Add new darwin CC toolchain for tests (#1017)

examples/.bazelrc

@@ -1,8 +1,13 @@
-
 # Required for Windows
 build --enable_runfiles
 
 # These are required otherwise paths are too long
 startup --windows_enable_symlinks
 build --action_env=MSYS=winsymlinks:nativestrict
 test --action_env=MSYS=winsymlinks:nativestrict
+
+# Enable CC toolchain that supports iOS from https://github.com/bazelbuild/apple_support
+build --enable_platform_specific_config
+build:macos --apple_crosstool_top=@local_config_apple_cc//:toolchain
+build:macos --crosstool_top=@local_config_apple_cc//:toolchain
+build:macos --host_crosstool_top=@local_config_apple_cc//:toolchain

examples/WORKSPACE.bazel

@@ -57,6 +57,13 @@ rbe_preconfig(
     toolchain = "ubuntu1804-bazel-java11",
 )
 
+http_archive(
+    name = "build_bazel_apple_support",
+    patches = ["//deps:apple_support.patch"],
+    sha256 = "77a121a0f5d4cd88824429464ad2bfb54bdc8a3bccdb4d31a6c846003a3f5e44",
+    url = "https://github.com/bazelbuild/apple_support/releases/download/1.4.1/apple_support.1.4.1.tar.gz",
+)
+
 http_archive(
     name = "build_bazel_rules_apple",
     sha256 = "12865e5944f09d16364aa78050366aca9dc35a32a018fa35f5950238b08bf744",

examples/deps/apple_support.patch

@@ -0,0 +1,8 @@
+--- crosstool/setup.bzl
++++ crosstool/setup.bzl
+@@ -66,5 +66,3 @@ def apple_cc_configure():
+ def _apple_cc_configure_extension_impl(_):
+     _apple_cc_autoconf_toolchains(name = "local_config_apple_cc_toolchains")
+     _apple_cc_autoconf(name = "local_config_apple_cc")
+-
+-apple_cc_configure_extension = module_extension(implementation = _apple_cc_configure_extension_impl)