From 78a7c9a9b9afeaec2341e3a09d7c634b285c917c Mon Sep 17 00:00:00 2001
From: Gaetan Lepage <gaetan@glepage.com>
Date: Mon, 2 Feb 2026 16:39:05 +0000
Subject: [PATCH 1/2] python3Packages.mmcv: cleanup

---
 .../python-modules/mmcv/default.nix           | 31 +++++++++----------
 1 file changed, 15 insertions(+), 16 deletions(-)

diff --git a/pkgs/development/python-modules/mmcv/default.nix b/pkgs/development/python-modules/mmcv/default.nix
index 8a0821999811..83fa155edc87 100644
--- a/pkgs/development/python-modules/mmcv/default.nix
+++ b/pkgs/development/python-modules/mmcv/default.nix
@@ -36,7 +36,7 @@ let
   inherit (torch) cudaCapabilities cudaPackages cudaSupport;
   inherit (cudaPackages) backendStdenv;
 in
-buildPythonPackage rec {
+buildPythonPackage (finalAttrs: {
   pname = "mmcv";
   version = "2.2.0";
   pyproject = true;
@@ -44,7 +44,7 @@ buildPythonPackage rec {
   src = fetchFromGitHub {
     owner = "open-mmlab";
     repo = "mmcv";
-    tag = "v${version}";
+    tag = "v${finalAttrs.version}";
     hash = "sha256-NNF9sLJWV1q6uBE73LUW4UWwYm4TBMTBJjJkFArBmsc=";
   };
 
@@ -57,7 +57,7 @@ buildPythonPackage rec {
     ''
       substituteInPlace setup.py \
         --replace-fail "cpu_use = 4" "cpu_use = $NIX_BUILD_CORES" \
-        --replace-fail "return locals()['__version__']" "return '${version}'"
+        --replace-fail "return locals()['__version__']" "return '${finalAttrs.version}'"
     '';
 
   nativeBuildInputs = [
@@ -93,17 +93,16 @@ buildPythonPackage rec {
     # torch
   ];
 
-  env.CUDA_HOME = lib.optionalString cudaSupport (lib.getDev cudaPackages.cuda_nvcc);
-
-  preConfigure = ''
-    export MMCV_WITH_OPS=1
-  ''
-  + lib.optionalString cudaSupport ''
-    export CC=${lib.getExe' backendStdenv.cc "cc"}
-    export CXX=${lib.getExe' backendStdenv.cc "c++"}
-    export TORCH_CUDA_ARCH_LIST="${lib.concatStringsSep ";" cudaCapabilities}"
-    export FORCE_CUDA=1
-  '';
+  env = {
+    CUDA_HOME = lib.optionalString cudaSupport (lib.getDev cudaPackages.cuda_nvcc);
+    MMCV_WITH_OPS = 1;
+  }
+  // lib.optionalAttrs cudaSupport {
+    CC = lib.getExe' backendStdenv.cc "cc";
+    CXX = lib.getExe' backendStdenv.cc "c++";
+    TORCH_CUDA_ARCH_LIST = lib.concatStringsSep ";" cudaCapabilities;
+    FORCE_CUDA = 1;
+  };
 
   pythonImportsCheck = [ "mmcv" ];
 
@@ -146,8 +145,8 @@ buildPythonPackage rec {
   meta = {
     description = "Foundational Library for Computer Vision Research";
     homepage = "https://github.com/open-mmlab/mmcv";
-    changelog = "https://github.com/open-mmlab/mmcv/releases/tag/v${version}";
+    changelog = "https://github.com/open-mmlab/mmcv/releases/tag/${finalAttrs.src.tag}";
     license = with lib.licenses; [ asl20 ];
     maintainers = with lib.maintainers; [ rxiao ];
   };
-}
+})

From 2603a3abe4bc7c4ff5001ab83dadacb6e9a194cb Mon Sep 17 00:00:00 2001
From: Gaetan Lepage <gaetan@glepage.com>
Date: Mon, 2 Feb 2026 16:57:51 +0000
Subject: [PATCH 2/2] python3Packages.mmcv: skip crashing test on x86_64-darwin

---
 pkgs/development/python-modules/mmcv/default.nix | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/pkgs/development/python-modules/mmcv/default.nix b/pkgs/development/python-modules/mmcv/default.nix
index 83fa155edc87..2f1984589ca5 100644
--- a/pkgs/development/python-modules/mmcv/default.nix
+++ b/pkgs/development/python-modules/mmcv/default.nix
@@ -140,6 +140,10 @@ buildPythonPackage (finalAttrs: {
     "test_ycbcr2rgb"
     "test_ycbcr2bgr"
     "test_tensor2imgs"
+  ]
+  ++ lib.optionals (stdenv.hostPlatform.isDarwin && stdenv.hostPlatform.isx86_64) [
+    # Fatal Python error: Segmentation fault
+    "test_transform"
   ];
 
   meta = {