Jack Howarth wrote:

> Ortho.c: In function 'OrthoFree':
> Ortho.c:1973: warning: array subscript is above array bounds

> #define CMD_QUEUE_MASK 0x3

>    CQueue *cmdQueue[CMD_QUEUE_MASK+1];

>     int a;
> 
>     for(a=0;a<=CMD_QUEUE_MASK;a++)
>       ;
>     I->cmdQueue[a] = ((void *)0);
> }
> 
> which produces the warning...
> 
> test.c: In function ‘OrthoFree’:
> test.c:24: warning: array subscript is above array bounds
> 
> ...for the last assignment of I->cmdQueue[a] = ((void *)0).
> It would seem to me that 'a' should be CMD_QUEUE_MASK+1
> on exiting the for statement so that the assignment should
> be valid. 

  Am I tired or are you?  This looks like a typical off-by-one in the code to
me.  CMD_QUEUE_MASK is 0x3, meaning that the array is cmdQueue[4], consisting
of entries numbered 0 ... 3.  The loop exits when is no longer <= 3, i.e. a ==
4.  That's not a valid index between 0 and 3.

  OTOH it is 4am over here and I could be blind.  I'll just go over here now
and zzzzzzzzzzzzzzzzzzzzzzzZZZZZZSNRK

    cheers,
      DaveK

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