Remove pre Xcode 12 logic (#204)

We require Xcode 13+ (matching the App Store) at this point, so we don't
need to support versions that can't build for Apple Silicon

crosstool/osx_cc_configure.bzl

@@ -46,8 +46,7 @@ def _get_escaped_xcode_cxx_inc_directories(repository_ctx, xcode_toolchains):
 
     return include_dirs
 
-# TODO: Remove once Xcode 12 is the minimum supported version
-def _compile_cc_file_single_arch(repository_ctx, src_name, out_name):
+def _compile_cc_file(repository_ctx, src_name, out_name):
     env = repository_ctx.os.environ
     xcrun_result = repository_ctx.execute([
         "env",
@@ -60,12 +59,19 @@ def _compile_cc_file_single_arch(repository_ctx, src_name, out_name):
         "-mmacosx-version-min=10.13",
         "-std=c++11",
         "-lc++",
+        "-arch",
+        "arm64",
+        "-arch",
+        "x86_64",
+        "-Wl,-no_adhoc_codesign",
+        "-Wl,-no_uuid",
         "-O3",
         "-o",
         out_name,
         src_name,
     ])
-    if (xcrun_result.return_code != 0):
+
+    if xcrun_result.return_code != 0:
         error_msg = (
             "return code {code}, stderr: {err}, stdout: {out}"
         ).format(
@@ -74,59 +80,31 @@ def _compile_cc_file_single_arch(repository_ctx, src_name, out_name):
             out = xcrun_result.stdout,
         )
         fail(out_name + " failed to generate. Please file an issue at " +
-             "https://github.com/bazelbuild/bazel/issues with the following:\n" +
+             "https://github.com/bazelbuild/apple_support/issues with the following:\n" +
              error_msg)
 
-def _compile_cc_file(repository_ctx, src_name, out_name):
-    env = repository_ctx.os.environ
     xcrun_result = repository_ctx.execute([
         "env",
         "-i",
-        "DEVELOPER_DIR={}".format(env.get("DEVELOPER_DIR", default = "")),
-        "xcrun",
-        "--sdk",
-        "macosx",
-        "clang",
-        "-mmacosx-version-min=10.13",
-        "-std=c++11",
-        "-lc++",
-        "-arch",
-        "arm64",
-        "-arch",
-        "x86_64",
-        "-Wl,-no_adhoc_codesign",
-        "-Wl,-no_uuid",
-        "-O3",
-        "-o",
+        "codesign",
+        "--identifier",  # Required to be reproducible across archs
+        out_name,
+        "--force",
+        "--sign",
+        "-",
         out_name,
-        src_name,
     ])
-
-    if xcrun_result.return_code == 0:
-        xcrun_result = repository_ctx.execute([
-            "env",
-            "-i",
-            "codesign",
-            "--identifier",  # Required to be reproducible across archs
-            out_name,
-            "--force",
-            "--sign",
-            "-",
-            out_name,
-        ])
-        if xcrun_result.return_code != 0:
-            error_msg = (
-                "codesign return code {code}, stderr: {err}, stdout: {out}"
-            ).format(
-                code = xcrun_result.return_code,
-                err = xcrun_result.stderr,
-                out = xcrun_result.stdout,
-            )
-            fail(out_name + " failed to generate. Please file an issue at " +
-                 "https://github.com/bazelbuild/bazel/issues with the following:\n" +
-                 error_msg)
-    else:
-        _compile_cc_file_single_arch(repository_ctx, src_name, out_name)
+    if xcrun_result.return_code != 0:
+        error_msg = (
+            "codesign return code {code}, stderr: {err}, stdout: {out}"
+        ).format(
+            code = xcrun_result.return_code,
+            err = xcrun_result.stderr,
+            out = xcrun_result.stdout,
+        )
+        fail(out_name + " failed to generate. Please file an issue at " +
+             "https://github.com/bazelbuild/apple_support/issues with the following:\n" +
+             error_msg)
 
 def configure_osx_toolchain(repository_ctx):
     """Configure C++ toolchain on macOS.