PVS-Studio warning V547 for Prime95

BOOL CPrime95App::InitInstance()
{
  char *p;
  ....
  for (p = m_lpCmdLine; *p == '//' || *p == '-'; ) {
  ....
}

This suspicious code was found in Prime95 project by PVS-Studio static code analyzer.
Warning message is:
V547 Expression '* p == '//'' is always false. The value range of char type: [-128, 127]. prime95 prime95.cpp 156

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