test: rebuild nan tests with libc++ and libc++abi (#29281)

* test: re-enable nan test: typedarrays-test.js

Fixes #28414.

I've confirmed this fix wfm on Linux. Pushing into a PR to get CI to run
it out on Win and Mac platforms too.

* chore: clarify comment

* test: fix NAN test string alignment

* test: (wip) add ldflags, archive file for libc++

* test: (wip) add libc++ to CircleCI

* test: (wip) add llvm flags

* test: (wip) change ldflag syntax

* test: (wip) build libc++abi as static

* fix: correct ldflags

* test: add ld env

* fix: do not commit this

* test: add lld from src to circleci

* test: add lld link to ld

* chore: preserve third_party

* seems legit

* sam swears this works kinda sort of sometimes'
:

* build: add gn visibility patch

* chore: update patches

* build: check for flatten_relative_to = false

* build: upload zip files, add to release.js validation

* debug: what the hell gn

* build: add libcxx gni to lint ignore

Linting the file adjusted the licenses array, which only contains
one value, and causes the gn check to fail later

* build: also use nan-spec-runner flags on Windows

* build: add linked flags for win32 only

* build: build libc++ as source on win

* build: clean up patch, add -fPIC for IA32

* build: delete libcxx .a files from root

* build: rename libc++.zip, clean up upload per platform

* build: fix gni lint

* ci: add libcxx gen to circleci config

* build: correct libcxx-object syntax

Co-authored-by: Samuel Attard <sam@electronjs.org>

Co-authored-by: Charles Kerr <charles@charleskerr.com>
Co-authored-by: clavin <clavin@electronjs.org>
Co-authored-by: Samuel Attard <sattard@slack-corp.com>
Co-authored-by: PatchUp <73610968+patchup[bot]@users.noreply.github.com>
Co-authored-by: Samuel Attard <sam@electronjs.org>

.circleci/config.yml

@@ -499,6 +499,7 @@ step-gn-check: &step-gn-check
       gn check out/Default //electron/shell/common/api:mojo
       # Check the hunspell filenames
       node electron/script/gen-hunspell-filenames.js --check
+      node electron/script/gen-libc++-filenames.js --check
 
 step-electron-build: &step-electron-build
   run:
@@ -662,6 +663,11 @@ step-persist-data-for-tests: &step-persist-data-for-tests
       - src/third_party/electron_node
       - src/third_party/nan
       - src/cross-arch-snapshots
+      - src/third_party/llvm-build
+      - src/build/linux
+      - src/buildtools/third_party/libc++
+      - src/buildtools/third_party/libc++abi
+      - src/out/Default/obj/buildtools/third_party
 
 step-electron-dist-unzip: &step-electron-dist-unzip
   run:
@@ -797,6 +803,17 @@ step-hunspell-build: &step-hunspell-build
         ninja -C out/Default electron:hunspell_dictionaries_zip -j $NUMBER_OF_NINJA_PROCESSES
       fi
 
+step-maybe-generate-libcxx: &step-maybe-generate-libcxx
+  run:
+    name: maybe generate libcxx
+    command: |
+      cd src
+      if [ "`uname`" == "Linux" ]; then
+        ninja -C out/Default electron:libcxx_headers_zip -j $NUMBER_OF_NINJA_PROCESSES
+        ninja -C out/Default electron:libcxxabi_headers_zip -j $NUMBER_OF_NINJA_PROCESSES
+        ninja -C out/Default electron:libcxx_objects_zip -j $NUMBER_OF_NINJA_PROCESSES
+      fi
+
 step-maybe-generate-breakpad-symbols: &step-maybe-generate-breakpad-symbols
   run:
     name: Generate breakpad symbols
@@ -1620,6 +1637,9 @@ commands:
       # hunspell
       - *step-hunspell-build
 
+      # libcxx
+      - *step-maybe-generate-libcxx
+
       # typescript defs
       - *step-maybe-generate-typescript-defs
 

BUILD.gn

@@ -25,6 +25,8 @@ import("electron_paks.gni")
 import("filenames.auto.gni")
 import("filenames.gni")
 import("filenames.hunspell.gni")
+import("filenames.libcxx.gni")
+import("filenames.libcxxabi.gni")
 
 if (is_mac) {
   import("//build/config/mac/rules.gni")
@@ -1293,13 +1295,18 @@ template("dist_zip") {
                              "testonly",
                            ])
     flatten = false
+    flatten_relative_to = false
     if (defined(invoker.flatten)) {
       flatten = invoker.flatten
+      if (defined(invoker.flatten_relative_to)) {
+        flatten_relative_to = invoker.flatten_relative_to
+      }
     }
     args = rebase_path(outputs + [ _runtime_deps_file ], root_build_dir) + [
              target_cpu,
              target_os,
              "$flatten",
+             "$flatten_relative_to",
            ]
   }
 }
@@ -1390,6 +1397,43 @@ dist_zip("hunspell_dictionaries_zip") {
   outputs = [ "$root_build_dir/hunspell_dictionaries.zip" ]
 }
 
+copy("libcxx_headers") {
+  sources = libcxx_headers + libcxx_licenses
+  outputs = [ "$target_gen_dir/electron_libcxx_include/{{source_root_relative_dir}}/{{source_file_part}}" ]
+}
+
+dist_zip("libcxx_headers_zip") {
+  data_deps = [ ":libcxx_headers" ]
+  flatten = true
+  flatten_relative_to = rebase_path(
+          "$target_gen_dir/electron_libcxx_include/buildtools/third_party/libc++/trunk",
+          "$root_out_dir")
+
+  outputs = [ "$root_build_dir/libcxx_headers.zip" ]
+}
+
+copy("libcxxabi_headers") {
+  sources = libcxxabi_headers + libcxxabi_licenses
+  outputs = [ "$target_gen_dir/electron_libcxxabi_include/{{source_root_relative_dir}}/{{source_file_part}}" ]
+}
+
+dist_zip("libcxxabi_headers_zip") {
+  data_deps = [ ":libcxxabi_headers" ]
+  flatten = true
+  flatten_relative_to = rebase_path(
+          "$target_gen_dir/electron_libcxxabi_include/buildtools/third_party/libc++abi/trunk",
+          "$root_out_dir")
+
+  outputs = [ "$root_build_dir/libcxxabi_headers.zip" ]
+}
+
+action("libcxx_zip") {
+  deps = [ "//buildtools/third_party/libc++" ]
+  script = "build/zip_libcxx.py"
+  outputs = [ "$root_build_dir/libcxx_objects.zip" ]
+  args = rebase_path(outputs)
+}
+
 group("electron") {
   public_deps = [ ":electron_app" ]
 }

build/zip.py

@@ -72,7 +72,7 @@ def execute(argv):
     raise e
 
 def main(argv):
-  dist_zip, runtime_deps, target_cpu, _, flatten_val = argv
+  dist_zip, runtime_deps, target_cpu, _, flatten_val, flatten_relative_to = argv
   should_flatten = flatten_val == "true"
   dist_files = set()
   with open(runtime_deps) as f:
@@ -99,11 +99,18 @@ def main(argv):
             if basename == 'chrome_sandbox'
             else dep
           )
+          name_to_write = arcname
+          if should_flatten:
+            if flatten_relative_to:
+              if name_to_write.startswith(flatten_relative_to):
+                name_to_write = name_to_write[len(flatten_relative_to):]
+              else:
+                name_to_write = os.path.basename(arcname)
+            else:
+              name_to_write = os.path.basename(arcname)
           z.write(
             dep,
-            os.path.basename(arcname)
-            if should_flatten
-            else arcname,
+            name_to_write,
           )
 
 if __name__ == '__main__':

build/zip_libcxx.py

@@ -0,0 +1,44 @@
+#!/usr/bin/env python
+from __future__ import print_function
+import os
+import subprocess
+import sys
+import zipfile
+
+def execute(argv):
+  try:
+    output = subprocess.check_output(argv, stderr=subprocess.STDOUT)
+    return output
+  except subprocess.CalledProcessError as e:
+    print(e.output)
+    raise e
+
+def get_object_files(base_path, archive_name):
+  archive_file = os.path.join(base_path, archive_name)
+  output = execute(['nm', '-g', archive_file]).decode('ascii')
+  object_files = set()
+  lines = output.split("\n")
+  for line in lines:
+    if line.startswith(base_path):
+      object_file = line.split(":")[0]
+      object_files.add(object_file)
+  return list(object_files) + [archive_file]
+
+def main(argv):
+  dist_zip, = argv
+  out_dir = os.path.dirname(dist_zip)
+  base_path_libcxx = os.path.join(out_dir, 'obj/buildtools/third_party/libc++')
+  base_path_libcxxabi = os.path.join(out_dir, 'obj/buildtools/third_party/libc++abi')
+  object_files_libcxx = get_object_files(base_path_libcxx, 'libc++.a')
+  object_files_libcxxabi = get_object_files(base_path_libcxxabi, 'libc++abi.a')
+  with zipfile.ZipFile(
+      dist_zip, 'w', zipfile.ZIP_DEFLATED, allowZip64=True
+    ) as z:
+      object_files_libcxx.sort()
+      for object_file in object_files_libcxx:
+        z.write(object_file, os.path.relpath(object_file, base_path_libcxx))
+      for object_file in object_files_libcxxabi:
+        z.write(object_file, os.path.relpath(object_file, base_path_libcxxabi))
+
+if __name__ == '__main__':
+  sys.exit(main(sys.argv[1:]))

filenames.libcxx.gni

@@ -0,0 +1,194 @@
+libcxx_headers = [
+  "//buildtools/third_party/libc++/trunk/include/CMakeLists.txt",
+  "//buildtools/third_party/libc++/trunk/include/__availability",
+  "//buildtools/third_party/libc++/trunk/include/__bit_reference",
+  "//buildtools/third_party/libc++/trunk/include/__bits",
+  "//buildtools/third_party/libc++/trunk/include/__bsd_locale_defaults.h",
+  "//buildtools/third_party/libc++/trunk/include/__bsd_locale_fallbacks.h",
+  "//buildtools/third_party/libc++/trunk/include/__config",
+  "//buildtools/third_party/libc++/trunk/include/__config_site.in",
+  "//buildtools/third_party/libc++/trunk/include/__debug",
+  "//buildtools/third_party/libc++/trunk/include/__errc",
+  "//buildtools/third_party/libc++/trunk/include/__functional_03",
+  "//buildtools/third_party/libc++/trunk/include/__functional_base",
+  "//buildtools/third_party/libc++/trunk/include/__functional_base_03",
+  "//buildtools/third_party/libc++/trunk/include/__hash_table",
+  "//buildtools/third_party/libc++/trunk/include/__libcpp_version",
+  "//buildtools/third_party/libc++/trunk/include/__locale",
+  "//buildtools/third_party/libc++/trunk/include/__memory/allocator_traits.h",
+  "//buildtools/third_party/libc++/trunk/include/__memory/base.h",
+  "//buildtools/third_party/libc++/trunk/include/__memory/pointer_traits.h",
+  "//buildtools/third_party/libc++/trunk/include/__memory/utilities.h",
+  "//buildtools/third_party/libc++/trunk/include/__mutex_base",
+  "//buildtools/third_party/libc++/trunk/include/__node_handle",
+  "//buildtools/third_party/libc++/trunk/include/__nullptr",
+  "//buildtools/third_party/libc++/trunk/include/__split_buffer",
+  "//buildtools/third_party/libc++/trunk/include/__sso_allocator",
+  "//buildtools/third_party/libc++/trunk/include/__std_stream",
+  "//buildtools/third_party/libc++/trunk/include/__string",
+  "//buildtools/third_party/libc++/trunk/include/__support/android/locale_bionic.h",
+  "//buildtools/third_party/libc++/trunk/include/__support/fuchsia/xlocale.h",
+  "//buildtools/third_party/libc++/trunk/include/__support/ibm/limits.h",
+  "//buildtools/third_party/libc++/trunk/include/__support/ibm/locale_mgmt_aix.h",
+  "//buildtools/third_party/libc++/trunk/include/__support/ibm/nanosleep.h",
+  "//buildtools/third_party/libc++/trunk/include/__support/ibm/support.h",
+  "//buildtools/third_party/libc++/trunk/include/__support/ibm/xlocale.h",
+  "//buildtools/third_party/libc++/trunk/include/__support/musl/xlocale.h",
+  "//buildtools/third_party/libc++/trunk/include/__support/newlib/xlocale.h",
+  "//buildtools/third_party/libc++/trunk/include/__support/nuttx/xlocale.h",
+  "//buildtools/third_party/libc++/trunk/include/__support/openbsd/xlocale.h",
+  "//buildtools/third_party/libc++/trunk/include/__support/solaris/floatingpoint.h",
+  "//buildtools/third_party/libc++/trunk/include/__support/solaris/wchar.h",
+  "//buildtools/third_party/libc++/trunk/include/__support/solaris/xlocale.h",
+  "//buildtools/third_party/libc++/trunk/include/__support/win32/limits_msvc_win32.h",
+  "//buildtools/third_party/libc++/trunk/include/__support/win32/locale_win32.h",
+  "//buildtools/third_party/libc++/trunk/include/__support/xlocale/__nop_locale_mgmt.h",
+  "//buildtools/third_party/libc++/trunk/include/__support/xlocale/__posix_l_fallback.h",
+  "//buildtools/third_party/libc++/trunk/include/__support/xlocale/__strtonum_fallback.h",
+  "//buildtools/third_party/libc++/trunk/include/__threading_support",
+  "//buildtools/third_party/libc++/trunk/include/__tree",
+  "//buildtools/third_party/libc++/trunk/include/__tuple",
+  "//buildtools/third_party/libc++/trunk/include/__undef_macros",
+  "//buildtools/third_party/libc++/trunk/include/algorithm",
+  "//buildtools/third_party/libc++/trunk/include/any",
+  "//buildtools/third_party/libc++/trunk/include/array",
+  "//buildtools/third_party/libc++/trunk/include/atomic",
+  "//buildtools/third_party/libc++/trunk/include/barrier",
+  "//buildtools/third_party/libc++/trunk/include/bit",
+  "//buildtools/third_party/libc++/trunk/include/bitset",
+  "//buildtools/third_party/libc++/trunk/include/cassert",
+  "//buildtools/third_party/libc++/trunk/include/ccomplex",
+  "//buildtools/third_party/libc++/trunk/include/cctype",
+  "//buildtools/third_party/libc++/trunk/include/cerrno",
+  "//buildtools/third_party/libc++/trunk/include/cfenv",
+  "//buildtools/third_party/libc++/trunk/include/cfloat",
+  "//buildtools/third_party/libc++/trunk/include/charconv",
+  "//buildtools/third_party/libc++/trunk/include/chrono",
+  "//buildtools/third_party/libc++/trunk/include/cinttypes",
+  "//buildtools/third_party/libc++/trunk/include/ciso646",
+  "//buildtools/third_party/libc++/trunk/include/climits",
+  "//buildtools/third_party/libc++/trunk/include/clocale",
+  "//buildtools/third_party/libc++/trunk/include/cmath",
+  "//buildtools/third_party/libc++/trunk/include/codecvt",
+  "//buildtools/third_party/libc++/trunk/include/compare",
+  "//buildtools/third_party/libc++/trunk/include/complex",
+  "//buildtools/third_party/libc++/trunk/include/complex.h",
+  "//buildtools/third_party/libc++/trunk/include/concepts",
+  "//buildtools/third_party/libc++/trunk/include/condition_variable",
+  "//buildtools/third_party/libc++/trunk/include/csetjmp",
+  "//buildtools/third_party/libc++/trunk/include/csignal",
+  "//buildtools/third_party/libc++/trunk/include/cstdarg",
+  "//buildtools/third_party/libc++/trunk/include/cstdbool",
+  "//buildtools/third_party/libc++/trunk/include/cstddef",
+  "//buildtools/third_party/libc++/trunk/include/cstdint",
+  "//buildtools/third_party/libc++/trunk/include/cstdio",
+  "//buildtools/third_party/libc++/trunk/include/cstdlib",
+  "//buildtools/third_party/libc++/trunk/include/cstring",
+  "//buildtools/third_party/libc++/trunk/include/ctgmath",
+  "//buildtools/third_party/libc++/trunk/include/ctime",
+  "//buildtools/third_party/libc++/trunk/include/ctype.h",
+  "//buildtools/third_party/libc++/trunk/include/cwchar",
+  "//buildtools/third_party/libc++/trunk/include/cwctype",
+  "//buildtools/third_party/libc++/trunk/include/deque",
+  "//buildtools/third_party/libc++/trunk/include/errno.h",
+  "//buildtools/third_party/libc++/trunk/include/exception",
+  "//buildtools/third_party/libc++/trunk/include/execution",
+  "//buildtools/third_party/libc++/trunk/include/experimental/__config",
+  "//buildtools/third_party/libc++/trunk/include/experimental/__memory",
+  "//buildtools/third_party/libc++/trunk/include/experimental/algorithm",
+  "//buildtools/third_party/libc++/trunk/include/experimental/coroutine",
+  "//buildtools/third_party/libc++/trunk/include/experimental/deque",
+  "//buildtools/third_party/libc++/trunk/include/experimental/filesystem",
+  "//buildtools/third_party/libc++/trunk/include/experimental/forward_list",
+  "//buildtools/third_party/libc++/trunk/include/experimental/functional",
+  "//buildtools/third_party/libc++/trunk/include/experimental/iterator",
+  "//buildtools/third_party/libc++/trunk/include/experimental/list",
+  "//buildtools/third_party/libc++/trunk/include/experimental/map",
+  "//buildtools/third_party/libc++/trunk/include/experimental/memory_resource",
+  "//buildtools/third_party/libc++/trunk/include/experimental/propagate_const",
+  "//buildtools/third_party/libc++/trunk/include/experimental/regex",
+  "//buildtools/third_party/libc++/trunk/include/experimental/set",
+  "//buildtools/third_party/libc++/trunk/include/experimental/simd",
+  "//buildtools/third_party/libc++/trunk/include/experimental/string",
+  "//buildtools/third_party/libc++/trunk/include/experimental/type_traits",
+  "//buildtools/third_party/libc++/trunk/include/experimental/unordered_map",
+  "//buildtools/third_party/libc++/trunk/include/experimental/unordered_set",
+  "//buildtools/third_party/libc++/trunk/include/experimental/utility",
+  "//buildtools/third_party/libc++/trunk/include/experimental/vector",
+  "//buildtools/third_party/libc++/trunk/include/ext/__hash",
+  "//buildtools/third_party/libc++/trunk/include/ext/hash_map",
+  "//buildtools/third_party/libc++/trunk/include/ext/hash_set",
+  "//buildtools/third_party/libc++/trunk/include/fenv.h",
+  "//buildtools/third_party/libc++/trunk/include/filesystem",
+  "//buildtools/third_party/libc++/trunk/include/float.h",
+  "//buildtools/third_party/libc++/trunk/include/format",
+  "//buildtools/third_party/libc++/trunk/include/forward_list",
+  "//buildtools/third_party/libc++/trunk/include/fstream",
+  "//buildtools/third_party/libc++/trunk/include/functional",
+  "//buildtools/third_party/libc++/trunk/include/future",
+  "//buildtools/third_party/libc++/trunk/include/initializer_list",
+  "//buildtools/third_party/libc++/trunk/include/inttypes.h",
+  "//buildtools/third_party/libc++/trunk/include/iomanip",
+  "//buildtools/third_party/libc++/trunk/include/ios",
+  "//buildtools/third_party/libc++/trunk/include/iosfwd",
+  "//buildtools/third_party/libc++/trunk/include/iostream",
+  "//buildtools/third_party/libc++/trunk/include/istream",
+  "//buildtools/third_party/libc++/trunk/include/iterator",
+  "//buildtools/third_party/libc++/trunk/include/latch",
+  "//buildtools/third_party/libc++/trunk/include/limits",
+  "//buildtools/third_party/libc++/trunk/include/limits.h",
+  "//buildtools/third_party/libc++/trunk/include/list",
+  "//buildtools/third_party/libc++/trunk/include/locale",
+  "//buildtools/third_party/libc++/trunk/include/locale.h",
+  "//buildtools/third_party/libc++/trunk/include/map",
+  "//buildtools/third_party/libc++/trunk/include/math.h",
+  "//buildtools/third_party/libc++/trunk/include/memory",
+  "//buildtools/third_party/libc++/trunk/include/module.modulemap",
+  "//buildtools/third_party/libc++/trunk/include/mutex",
+  "//buildtools/third_party/libc++/trunk/include/new",
+  "//buildtools/third_party/libc++/trunk/include/numbers",
+  "//buildtools/third_party/libc++/trunk/include/numeric",
+  "//buildtools/third_party/libc++/trunk/include/optional",
+  "//buildtools/third_party/libc++/trunk/include/ostream",
+  "//buildtools/third_party/libc++/trunk/include/queue",
+  "//buildtools/third_party/libc++/trunk/include/random",
+  "//buildtools/third_party/libc++/trunk/include/ratio",
+  "//buildtools/third_party/libc++/trunk/include/regex",
+  "//buildtools/third_party/libc++/trunk/include/scoped_allocator",
+  "//buildtools/third_party/libc++/trunk/include/semaphore",
+  "//buildtools/third_party/libc++/trunk/include/set",
+  "//buildtools/third_party/libc++/trunk/include/setjmp.h",
+  "//buildtools/third_party/libc++/trunk/include/shared_mutex",
+  "//buildtools/third_party/libc++/trunk/include/span",
+  "//buildtools/third_party/libc++/trunk/include/sstream",
+  "//buildtools/third_party/libc++/trunk/include/stack",
+  "//buildtools/third_party/libc++/trunk/include/stdbool.h",
+  "//buildtools/third_party/libc++/trunk/include/stddef.h",
+  "//buildtools/third_party/libc++/trunk/include/stdexcept",
+  "//buildtools/third_party/libc++/trunk/include/stdint.h",
+  "//buildtools/third_party/libc++/trunk/include/stdio.h",
+  "//buildtools/third_party/libc++/trunk/include/stdlib.h",
+  "//buildtools/third_party/libc++/trunk/include/streambuf",
+  "//buildtools/third_party/libc++/trunk/include/string",
+  "//buildtools/third_party/libc++/trunk/include/string.h",
+  "//buildtools/third_party/libc++/trunk/include/string_view",
+  "//buildtools/third_party/libc++/trunk/include/strstream",
+  "//buildtools/third_party/libc++/trunk/include/system_error",
+  "//buildtools/third_party/libc++/trunk/include/tgmath.h",
+  "//buildtools/third_party/libc++/trunk/include/thread",
+  "//buildtools/third_party/libc++/trunk/include/tuple",
+  "//buildtools/third_party/libc++/trunk/include/type_traits",
+  "//buildtools/third_party/libc++/trunk/include/typeindex",
+  "//buildtools/third_party/libc++/trunk/include/typeinfo",
+  "//buildtools/third_party/libc++/trunk/include/unordered_map",
+  "//buildtools/third_party/libc++/trunk/include/unordered_set",
+  "//buildtools/third_party/libc++/trunk/include/utility",
+  "//buildtools/third_party/libc++/trunk/include/valarray",
+  "//buildtools/third_party/libc++/trunk/include/variant",
+  "//buildtools/third_party/libc++/trunk/include/vector",
+  "//buildtools/third_party/libc++/trunk/include/version",
+  "//buildtools/third_party/libc++/trunk/include/wchar.h",
+  "//buildtools/third_party/libc++/trunk/include/wctype.h",
+]
+
+libcxx_licenses = [ "//buildtools/third_party/libc++/trunk/LICENSE.TXT" ]

filenames.libcxxabi.gni

@@ -0,0 +1,6 @@
+libcxxabi_headers = [
+  "//buildtools/third_party/libc++abi/trunk/include/__cxxabi_config.h",
+  "//buildtools/third_party/libc++abi/trunk/include/cxxabi.h",
+]
+
+libcxxabi_licenses = [ "//buildtools/third_party/libc++abi/trunk/LICENSE.TXT" ]

patches/chromium/.patches

@@ -101,3 +101,4 @@ fix_expose_decrementcapturercount_in_web_contents_impl.patch
 add_setter_for_browsermainloop_result_code.patch
 chore_allow_overriding_of_enable_pak_file_integrity_checks.patch
 make_include_of_stack_trace_h_unconditional.patch
+build_libc_as_static_library.patch

patches/chromium/build_libc_as_static_library.patch

@@ -0,0 +1,46 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: VerteDinde <keeleymhammond@gmail.com>
+Date: Wed, 12 May 2021 13:19:19 -0700
+Subject: build_libc++_as_static_library
+
+Build libc++ as static library to compile and pass
+nan tests
+
+diff --git a/buildtools/third_party/libc++/BUILD.gn b/buildtools/third_party/libc++/BUILD.gn
+index 65f6e8585ad374ad59e7670babfedd2fbdfbaa43..0b1333bc8de626db056567f599be27808e1495e5 100644
+--- a/buildtools/third_party/libc++/BUILD.gn
++++ b/buildtools/third_party/libc++/BUILD.gn
+@@ -32,7 +32,11 @@ config("winver") {
+ if (libcxx_is_shared) {
+   _libcxx_target_type = "shared_library"
+ } else {
+-  _libcxx_target_type = "source_set"
++  if (is_win) {
++    _libcxx_target_type = "source_set"
++  } else {
++    _libcxx_target_type = "static_library"
++  }
+ }
+ target(_libcxx_target_type, "libc++") {
+   # Most things that need to depend on libc++ should do so via the implicit
+@@ -40,6 +44,7 @@ target(_libcxx_target_type, "libc++") {
+   # need to explicitly depend on libc++.
+   visibility = [
+     "//build/config:common_deps",
++    "//electron:libcxx_zip",
+     "//third_party/catapult/devil:devil",
+   ]
+   if (is_linux && !is_chromeos) {
+diff --git a/buildtools/third_party/libc++abi/BUILD.gn b/buildtools/third_party/libc++abi/BUILD.gn
+index 8b1da01ce87ff6db8e67938d4c083312cfa3101f..1668eba70db1933a434709c0140fe125991249b3 100644
+--- a/buildtools/third_party/libc++abi/BUILD.gn
++++ b/buildtools/third_party/libc++abi/BUILD.gn
+@@ -4,7 +4,7 @@
+ 
+ import("//build/config/c++/c++.gni")
+ 
+-source_set("libc++abi") {
++static_library("libc++abi") {
+   if (export_libcxxabi_from_executables) {
+     visibility = [ "//build/config:executable_deps" ]
+   } else {

patches/nan/.patches

@@ -1 +1,2 @@
 api_simplify_scriptorigin.patch
+nan_string_test_alignment.patch

patches/nan/nan_string_test_alignment.patch

@@ -0,0 +1,22 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: clavin <clavin@electronjs.org>
+Date: Wed, 12 May 2021 12:43:07 -0600
+Subject: nan_string_test_alignment
+
+Modifies a NAN test to avoid a debug check pertaining to efficient string alignment.
+
+diff --git a/test/cpp/strings.cpp b/test/cpp/strings.cpp
+index 95edeac91a4ec6a5f5cd80aa36dca8a55eb53f2a..0ad5cb7095490ac1eb454318582a9a683cb14be1 100644
+--- a/test/cpp/strings.cpp
++++ b/test/cpp/strings.cpp
+@@ -26,7 +26,9 @@ NAN_METHOD(EncodeHex) {
+ }
+ 
+ NAN_METHOD(EncodeUCS2) {
+-  info.GetReturnValue().Set(Encode("h\0e\0l\0l\0o\0", 10, UCS2));
++  // This odd declaration is to get the string data aligned to a 2-byte boundary
++  const uint16_t str[] = {'h', 'e', 'l', 'l', 'o'};
++  info.GetReturnValue().Set(Encode(reinterpret_cast<const char*>(str), 10, UCS2));
+ }
+ 
+ Persistent<v8::FunctionTemplate> returnUtf8String_persistent;

script/gen-libc++-filenames.js

@@ -0,0 +1,48 @@
+const fs = require('fs');
+const path = require('path');
+
+const check = process.argv.includes('--check');
+
+function findAllHeaders (basePath) {
+  const allFiles = fs.readdirSync(basePath);
+  const toReturn = [];
+  for (const file of allFiles) {
+    const absPath = path.resolve(basePath, file);
+    if (fs.statSync(absPath).isDirectory()) {
+      toReturn.push(...findAllHeaders(absPath));
+    } else {
+      toReturn.push(absPath);
+    }
+  }
+  return toReturn;
+}
+
+for (const folder of ['libc++', 'libc++abi']) {
+  const prettyName = folder.replace(/\+/g, 'x');
+
+  const libcxxIncludeDir = path.resolve(__dirname, '..', '..', 'buildtools', 'third_party', folder, 'trunk', 'include');
+  const gclientPath = `buildtools/third_party/${folder}/trunk/include`;
+
+  const headers = findAllHeaders(libcxxIncludeDir).map(absPath => path.relative(path.resolve(__dirname, '../..', gclientPath), absPath));
+
+  const content = `${prettyName}_headers = [
+  ${headers.map(f => `"//${path.posix.join(gclientPath, f)}"`).join(',\n  ')},
+]
+
+${prettyName}_licenses = [ "//buildtools/third_party/${folder}/trunk/LICENSE.TXT" ]
+`;
+
+  const filenamesPath = path.resolve(__dirname, '..', `filenames.${prettyName}.gni`);
+
+  if (check) {
+    const currentContent = fs.readFileSync(filenamesPath, 'utf8');
+    if (currentContent !== content) {
+      console.log('currentContent: ', currentContent);
+      console.log('content: ', content);
+      throw new Error(`${prettyName} filenames need to be regenerated, latest generation does not match current file.  Please run node gen-libc++-filenames.js`);
+    }
+  } else {
+    console.log(filenamesPath);
+    fs.writeFileSync(filenamesPath, content);
+  }
+}

script/nan-spec-runner.js

@@ -25,7 +25,43 @@ async function main () {
     npm_config_arch: process.env.NPM_CONFIG_ARCH,
     npm_config_yes: 'true'
   });
-  const { status: buildStatus } = cp.spawnSync(NPX_CMD, ['node-gyp', 'rebuild', '--directory', 'test', '-j', 'max'], {
+
+  const clangDir = path.resolve(BASE, 'third_party', 'llvm-build', 'Release+Asserts', 'bin');
+  const cc = path.resolve(clangDir, 'clang');
+  const cxx = path.resolve(clangDir, 'clang++');
+  const ld = path.resolve(clangDir, 'lld');
+
+  // TODO(ckerr) this is cribbed from read obj/electron/electron_app.ninja.
+  // Maybe it would be better to have this script literally open up that
+  // file and pull cflags_cc from it instead of using bespoke code here?
+  // I think it's unlikely to work; but if it does, it would be more futureproof
+  const cxxflags = [
+    '-std=c++14',
+    '-nostdinc++',
+    '-D_LIBCPP_HAS_NO_VENDOR_AVAILABILITY_ANNOTATIONS', // needed by next line
+    `-isystem"${path.resolve(BASE, 'buildtools', 'third_party', 'libc++', 'trunk', 'include')}"`,
+    `-isystem"${path.resolve(BASE, 'buildtools', 'third_party', 'libc++abi', 'trunk', 'include')}"`,
+    '-fPIC'
+  ].join(' ');
+
+  const ldflags = [
+    '-stdlib=libc++',
+    '-fuse-ld=lld',
+    `-L"${path.resolve(BASE, 'out', `${utils.getOutDir({ shouldLog: true })}`, 'obj', 'buildtools', 'third_party', 'libc++abi')}"`,
+    `-L"${path.resolve(BASE, 'out', `${utils.getOutDir({ shouldLog: true })}`, 'obj', 'buildtools', 'third_party', 'libc++')}"`,
+    '-lc++abi'
+  ].join(' ');
+
+  if (process.platform !== 'win32') {
+    env.CC = cc;
+    env.CFLAGS = cxxflags;
+    env.CXX = cxx;
+    env.LD = ld;
+    env.CXXFLAGS = cxxflags;
+    env.LDFLAGS = ldflags;
+  }
+
+  const { status: buildStatus } = cp.spawnSync(NPX_CMD, ['node-gyp', 'rebuild', '--verbose', '--directory', 'test', '-j', 'max'], {
     env,
     cwd: NAN_DIR,
     stdio: 'inherit'
@@ -48,9 +84,7 @@ async function main () {
   const onlyTests = args.only && args.only.split(',');
 
   const DISABLED_TESTS = [
-    'nannew-test.js',
-    'setcallhandler-test.js', // TODO(jkleinsc) renable once https://github.com/electron/electron/pull/29028 lands
-    'typedarrays-test.js' // TODO(nornagon): https://github.com/electron/electron/issues/28414
+    'nannew-test.js'
   ];
   const testsToRun = fs.readdirSync(path.resolve(NAN_DIR, 'test', 'js'))
     .filter(test => !DISABLED_TESTS.includes(test))

script/release/release.js

@@ -139,6 +139,12 @@ function assetsForVersion (version, validatingRelease) {
     'electron-api.json',
     'electron.d.ts',
     'hunspell_dictionaries.zip',
+    'libcxx_headers.zip',
+    'libcxxabi_headers.zip',
+    `libcxx-objects-${version}-linux-arm64.zip`,
+    `libcxx-objects-${version}-linux-armv7l.zip`,
+    `libcxx-objects-${version}-linux-ia32.zip`,
+    `libcxx-objects-${version}-linux-x64.zip`,
     `ffmpeg-${version}-darwin-x64.zip`,
     `ffmpeg-${version}-darwin-arm64.zip`,
     `ffmpeg-${version}-linux-arm64.zip`,

script/release/uploaders/upload.py

@@ -37,6 +37,8 @@ PDB_NAME = get_zip_name(PROJECT_NAME, ELECTRON_VERSION, 'pdb')
 DEBUG_NAME = get_zip_name(PROJECT_NAME, ELECTRON_VERSION, 'debug')
 TOOLCHAIN_PROFILE_NAME = get_zip_name(PROJECT_NAME, ELECTRON_VERSION,
                                       'toolchain-profile')
+CXX_OBJECTS_NAME = get_zip_name(PROJECT_NAME, ELECTRON_VERSION,
+                                      'libcxx_objects')
 
 
 def main():
@@ -95,6 +97,20 @@ def main():
     shutil.copy2(os.path.join(OUT_DIR, 'debug.zip'), debug_zip)
     upload_electron(release, debug_zip, args)
 
+    # Upload libcxx_objects.zip for linux only
+    libcxx_objects = get_zip_name('libcxx-objects', ELECTRON_VERSION)
+    libcxx_objects_zip = os.path.join(OUT_DIR, libcxx_objects)
+    shutil.copy2(os.path.join(OUT_DIR, 'libcxx_objects.zip'), libcxx_objects_zip)
+    upload_electron(release, libcxx_objects_zip, args)
+
+  # Upload headers.zip and abi_headers.zip as non-platform specific
+  if get_target_arch() == "x64":
+    cxx_headers_zip = os.path.join(OUT_DIR, 'libcxx_headers.zip')
+    upload_electron(release, cxx_headers_zip, args)
+
+    abi_headers_zip = os.path.join(OUT_DIR, 'libcxxabi_headers.zip')
+    upload_electron(release, abi_headers_zip, args)
+
   # Upload free version of ffmpeg.
   ffmpeg = get_zip_name('ffmpeg', ELECTRON_VERSION)
   ffmpeg_zip = os.path.join(OUT_DIR, ffmpeg)