From d3a64dc989c22ada53ff380a530b1c95e205dc2a Mon Sep 17 00:00:00 2001
From: Niklas Korz <niklas@niklaskorz.de>
Date: Fri, 24 Jan 2025 16:58:26 +0100
Subject: [PATCH] zig: fix darwin SDK lookup

---
 pkgs/development/compilers/zig/generic.nix | 29 +++++++++++++++-------
 1 file changed, 20 insertions(+), 9 deletions(-)

diff --git a/pkgs/development/compilers/zig/generic.nix b/pkgs/development/compilers/zig/generic.nix
index 3da36c083bd3b..bdd10c9cfbda7 100644
--- a/pkgs/development/compilers/zig/generic.nix
+++ b/pkgs/development/compilers/zig/generic.nix
@@ -7,6 +7,7 @@
 , zlib
 , coreutils
 , callPackage
+, xcbuild
 , ...
 }:
 
@@ -50,15 +51,25 @@ stdenv.mkDerivation (finalAttrs: {
     export ZIG_GLOBAL_CACHE_DIR="$TMPDIR/zig-cache";
   '';
 
-  # Zig's build looks at /usr/bin/env to find dynamic linking info. This doesn't
-  # work in Nix's sandbox. Use env from our coreutils instead.
-  postPatch = if lib.versionAtLeast args.version "0.12" then ''
-    substituteInPlace lib/std/zig/system.zig \
-      --replace "/usr/bin/env" "${coreutils}/bin/env"
-  '' else ''
-    substituteInPlace lib/std/zig/system/NativeTargetInfo.zig \
-      --replace-fail "/usr/bin/env" "${coreutils}/bin/env"
-  '';
+  postPatch =
+    # Zig's build looks at /usr/bin/env to find dynamic linking info. This doesn't
+    # work in Nix's sandbox. Use env from our coreutils instead.
+    (if lib.versionAtLeast args.version "0.12" then ''
+      substituteInPlace lib/std/zig/system.zig \
+        --replace "/usr/bin/env" "${coreutils}/bin/env"
+    '' else ''
+      substituteInPlace lib/std/zig/system/NativeTargetInfo.zig \
+        --replace-fail "/usr/bin/env" "${coreutils}/bin/env"
+    '')
+    # Zig tries to access xcrun at the absolute system path to query the macOS SDK
+    # location, which does not work in the darwin sandbox.
+    # We can just provide "xcrun" instead as it is part of the darwin stdenv.
+    # Upstream issue: https://github.com/ziglang/zig/issues/22600
+    + lib.optionalString stdenv.hostPlatform.isDarwin ''
+      substituteInPlace lib/std/zig/system/darwin.zig \
+        --replace-fail /usr/bin/xcrun xcrun \
+        --replace-fail /usr/bin/xcode-select '${lib.getExe' xcbuild "xcode-select"}'
+    '';
 
   doInstallCheck = true;
   installCheckPhase = ''