bazel: add darwin support

pkgs/build-support/trivial-builders.nix

@@ -72,6 +72,24 @@ rec {
       '';
     };
 
+  # Create a C binary
+  writeCBin = name: code:
+    runCommandCC name
+    {
+      inherit name code;
+      executable = true;
+      passAsFile = ["code"];
+      # Pointless to do this on a remote machine.
+      preferLocalBuild = true;
+      allowSubstitutes = false;
+    }
+    ''
+    n=$out/bin/$name
+    mkdir -p "$(dirname "$n")"
+    mv "$codePath" code.c
+    $CC -x c code.c -o "$n"
+    '';
+
   # Create a forest of symlinks to the files in `paths'.
   symlinkJoin =
     args_@{ name

pkgs/development/tools/build-managers/bazel/default.nix

@@ -1,7 +1,9 @@
-{ stdenv, lib, fetchurl, jdk, zip, unzip, bash, writeScriptBin, coreutils, makeWrapper, which, python
+{ stdenv, lib, fetchurl, jdk, zip, unzip, bash, writeCBin, coreutils, makeWrapper, which, python
 # Always assume all markers valid (don't redownload dependencies).
 # Also, don't clean up environment variables.
 , enableNixHacks ? false
+# Apple dependencies
+, libcxx, CoreFoundation, CoreServices, Foundation
 }:
 
 stdenv.mkDerivation rec {
@@ -13,7 +15,7 @@ stdenv.mkDerivation rec {
     description = "Build tool that builds code quickly and reliably";
     license = licenses.asl20;
     maintainers = [ maintainers.philandstuff ];
-    platforms = platforms.linux;
+    platforms = platforms.linux ++ platforms.darwin;
   };
 
   name = "bazel-${version}";
@@ -29,9 +31,30 @@ stdenv.mkDerivation rec {
 
   # Bazel expects several utils to be available in Bash even without PATH. Hence this hack.
 
-  customBash = writeScriptBin "bash" ''
-    #!${stdenv.shell}
-    PATH="$PATH:${lib.makeBinPath [ coreutils ]}" exec ${bash}/bin/bash "$@"
+  customBash = writeCBin "bash" ''
+    #include <stdio.h>
+    #include <stdlib.h>
+    #include <string.h>
+    #include <unistd.h>
+
+    extern char **environ;
+
+    int main(int argc, char *argv[]) {
+      printf("environ: %s\n", environ[0]);
+      char *path = getenv("PATH");
+      char *pathToAppend = "${lib.makeBinPath [ coreutils ]}";
+      char *newPath;
+      if (path != NULL) {
+        int length = strlen(path) + 1 + strlen(pathToAppend) + 1;
+        newPath = malloc(length * sizeof(char));
+        snprintf(newPath, length, "%s:%s", path, pathToAppend);
+      } else {
+        newPath = pathToAppend;
+      }
+      setenv("PATH", newPath, 1);
+      execve("${bash}/bin/bash", argv, environ);
+      return 0;
+    }
   '';
 
   postPatch = ''
@@ -54,7 +77,7 @@ stdenv.mkDerivation rec {
     makeWrapper
     which
     customBash
-  ];
+  ] ++ lib.optionals (stdenv.isDarwin) [ libcxx CoreFoundation CoreServices Foundation ];
 
   # If TMPDIR is in the unpack dir we run afoul of blaze's infinite symlink
   # detector (see com.google.devtools.build.lib.skyframe.FileFunction).

pkgs/top-level/all-packages.nix

@@ -7711,7 +7711,9 @@ with pkgs;
   bam = callPackage ../development/tools/build-managers/bam {};
 
   bazel_0_4 = callPackage ../development/tools/build-managers/bazel/0.4.nix { };
-  bazel = callPackage ../development/tools/build-managers/bazel { };
+  bazel = callPackage ../development/tools/build-managers/bazel {
+    inherit (darwin.apple_sdk.frameworks) CoreFoundation CoreServices Foundation;
+  };
 
   bazel-buildtools = callPackage ../development/tools/build-managers/bazel/buildtools { };
   buildifier = bazel-buildtools;