From 670d6ac45824cc591e294a0a6e051f5dfbaa0c65 Mon Sep 17 00:00:00 2001
From: sternenseemann <0rpkxez4ksa01gb3typccl0i@systemli.org>
Date: Sat, 5 Jun 2021 12:38:24 +0200
Subject: [PATCH] haskell-generic-builder: fix buildTarget specification if
 isLibrary

If we don't pass buildTarget to ./Setup copy and buildTarget is not
empty it will try installing targets that don't exist and thus fail.
---
 pkgs/development/haskell-modules/generic-builder.nix | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pkgs/development/haskell-modules/generic-builder.nix b/pkgs/development/haskell-modules/generic-builder.nix
index a9c8f11223f7..b91da1669527 100644
--- a/pkgs/development/haskell-modules/generic-builder.nix
+++ b/pkgs/development/haskell-modules/generic-builder.nix
@@ -481,7 +481,7 @@ stdenv.mkDerivation ({
       # ^^ if the project is not a library, and we have a build target, then use "copy" to install
       # just the target specified; "install" will error here, since not all targets have been built.
     else ''
-      ${setupCommand} copy
+      ${setupCommand} copy ${buildTarget}
       local packageConfDir="$out/lib/${ghc.name}/package.conf.d"
       local packageConfFile="$packageConfDir/${pname}-${version}.conf"
       mkdir -p "$packageConfDir"