klipper: fix cross

pkgs/servers/klipper/cross-ffi.patch

@@ -0,0 +1,14 @@
+diff --git a/klippy/chelper/__init__.py b/klippy/chelper/__init__.py
+index c26196e..b00bd97 100644
+--- a/chelper/__init__.py
++++ b/chelper/__init__.py
+@@ -318,11 +318,6 @@ def get_ffi():
+         FFI_main = cffi.FFI()
+         for d in defs_all:
+             FFI_main.cdef(d)
+-        FFI_lib = FFI_main.dlopen(destlib)
+-        # Setup error logging
+-        pyhelper_logging_callback = FFI_main.callback("void func(const char *)",
+-                                                      logging_callback)
+-        FFI_lib.set_python_logging_callback(pyhelper_logging_callback)
+     return FFI_main, FFI_lib

pkgs/servers/klipper/default.nix

@@ -3,6 +3,7 @@
   lib,
   fetchFromGitHub,
   python3,
+  python3Packages,
   extraPythonPackages ? ps: [ ],
   unstableGitUpdater,
   makeWrapper,
@@ -24,7 +25,7 @@ stdenv.mkDerivation rec {
 
   # NB: This is needed for the postBuild step
   nativeBuildInputs = [
-    (python3.withPackages (p: with p; [ cffi ]))
+    python3Packages.cffi
     makeWrapper
   ];
 
@@ -62,6 +63,11 @@ stdenv.mkDerivation rec {
       --replace 'GCC_CMD = "gcc"' 'GCC_CMD = "${stdenv.cc.targetPrefix}cc"'
   '';
 
+  patches = lib.optionals (stdenv.hostPlatform != stdenv.buildPlatform) [
+    # https://github.com/Klipper3d/klipper/pull/7254
+    ./cross-ffi.patch
+  ];
+
   pythonInterpreter =
     (python3.withPackages (
       p: with p; [