Ship llvm-libc as required by libcxx

.gitmodules

@@ -22,3 +22,6 @@
 [submodule "third_party/re2/src"]
 	path = third_party/re2/src
 	url = https://github.com/google/re2
+[submodule "third_party/llvm-libc/src"]
+	path = third_party/llvm-libc/src
+	url = https://chromium.googlesource.com/external/github.com/llvm/llvm-project/libc

buildtools/deps_revisions.gni

@@ -1,9 +1,9 @@
-# Copyright 2018 The Chromium Authors. All rights reserved.
+# Copyright 2018 The Chromium Authors
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 declare_args() {
-  # The libc++ svn revision that belongs to the git hash in DEPS. Used to cause
-  # full rebuilds on libc++ rolls.
-  libcxx_revision = "79a2e924d96e2fc1e4b937c42efd08898fa472d7"
+  # Used to cause full rebuilds on libc++ rolls. This should be kept in sync
+  # with the libcxx_revision var in //DEPS.
+  libcxx_revision = "d0ddad5b79581e19d8e1aec627bb2ad86e1554cd"
 }

scripts/create_dist.js

@@ -32,6 +32,7 @@ const gnzip = new JSZip()
 const files =
   searchFiles('build_overrides').concat(
   searchFiles('build')).concat(
+  searchFiles('buildtools/third_party')).concat(
   searchFiles('testing')).concat(
   searchFiles('tools/cfi')).concat(
   searchFiles('tools/clang/scripts')).concat(
@@ -46,15 +47,9 @@ const files =
   searchFiles('third_party/libc++abi/src/include')).concat(
   searchFiles('third_party/libunwind/src/src')).concat(
   searchFiles('third_party/libunwind/src/include')).concat(
+  searchFiles('third_party/llvm-libc')).concat(
   searchFiles('third_party/re2'))
 addFileToZip(gnzip, 'buildtools/deps_revisions.gni', '.')
-addFileToZip(gnzip, 'buildtools/third_party/eu-strip/bin/eu-strip', '.')
-addFileToZip(gnzip, 'buildtools/third_party/libc++/__assertion_handler', '.')
-addFileToZip(gnzip, 'buildtools/third_party/libc++/__config_site', '.')
-addFileToZip(gnzip, 'buildtools/third_party/libc++/BUILD.gn', '.')
-addFileToZip(gnzip, 'buildtools/third_party/libc++abi/cxa_demangle_stub.cc', '.')
-addFileToZip(gnzip, 'buildtools/third_party/libc++abi/BUILD.gn', '.')
-addFileToZip(gnzip, 'buildtools/third_party/libunwind/BUILD.gn', '.')
 for (let f of files) {
   addFileToZip(gnzip, f, '.')
 }

scripts/test.js

@@ -33,7 +33,9 @@ async function main() {
 }
 
 function runTests(error) {
-  for (const project of fs.readdirSync('examples')) {
+  const projects = process.argv.length > 2 ? process.argv.slice(2)
+                                           : fs.readdirSync('examples')
+  for (const project of projects) {
     runEachTest(project, path.resolve('examples', project))
   }
 }

third_party/llvm-libc/BUILD.gn

@@ -0,0 +1,16 @@
+# Copyright 2024 The Chromium Authors
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+config("config") {
+  visibility = [ ":*" ]
+  include_dirs = [ "src" ]
+  defines = [ "LIBC_NAMESPACE=__llvm_libc_cr" ]
+}
+
+group("llvm-libc-shared") {
+  # llvm-libc is only used as a dependency of libc++.
+  visibility = [ "//buildtools/third_party/libc++:libc++" ]
+
+  public_configs = [ ":config" ]
+}

third_party/llvm-libc/OWNERS

@@ -0,0 +1 @@
+file://third_party/libc++/OWNERS

third_party/llvm-libc/README.chromium

@@ -0,0 +1,12 @@
+Name: llvm-libc
+URL: https://libc.llvm.org/
+Version: N/A
+Revision: DEPS
+License: MIT, University of Illinois/NCSA Open Source License
+License File: src/LICENSE.TXT
+Security Critical: yes
+Shipped: yes
+
+Description:
+
+LLVM's C library. libc++ depends on a small subset of this for a few functions.

third_party/llvm-libc/README.md

@@ -0,0 +1 @@
+See README.chromium

tools/clang/scripts/update.py

@@ -254,7 +254,8 @@ def UpdatePackage(package_name, host_os, dir=LLVM_BUILD_DIR):
   assert package_file is not None
 
   # TODO(hans): Create a clang-win-runtime package and use separate DEPS hook.
-  target_os = []
+  # PATCH(build-gn): Provide a default target_os.
+  target_os = [host_os]
   if package_name == 'clang':
     try:
       GCLIENT_CONFIG = os.path.join(os.path.dirname(CHROMIUM_DIR), '.gclient')