PVS-Studio warning V666 for TPP

int main(int argc, char** argv) {
  ....
  if (strcmp(argv[argidx], "NONSS") &&
      ....
      strncmp(argv[argidx], "CAT=", 4) &&
      strncmp(argv[argidx], "DECOY=", 6) &&
      strncmp(argv[argidx], "THREADS=", 6) &&
      strncmp(argv[argidx], "MINPROB=", 8)) {
  ....
}

This suspicious code was found in TPP project by PVS-Studio static code analyzer.
Warning message is:
V666 Consider inspecting third argument of the function 'strncmp'. It is possible that the value does not correspond with the length of a string which was passed with the second argument. interprophetmain.cxx 151

PVS-Studio is a static analyzer for detecting bugs in the source code of applications written in C, C++, C++11, C++/CX. Site: http://www.viva64.com/en/pvs-studio/