Fail to install llvm/clang on debian

Hello,
  Maybe this is not a bugs. But i fail to install llvm many times and different machine(debian os).
  First, i follow the instruction:

  http://cilium.readthedocs.io/en/latest/bpf/#llvm

  But during in compiling, i alway get:
  ...
  /home/yubo/git/llvm/tools/clang/lib/Basic/VirtualFileSystem.cpp: In member function ‘virtual llvm::ErrorOr<std::unique_ptr<clang::vfs::File> > {anonymous}::RealFileSystem::openFileForRead(const llvm::Twine&)’:
  /home/yubo/git/llvm/tools/clang/lib/Basic/VirtualFileSystem.cpp:262:46: error: ‘OF_None’ is not a member of ‘llvm::sys::fs’ sys::fs::openFileForRead(Name, FD, sys::fs::OF_None, &RealName))

  [ 75%] Building CXX object tools/clang/lib/Rewrite/CMakeFiles/clangRewrite.dir/HTMLRewrite.cpp.o
  tools/clang/lib/Basic/CMakeFiles/clangBasic.dir/build.make:1244: recipe for target 'tools/clang/lib/Basic/CMakeFiles/clangBasic.dir/VirtualFileSystem.cpp.o' failed
  make[2]: *** [tools/clang/lib/Basic/CMakeFiles/clangBasic.dir/VirtualFileSystem.cpp.o] Error 1
  CMakeFiles/Makefile2:12824: recipe for target 'tools/clang/lib/Basic/CMakeFiles/clangBasic.dir/all' failed
  make[1]: *** [tools/clang/lib/Basic/CMakeFiles/clangBasic.dir/all] Error 2
  make[1]: *** 正在等待未完成的任务....
  [ 75%] Building CXX object tools/clang/lib/Rewrite/CMakeFiles/clangRewrite.dir/Rewr
                           Even thought i follow install instructions from llvm home-page, i get it simliar.What am i missing?
  kernel version:4.17.0-rc7+
  cmake -version cmake version 3.7.2
  gcc version 6.3.0 20170516 (Debian 6.3.0-18+deb9u1)
  debian os

  Thank you in advance.

  Please cc me i am not subscribe the lists, thx!

Hi,

It looks like "OF_None" was only added in the last day or so. The most
likely problem is that your Clang and LLVM checkouts aren't
synchronized properly. Have you tried updating them?

Cheers.

Tim.

Hello, sorry for later reply.

Hi,

It looks like "OF_None" was only added in the last day or so. The most
likely problem is that your Clang and LLVM checkouts aren't
synchronized properly. Have you tried updating them?

Em. Yes. After your hint, i re-git-clone the llvm && clang.It works!
Thank you.