```
LINK ./unittests
FAILED: unittests
TOOL_VERSION=1606820901 ../../build/toolchain/mac/linker_driver.py -Wcrl,strippath,/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/strip ../../third_party/llvm-build/Release+Asserts/bin/clang++ -B /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/ -Wl,-fatal_warnings -stdlib=libc++ -arch x86_64 -Werror -nostdlib++ -isysroot ../../../../../../../../Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX11.0.sdk -mmacosx-version-min=10.10.0 -Wl,-ObjC -Wl,-rpath,@loader_path/. -Wl,-rpath,@loader_path/../../.. -o "./unittests" -Wl,-filelist,"./unittests.rsp" ./libv8_for_testing.dylib ./libv8_libbase.dylib ./libv8_libplatform.dylib ./libicui18n.dylib ./libicuuc.dylib ./libv8_cppgc_shared_for_testing.dylib ./libc++.dylib
ld: warning: direct access in function 'testing::internal::SuiteApiResolver<testing::internal::(anonymous namespace)::FailureTest>::GetSetUpCaseOrSuite(char const*, int)' from file 'obj/third_party/googletest/gtest/gtest.o' to global weak symbol 'testing::Test::SetUpTestSuite()' from file 'obj/test/unittests/unittests_sources/access-check-unittest.o' means the weak symbol cannot be overridden at runtime. This was likely caused by different translation units being compiled with different visibility settings.
ld: warning: direct access in function 'testing::internal::SuiteApiResolver<testing::internal::(anonymous namespace)::FailureTest>::GetSetUpCaseOrSuite(char const*, int)' from file 'obj/third_party/googletest/gtest/gtest.o' to global weak symbol 'testing::Test::SetUpTestCase()' from file 'obj/test/unittests/unittests_sources/access-check-unittest.o' means the weak symbol cannot be overridden at runtime. This was likely caused by different translation units being compiled with different visibility settings.
ld: warning: direct access in function 'testing::internal::SuiteApiResolver<testing::internal::(anonymous namespace)::FailureTest>::GetTearDownCaseOrSuite(char const*, int)' from file 'obj/third_party/googletest/gtest/gtest.o' to global weak symbol 'testing::Test::TearDownTestSuite()' from file 'obj/test/unittests/unittests_sources/access-check-unittest.o' means the weak symbol cannot be overridden at runtime. This was likely caused by different translation units being compiled with different visibility settings.
ld: warning: direct access in function 'testing::internal::SuiteApiResolver<testing::internal::(anonymous namespace)::FailureTest>::GetTearDownCaseOrSuite(char const*, int)' from file 'obj/third_party/googletest/gtest/gtest.o' to global weak symbol 'testing::Test::TearDownTestCase()' from file 'obj/test/unittests/unittests_sources/access-check-unittest.o' means the weak symbol cannot be overridden at runtime. This was likely caused by different translation units being compiled with different visibility settings.
ld: fatal warning(s) induced error (-fatal_warnings)
clang: error: linker command failed with exit code 1 (use -v to see invocation)
aaa
Traceback (most recent call last):
File "../../build/toolchain/mac/linker_driver.py", line 307, in <module>
Main(sys.argv)
File "../../build/toolchain/mac/linker_driver.py", line 97, in Main
subprocess.check_call(compiler_driver_args, env=env)
File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/subprocess.py", line 190, in check_call
raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['../../third_party/llvm-build/Release+Asserts/bin/clang++', '-B', '/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/', '-Wl,-fatal_warnings', '-stdlib=libc++', '-arch', 'x86_64', '-Werror', '-nostdlib++', '-isysroot', '../../../../../../../../Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX11.0.sdk', '-mmacosx-version-min=10.10.0', '-Wl,-ObjC', '-Wl,-rpath,@loader_path/.', '-Wl,-rpath,@loader_path/../../..', '-o', './unittests', '-Wl,-filelist,./unittests.rsp', './libv8_for_testing.dylib', './libv8_libbase.dylib', './libv8_libplatform.dylib', './libicui18n.dylib', './libicuuc.dylib', './libv8_cppgc_shared_for_testing.dylib', './libc++.dylib']' returned non-zero exit status 1
[26/27] LIBTOOL-STATIC obj/libwee8.a
ninja: build stopped: subcommand failed.
Error! - V8 compilation finished with errors.
```