gn analyze output:
{
  "compile_targets": [],
  "status": "No dependency",
  "test_targets": []
}
gn analyze input:
{
  "files": [
    "//libcxx/.clang-format",
    "//libcxx/docs/UserDocumentation.rst",
    "//libcxx/include/__config",
    "//libcxx/include/__mutex/lock_guard.h",
    "//libcxx/include/__mutex/mutex.h",
    "//libcxx/include/mutex",
    "//libcxx/include/shared_mutex",
    "//libcxx/test/libcxx/thread/thread.mutex/thread_safety_annotations_not_enabled.pass.cpp",
    "//libcxx/test/libcxx/thread/thread.mutex/thread_safety_lock_guard.pass.cpp",
    "//libcxx/test/libcxx/thread/thread.mutex/thread_safety_lock_unlock.pass.cpp",
    "//libcxx/test/libcxx/thread/thread.mutex/thread_safety_missing_unlock.verify.cpp",
    "//libcxx/test/libcxx/thread/thread.mutex/thread_safety_requires_capability.pass.cpp",
    "//libcxx/test/libcxx/thread/thread.shared_mutex/thread_safety.verify.cpp",
    "//libcxx/test/libcxx/thread/thread.shared_timed_mutex/thread_safety.verify.cpp",
    "//libcxx/utils/libcxx/test/features.py"
  ],
  "test_targets": [
    "//clang-tools-extra/clangd/test:check-clangd",
    "//clang-tools-extra/test:check-clang-tools",
    "//clang/test:check-clang",
    "//compiler-rt/test/hwasan:check-hwasan",
    "//lld/test:check-lld",
    "//llvm/test:check-llvm"
  ],
  "additional_compile_targets": []
}
running all tests due to change to blacklisted file