PVS-Studio warning V649 for Miranda IM

int CLUIFramesGetalClientFrame(void)
{
  int i;

  if(alclientFrame!=-1)
    return alclientFrame;

  if(alclientFrame!=-1)
  {
    /* this value could become invalid if RemoveItemFromList
     * was called, so we double-check */
    ....
  }
}

This suspicious code was found in Miranda IM project by PVS-Studio static code analyzer.
Warning message is:
V649 There are two 'if' statements with identical conditional expressions. The first 'if' statement contains function return. This means that the second 'if' statement is senseless. Check lines: 693, 696. cluiframes.c 696

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