python3Packages.jaxlib-build: share fetch derivation between differen…

…t build derivations

pkgs/development/python-modules/jaxlib/default.nix

@@ -86,7 +86,50 @@ let
     ];
   };
 
-  bazel-build = buildBazelPackage {
+  # Copy-paste from TF derivation.
+  # Most of these are not really used in jaxlib compilation but it's simpler to keep it
+  # 'as is' so that it's more compatible with TF derivation.
+  tf_system_libs = [
+    "absl_py"
+    "astor_archive"
+    "astunparse_archive"
+    "boringssl"
+    # Not packaged in nixpkgs
+    # "com_github_googleapis_googleapis"
+    # "com_github_googlecloudplatform_google_cloud_cpp"
+    "com_github_grpc_grpc"
+    "com_google_protobuf"
+    # Fails with the error: external/org_tensorflow/tensorflow/core/profiler/utils/tf_op_utils.cc:46:49: error: no matching function for call to 're2::RE2::FullMatch(absl::lts_2020_02_25::string_view&, re2::RE2&)'
+    # "com_googlesource_code_re2"
+    "curl"
+    "cython"
+    "dill_archive"
+    "double_conversion"
+    "flatbuffers"
+    "functools32_archive"
+    "gast_archive"
+    "gif"
+    "hwloc"
+    "icu"
+    "jsoncpp_git"
+    "libjpeg_turbo"
+    "lmdb"
+    "nasm"
+    "opt_einsum_archive"
+    "org_sqlite"
+    "pasta"
+    "png"
+    "pybind11"
+    "six_archive"
+    "snappy"
+    "tblib_archive"
+    "termcolor_archive"
+    "typing_extensions_archive"
+    "wrapt"
+    "zlib"
+  ];
+
+  bazel-build = buildBazelPackage rec {
     name = "bazel-build-${pname}-${version}";
 
     bazel = bazel_5;
@@ -169,83 +212,55 @@ let
       CFG
     '';
 
-    # Copy-paste from TF derivation.
-    # Most of these are not really used in jaxlib compilation but it's simpler to keep it
-    # 'as is' so that it's more compatible with TF derivation.
-    TF_SYSTEM_LIBS = lib.concatStringsSep "," ([
-      "absl_py"
-      "astor_archive"
-      "astunparse_archive"
-      "boringssl"
-      # Not packaged in nixpkgs
-      # "com_github_googleapis_googleapis"
-      # "com_github_googlecloudplatform_google_cloud_cpp"
-      "com_github_grpc_grpc"
-      "com_google_protobuf"
-      # Fails with the error: external/org_tensorflow/tensorflow/core/profiler/utils/tf_op_utils.cc:46:49: error: no matching function for call to 're2::RE2::FullMatch(absl::lts_2020_02_25::string_view&, re2::RE2&)'
-      # "com_googlesource_code_re2"
-      "curl"
-      "cython"
-      "dill_archive"
-      "double_conversion"
-      "flatbuffers"
-      "functools32_archive"
-      "gast_archive"
-      "gif"
-      "hwloc"
-      "icu"
-      "jsoncpp_git"
-      "libjpeg_turbo"
-      "lmdb"
-      "nasm"
-      "opt_einsum_archive"
-      "org_sqlite"
-      "pasta"
-      "png"
-      "pybind11"
-      "six_archive"
-      "snappy"
-      "tblib_archive"
-      "termcolor_archive"
-      "typing_extensions_archive"
-      "wrapt"
-      "zlib"
-    ] ++ lib.optionals (!stdenv.isDarwin) [
-      "nsync" # fails to build on darwin
-    ]);
-
     # Make sure Bazel knows about our configuration flags during fetching so that the
     # relevant dependencies can be downloaded.
     bazelFlags = [
       "-c opt"
-    ] ++ lib.optionals (stdenv.targetPlatform.isx86_64 && stdenv.targetPlatform.isUnix) [
-      "--config=avx_posix"
-    ] ++ lib.optionals cudaSupport [
-      "--config=cuda"
-    ] ++ lib.optionals mklSupport [
-      "--config=mkl_open_source_only"
     ] ++ lib.optionals stdenv.cc.isClang [
       # bazel depends on the compiler frontend automatically selecting these flags based on file
       # extension but our clang doesn't.
       # https://github.com/NixOS/nixpkgs/issues/150655
       "--cxxopt=-x" "--cxxopt=c++" "--host_cxxopt=-x" "--host_cxxopt=c++"
     ];
 
+    # We intentionally overfetch so we can share the fetch derivation across all the different configurations
     fetchAttrs = {
+      TF_SYSTEM_LIBS = lib.concatStringsSep "," tf_system_libs;
+      # we have to force @mkl_dnn_v1 since it's not needed on darwin
+      bazelTargets = bazelTargets ++ [ "@mkl_dnn_v1//:mkl_dnn" ];
+      bazelFlags = bazelFlags ++ [
+        "--config=avx_posix"
+      ] ++ lib.optionals cudaSupport [
+        # ideally we'd add this unconditionally too, but it doesn't work on darwin
+        # we make this conditional on `cudaSupport` instead of the system, so that the hash for both
+        # the cuda and the non-cuda deps can be computed on linux, since a lot of contributors don't
+        # have access to darwin machines
+        "--config=cuda"
+      ] ++ [
+        "--config=mkl_open_source_only"
+      ];
+
       sha256 =
         if cudaSupport then
-          "sha256-n8wo+hD9ZYO1SsJKgyJzUmjRlsz45WT6tt5ZLleGvGY="
-        else {
-          x86_64-linux = "sha256-A0A18kxgGNGHNQ67ZPUzh3Yq2LEcRV7CqR9EfP80NQk=";
-          aarch64-linux = "sha256-mU2jzuDu89jVmaG/M5bA3jSd7n7lDi+h8sdhs1z8p1A=";
-          x86_64-darwin = "sha256-9nNTpetvjyipD/l8vKlregl1j/OnZKAcOCoZQeRBvts=";
-          aarch64-darwin = "sha256-FqYwI1YC5eqSv+DYj09DC5IaBfFDUCO97y+TFhGiWAA=";
-        }.${stdenv.system} or (throw "unsupported system ${stdenv.system}");
+          "sha256-4yu4y4SwSQoeaOz9yojhvCRGSC6jp61ycVDIKyIK/l8="
+        else
+          "sha256-CyRfPfJc600M7VzR3/SQX/EAyeaXRJwDQWot5h2XnFU=";
     };
 
     buildAttrs = {
       outputs = [ "out" ];
 
+      TF_SYSTEM_LIBS = lib.concatStringsSep "," (tf_system_libs ++ lib.optionals (!stdenv.isDarwin) [
+        "nsync" # fails to build on darwin
+      ]);
+
+      bazelFlags = bazelFlags ++ lib.optionals (stdenv.targetPlatform.isx86_64 && stdenv.targetPlatform.isUnix) [
+        "--config=avx_posix"
+      ] ++ lib.optionals cudaSupport [
+        "--config=cuda"
+      ] ++ lib.optionals mklSupport [
+        "--config=mkl_open_source_only"
+      ];
       # Note: we cannot do most of this patching at `patch` phase as the deps are not available yet.
       # 1) Fix pybind11 include paths.
       # 2) Link protobuf from nixpkgs (through TF_SYSTEM_LIBS when using gcc) to prevent crashes on