build error

[0xKira]

The error message:

==> Upgrading 1 outdated package:
twlz0ne/ccls/ccls 0.20180924 -> 0.20181225.8
==> Upgrading twlz0ne/ccls/ccls
==> Cloning https://github.com/MaskRay/ccls.git
Updating /Users/kira/Library/Caches/Homebrew/ccls--git
==> Checking out tag 0.20181225.8
HEAD is now at d275ed5 textDocument/didOpen: index related files when a header is opened
HEAD is now at d275ed5 textDocument/didOpen: index related files when a header is opened
Entering 'third_party/rapidjson'
Synchronizing submodule url for 'thirdparty/gtest'
Entering 'third_party/rapidjson/thirdparty/gtest'
/Users/kira/Library/Caches/Homebrew/ccls--git/third_party/rapidjson
/Users/kira/Library/Caches/Homebrew/ccls--git/third_party/rapidjson/thirdparty/gtest
==> cmake -DCMAKE_C_FLAGS_RELEASE=-DNDEBUG -DCMAKE_CXX_FLAGS_RELEASE=-DNDEBUG -D
==> cmake --build Release --target install
Last 15 lines from /Users/kira/Library/Logs/Homebrew/ccls/02.cmake:
  "vtable for clang::IgnoringDiagConsumer", referenced from:
      clang::IgnoringDiagConsumer::IgnoringDiagConsumer() in clang_tu.cc.o
      clang::IgnoringDiagConsumer::IgnoringDiagConsumer() in project.cc.o
  NOTE: a missing vtable usually means the first non-inline virtual member function has no definition.
  "vtable for clang::vfs::FileSystem", referenced from:
      clang::vfs::FileSystem::FileSystem() in sema_manager.cc.o
  NOTE: a missing vtable usually means the first non-inline virtual member function has no definition.
  "vtable for clang::index::IndexDataConsumer", referenced from:
      clang::index::IndexDataConsumer::IndexDataConsumer() in indexer.cc.o
  NOTE: a missing vtable usually means the first non-inline virtual member function has no definition.
ld: symbol(s) not found for architecture x86_64
clang-7: error: linker command failed with exit code 1 (use -v to see invocation)
make[2]: *** [ccls] Error 1
make[1]: *** [CMakeFiles/ccls.dir/all] Error 2
make: *** [all] Error 2

If reporting this issue please do so at (not Homebrew/brew or Homebrew/core):
https://github.com/twlz0ne/homebrew-ccls/issues

[twlz0ne]

• Did you tried brew doctor?
• What is the output of brew config?

[0xKira]

I manually fixed the warnings of brew doctor and the error is still there.
Here is the output of brew config:

HOMEBREW_VERSION: 2.0.2-76-g32d1c68
ORIGIN: https://github.com/Homebrew/brew
HEAD: 32d1c688adda389704cb74ce8acd43cb1874c0a4
Last commit: 11 minutes ago
Core tap ORIGIN: https://github.com/Homebrew/homebrew-core.git
Core tap HEAD: d93a16f7e98a0f4b35248fde100486c82313823a
Core tap last commit: 3 hours ago
HOMEBREW_PREFIX: /usr/local
HOMEBREW_DEV_CMD_RUN: 1
HOMEBREW_LOGS: /Users/kira/Library/Logs/Homebrew
HOMEBREW_NO_AUTO_UPDATE: 1
CPU: quad-core 64-bit kabylake
Homebrew Ruby: 2.3.7 => /System/Library/Frameworks/Ruby.framework/Versions/2.3/usr/bin/ruby
Clang: 10.0 build 1000
Git: 2.20.1 => /usr/local/bin/git
Curl: 7.54.0 => /usr/bin/curl
Java: 1.8.0_152
macOS: 10.14.3-x86_64
CLT: 10.1.0.0.1.1539992718
Xcode: 10.1