From db7888b13f94fd59194f0a2003968e7c11ac46d7 Mon Sep 17 00:00:00 2001
From: Keith Smiley <keithbsmiley@gmail.com>
Date: Thu, 21 Mar 2024 12:30:16 -0700
Subject: [PATCH] Detect supported features instead of using a Xcode version
 check

This is 1 step towards allowing us to support the Xcode Command Line
Tools without easily being able to tell what version of those are
installed.
---
 crosstool/BUILD.tpl               |  3 +++
 crosstool/cc_toolchain_config.bzl |  3 +--
 crosstool/osx_cc_configure.bzl    | 18 ++++++++++++++++++
 3 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/crosstool/BUILD.tpl b/crosstool/BUILD.tpl
index 8495ae5..1a1be01 100644
--- a/crosstool/BUILD.tpl
+++ b/crosstool/BUILD.tpl
@@ -79,6 +79,9 @@ cc_toolchain_suite(
     cc_toolchain_config(
         name = arch,
         cpu = arch,
+        features = [
+%{features}
+        ],
         cxx_builtin_include_directories = [
 %{cxx_builtin_include_directories}
         ],
diff --git a/crosstool/cc_toolchain_config.bzl b/crosstool/cc_toolchain_config.bzl
index 3353145..dc8868a 100644
--- a/crosstool/cc_toolchain_config.bzl
+++ b/crosstool/cc_toolchain_config.bzl
@@ -31,7 +31,6 @@ load(
     "with_feature_set",
 )
 load("@build_bazel_apple_support//lib:apple_support.bzl", "apple_support")
-load("@build_bazel_apple_support//lib:xcode_support.bzl", "xcode_support")
 
 # TODO: Remove when we drop bazel 6.x support
 _OBJC_ARCHIVE_ACTION_NAME = "objc-archive"
@@ -2509,7 +2508,7 @@ please file an issue at https://github.com/bazelbuild/apple_support/issues/new
     # these warnings.
     no_warn_duplicate_libraries_feature = feature(
         name = "no_warn_duplicate_libraries",
-        enabled = xcode_support.is_xcode_at_least_version(xcode_config, "15.0.0"),
+        enabled = "no_warn_duplicate_libraries" in ctx.features,
         flag_sets = [
             flag_set(
                 actions = _DYNAMIC_LINK_ACTIONS,
diff --git a/crosstool/osx_cc_configure.bzl b/crosstool/osx_cc_configure.bzl
index 94d4ca4..eb5b9b4 100644
--- a/crosstool/osx_cc_configure.bzl
+++ b/crosstool/osx_cc_configure.bzl
@@ -49,6 +49,19 @@ def _get_escaped_xcode_cxx_inc_directories(repository_ctx, xcode_toolchains):
 
     return include_dirs
 
+def _succeeds(repository_ctx, *args):
+    env = repository_ctx.os.environ
+    result = repository_ctx.execute([
+        "env",
+        "-i",
+        "DEVELOPER_DIR={}".format(env.get("DEVELOPER_DIR", default = "")),
+        "xcrun",
+        "--sdk",
+        "macosx",
+    ] + list(args))
+
+    return result.return_code == 0
+
 def _compile_cc_file(repository_ctx, src_name, out_name):
     env = repository_ctx.os.environ
     xcrun_result = repository_ctx.execute([
@@ -175,6 +188,10 @@ def configure_osx_toolchain(repository_ctx):
             gcov_path = repository_ctx.which(gcov_path)
         tool_paths["gcov"] = gcov_path
 
+    features = []
+    if _succeeds(repository_ctx, "ld", "-no_warn_duplicate_libraries", "-v"):
+        features.append("no_warn_duplicate_libraries")
+
     escaped_include_paths = _get_escaped_xcode_cxx_inc_directories(repository_ctx, xcode_toolchains)
     escaped_cxx_include_directories = []
     for path in escaped_include_paths:
@@ -186,6 +203,7 @@ def configure_osx_toolchain(repository_ctx):
         build_template,
         {
             "%{cxx_builtin_include_directories}": "\n".join(escaped_cxx_include_directories),
+            "%{features}": "\n".join(['"{}"'.format(x) for x in features]),
             "%{tool_paths_overrides}": ",\n            ".join(
                 ['"%s": "%s"' % (k, v) for k, v in tool_paths.items()],
             ),