PVS-Studio warning V517 for Scilab

int sci_xset( char *fname, unsigned long fname_len )
{
  ....
  else if ( strcmp(cstk(l1), "mark size") == 0)
  ....
  else if ( strcmp(cstk(l1), "mark") == 0)
  ....
  ....
  else if ( strcmp(cstk(l1), "mark") == 0)
  ....
  else if ( strcmp(cstk(l1), "colormap") == 0)
  ....
}

This suspicious code was found in Scilab project by PVS-Studio static code analyzer.
Warning message is:
V517 The use of 'if (A) {...} else if (A) {...}' pattern was detected. There is a probability of logical error presence. Check lines: 175, 398. sci_xset.c 175

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