blob: 8233ee7bb7a5df6a6ec9278297382844999e43a8 [file] [log] [blame]
"""
This file assembles a toolchain for a Mac host (either M1 or Intel) using the Clang Compiler
and a locally-installed XCode.
It downloads the necessary executables and creates symlinks in the external subfolder of the Bazel
cache (the same place third party deps are downloaded with http_archive or similar functions in
WORKSPACE.bazel). These will be able to be used via our
custom c++ toolchain configuration (see //toolchain/mac_toolchain_config.bzl)
The destination folder for these files and symlinks are:
[outputRoot (aka Bazel cache)]/[outputUserRoot]/[outputBase]/external/clang_mac
(See https://bazel.build/docs/output_directories#layout-diagram)
"""
load(":clang_layering_check.bzl", "generate_system_module_map")
load(":utils.bzl", "gcs_mirror_url")
# From https://github.com/llvm/llvm-project/releases/tag/llvmorg-15.0.1
# When updating this, don't forget to use //bazel/gcs_mirror to upload a new version.
# go run bazel/gcs_mirror/gcs_mirror.go --url [clang_url] --sha256 [clang_sha256]
clang_prefix_arm64 = "clang+llvm-15.0.1-arm64-apple-darwin21.0"
clang_sha256_arm64 = "858f86d96b5e4880f69f7a583daddbf97ee94e7cffce0d53aa05cba6967f13b8"
clang_url_arm64 = "https://github.com/llvm/llvm-project/releases/download/llvmorg-15.0.1/clang+llvm-15.0.1-arm64-apple-darwin21.0.tar.xz"
clang_prefix_amd64 = "clang+llvm-15.0.1-x86_64-apple-darwin"
clang_sha256_amd64 = "0b2f1a811e68d011344103274733b7670c15bbe08b2a3a5140ccad8e19d9311e"
clang_url_amd64 = "https://github.com/llvm/llvm-project/releases/download/llvmorg-15.0.1/clang+llvm-15.0.1-x86_64-apple-darwin.tar.xz"
def _get_system_xcode_path(ctx):
# https://developer.apple.com/library/archive/technotes/tn2339/_index.html
res = ctx.execute(["xcode-select", "-p"])
if res.return_code != 0:
fail("Error Getting XCode path: " + res.stderr)
return res.stdout.rstrip()
def _delete_macos_sdk_symlinks(ctx):
ctx.delete("./symlinks/xcode/MacSDK/usr")
ctx.delete("./symlinks/xcode/MacSDK/Frameworks")
def _create_macos_sdk_symlinks(ctx):
system_xcode_path = _get_system_xcode_path(ctx)
# https://bazel.build/rules/lib/actions#symlink
ctx.symlink(
# from =
system_xcode_path + "/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr",
# to =
"./symlinks/xcode/MacSDK/usr",
)
ctx.symlink(
# from =
system_xcode_path + "/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/System/Library/Frameworks",
# to =
"./symlinks/xcode/MacSDK/Frameworks",
)
def _download_mac_toolchain_impl(ctx):
# https://bazel.build/rules/lib/repository_ctx#os
# https://bazel.build/rules/lib/repository_os
if ctx.os.arch == "aarch64":
clang_url = clang_url_arm64
clang_sha256 = clang_sha256_arm64
clang_prefix = clang_prefix_arm64
else:
clang_url = clang_url_amd64
clang_sha256 = clang_sha256_amd64
clang_prefix = clang_prefix_amd64
# Download the clang toolchain (the extraction can take a while)
# https://bazel.build/rules/lib/repository_ctx#download_and_extract
ctx.download_and_extract(
url = gcs_mirror_url(clang_url, clang_sha256),
output = "",
stripPrefix = clang_prefix,
sha256 = clang_sha256,
)
# Some std library headers use #include_next to include system specific headers, and
# some skia source files require Xcode headers when compiling, (see SkTypes.h and look
# for TargetedConditionals.h)) All of these are located in Xcode, stopping the Mac
# builds from being purely hermetic.
# For now, we can grab the user's Xcode path by calling xcode-select and create a symlink in
# our toolchain directory to refer to during compilation.
_delete_macos_sdk_symlinks(ctx)
_create_macos_sdk_symlinks(ctx)
# This list of files lines up with _make_default_flags() in mac_toolchain_config.bzl
# It is all locations that our toolchain could find a system header.
builtin_include_directories = [
"include/c++/v1",
"lib/clang/15.0.1/include",
"symlinks/xcode/Frameworks",
"symlinks/xcode/include",
]
generate_system_module_map(
ctx,
module_file = "toolchain_system_headers.modulemap",
folders = builtin_include_directories,
)
# Create a BUILD.bazel file that makes the files necessary for compiling,
# linking and creating archive files visible to Bazel.
# The smaller the globs are, the more performant the sandboxed builds will be.
# Additionally, globs that are too wide can pick up infinite symlink loops,
# and be difficult to quash: https://github.com/bazelbuild/bazel/issues/13950
# https://bazel.build/rules/lib/repository_ctx#file
ctx.file(
"BUILD.bazel",
content = """
# DO NOT EDIT THIS BAZEL FILE DIRECTLY
# Generated from ctx.file action in download_mac_toolchain.bzl
filegroup(
name = "generated_module_map",
srcs = ["toolchain_system_headers.modulemap"],
visibility = ["//visibility:public"],
)
filegroup(
name = "archive_files",
srcs = [
"bin/llvm-ar",
],
visibility = ["//visibility:public"],
)
filegroup(
name = "compile_files",
srcs = [
"bin/clang",
] + glob(
include = [
"include/c++/v1/**",
"lib/clang/15.0.1/include/**",
"symlinks/xcode/MacSDK/Frameworks/AppKit.Framework/**",
"symlinks/xcode/MacSDK/Frameworks/ApplicationServices.Framework/**",
"symlinks/xcode/MacSDK/Frameworks/Carbon.Framework/**",
"symlinks/xcode/MacSDK/Frameworks/CFNetwork.Framework/**",
"symlinks/xcode/MacSDK/Frameworks/CloudKit.Framework/**",
"symlinks/xcode/MacSDK/Frameworks/Cocoa.Framework/**",
"symlinks/xcode/MacSDK/Frameworks/ColorSync.Framework/**",
"symlinks/xcode/MacSDK/Frameworks/CoreData.Framework/**",
"symlinks/xcode/MacSDK/Frameworks/CoreFoundation.Framework/**",
"symlinks/xcode/MacSDK/Frameworks/CoreGraphics.Framework/**",
"symlinks/xcode/MacSDK/Frameworks/CoreImage.Framework/**",
"symlinks/xcode/MacSDK/Frameworks/CoreLocation.Framework/**",
"symlinks/xcode/MacSDK/Frameworks/CoreServices.Framework/**",
"symlinks/xcode/MacSDK/Frameworks/CoreText.Framework/**",
"symlinks/xcode/MacSDK/Frameworks/CoreVideo.Framework/**",
"symlinks/xcode/MacSDK/Frameworks/DiskArbitration.Framework/**",
"symlinks/xcode/MacSDK/Frameworks/Foundation.Framework/**",
"symlinks/xcode/MacSDK/Frameworks/ImageIO.Framework/**",
"symlinks/xcode/MacSDK/Frameworks/IOKit.Framework/**",
"symlinks/xcode/MacSDK/Frameworks/IOSurface.Framework/**",
"symlinks/xcode/MacSDK/Frameworks/Metal.Framework/**",
"symlinks/xcode/MacSDK/Frameworks/OpenGL.Framework/**",
"symlinks/xcode/MacSDK/Frameworks/QuartzCore.Framework/**",
"symlinks/xcode/MacSDK/Frameworks/Security.Framework/**",
"symlinks/xcode/MacSDK/usr/include/**",
],
allow_empty = False,
),
visibility = ["//visibility:public"],
)
filegroup(
name = "link_files",
srcs = [
"bin/clang",
"bin/ld.lld",
"bin/lld",
"lib/libc++.a",
"lib/libc++abi.a",
"lib/libunwind.a",
],
visibility = ["//visibility:public"],
)
""",
executable = False,
)
# https://bazel.build/rules/repository_rules
download_mac_toolchain = repository_rule(
implementation = _download_mac_toolchain_impl,
attrs = {},
doc = "Downloads clang to build Skia with." +
"Assumes you have xcode located on your device and have" +
"xcode-select in your $PATH.",
)