title: Could NOT find Protobuf (missing: Protobuf_PROTOC_EXECUTABLE)
body: <p>When I am doing a cmake in the build directory of the project I am getting this error. Initially I got a</p>
  
  <blockquote>
    <p>protobuf-config.cmake not found</p>
  </blockquote>
  
  <p>error. So I gave a path of the protobuf-config.cmake file to Protobuf_DIR. Later it started to show this new error:</p>
  
  <blockquote>
    <p>CMake Error at
    /opt/cmake/share/cmake-3.13/Modules/FindPackageHandleStandardArgs.cmake:137
    (message):   Could NOT find Protobuf (missing:
    Protobuf_PROTOC_EXECUTABLE) </p>
    
    <p>(found   suitable version "3.6.1", minimum required is "3.0.0")</p>
  </blockquote>
  
  <p>I am also attaching the error log file:
  <a href="https://drive.google.com/open?id=1y7BZ6lDBtxvla7r-o188xM_FjwLqwhCx" rel="noreferrer">https://drive.google.com/open?id=1y7BZ6lDBtxvla7r-o188xM_FjwLqwhCx</a></p>
  
  <p>I am doing this on Ubuntu-18 with cmake version: 3.13 and protobuf version: 3.6.1   </p>