title: Failed to build Dockerfile.devel with error -Werror=maybe-uninitialized
body: <p>I am building tensorflow-server from source code, <a href="https://github.com/tensorflow/serving/blob/master/tensorflow_serving/g3doc/building_with_docker.md" rel="nofollow noreferrer">refer to doc</a>, but it was failed.</p>
  
  <p>My environment:
  Linux 3.10.0-1062.12.1.el7.x86_64 
  Docker 19.03.8</p>
  
  <p>Build command:</p>
  
  <pre><code>docker build --pull -t $USER/tensorflow-serving-devel   -f tensorflow_serving/tools/docker/Dockerfile.devel
  </code></pre>
  
  <p>Error output:</p>
  
  <pre><code>ERROR: /root/.cache/bazel/_bazel_root/e53bbb0b0da4e26d24b415310219b953/external/upb/BUILD:57:1: C++ compilation of rule '@upb//:upb' failed (Exit 1)
  external/upb/upb/table.c: In function 'upb_inttable_pop':
  external/upb/upb/table.c:588:10: error: 'val.val' may be used uninitialized in this function [-Werror=maybe-uninitialized]
     return val;
            ^~~
  cc1: all warnings being treated as errors
  Target //tensorflow_serving/model_servers:tensorflow_model_server failed to build
  INFO: Elapsed time: 592.958s, Critical Path: 122.61s
  INFO: 3550 processes: 3550 local.
  FAILED: Build did NOT complete successfully
  </code></pre>