问题描述：
源码编译安装pytorch时执行git submodule update --init报错如下：
Submodule path ‘third_party/protobuf’: checked out ‘48cb18e5c419ddd23d9badcfe4e9df7bde1979b2’
Submodule ‘third_party/benchmark’ (https://github.com/google/benchmark.git) registered for path ‘third_party/benchmark’
Submodule ‘third_party/googletest’ (https://github.com/google/googletest.git) registered for path ‘third_party/googletest’
Cloning into ‘third_party/benchmark’…
fatal: unable to access ‘https://github.com/google/benchmark.git/’: gnutls_handshake() failed: Error in the pull function.
fatal: clone of ‘https://github.com/google/benchmark.git’ into submodule path ‘third_party/benchmark’ failed
Failed to recurse into submodule path ‘third_party/protobuf’
解决方法
rm -fr third_party/
git submodule update --init --recursive
