PVS-Studio warning V530 for Nmap

/** Deletes all previous field specifiers.
  * This should be used when dealing
  * with clients that send multiple NEP_PACKET_SPEC messages,
  * so only the last PacketSpec is taken into account. */
int NEPContext::resetClientFieldSpecs(){
  this->fspecs.empty();
  return OP_SUCCESS;
} /* End of resetClientFieldSpecs() */

What a nice comment. It's a pity that the code does quite a different thing.
This is what should have been written here: this->fspecs.clear();

This suspicious code was found in Nmap project by PVS-Studio static code analyzer.
Warning message is:
V530 The return value of function 'empty' is required to be utilized. nping nepcontext.cc 562

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