From 19bb0a96f41e639ea0b33dc92f9caa94d27e5a38 Mon Sep 17 00:00:00 2001
From: Alyssa Ross <hi@alyssa.is>
Date: Sat, 11 May 2024 10:38:30 +0200
Subject: [PATCH] rutabaga_gfx: build for the right architecture

Previously, cross compiling rutabaga_gfx looked like it worked, but it
produced binaries for the build machine.  This prevented
cross-compiling QEMU with rutabaga_gfx support enabled.

Fixes: 28257606653c ("rutabaga_gfx: init at 0.1.2")
---
 .../libraries/rutabaga_gfx/default.nix         | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/pkgs/development/libraries/rutabaga_gfx/default.nix b/pkgs/development/libraries/rutabaga_gfx/default.nix
index 687500272735..9b8f5bec42f3 100644
--- a/pkgs/development/libraries/rutabaga_gfx/default.nix
+++ b/pkgs/development/libraries/rutabaga_gfx/default.nix
@@ -54,14 +54,22 @@ stdenv.mkDerivation (finalAttrs: {
     hash = "sha256-wuF3Isrp+u5J8jPQoPsIOWYGNKLSNa2pLfvladAWkLs=";
   };
 
+  CARGO_BUILD_TARGET = stdenv.hostPlatform.rust.rustcTargetSpec;
+  "CARGO_TARGET_${stdenv.hostPlatform.rust.cargoEnvVarTarget}_LINKER" =
+    "${stdenv.cc.targetPrefix}cc";
+
+  postConfigure = ''
+    cd rutabaga_gfx/ffi
+    substituteInPlace Makefile --replace-fail pkg-config "$PKG_CONFIG"
+  '';
+
   # make install always rebuilds
   dontBuild = true;
 
-  makeFlags = [ "prefix=$(out)" ];
-
-  preInstall = ''
-    cd rutabaga_gfx/ffi
-  '';
+  makeFlags = [
+    "prefix=$(out)"
+    "OUT=target/${stdenv.hostPlatform.rust.cargoShortTarget}/release"
+  ];
 
   meta = with lib; {
     homepage = "https://crosvm.dev/book/appendix/rutabaga_gfx.html";