn't set, `pkgs.gnu-config.overrideAttrs( _: { patches
+  # = ...; })` will behave very counterintuitively: the (unpatched)
+  # gnu-config from the updateAutotoolsGnuConfigScriptsHook stdenv's
+  # defaultNativeBuildInputs will "update" the patched gnu-config by
+  # reverting the patch!
+  dontUpdateAutotoolsGnuConfigScripts = true;
+
   dontConfigure = true;
   dontBuild = true;