[U-Boot-Users] PATCH for cmd_mem.c:do_mem_mtest()
Jerry Van Baren
gerald.vanbaren at smiths-aerospace.com
Tue Sep 13 22:08:39 CEST 2005
Wolfgang Denk wrote:
> In message <43271DD7.1050003 at smiths-aerospace.com> you wrote:
>
>>> #define CFG_MEMTEST_SCRATCH (--end)
>
> ...
>
>>I'm not sure you want that, exactly. You are affecting the variable
>>"end" as a side effect in a macro which is generally a bad idea. A no
>>side effect version would be:
>>#define CFG_MEMTEST_SCRATCH (end - 1)
>
>
> That would mean that *end is included in testing, and used as scratch
> cell at the same time --> will not work.
>
>
>>You are also making assumptions on the type of end (the variable, that
>
>
> No. Just, that it has the same type as the "dummy" variable
> initilaized by CFG_MEMTEST_SCRATCH
>
>
>>#define CFG_MEMTEST_SCRATCH ((void *)end - 1)
>
>
> That would be definitely worse.
>
> Best regards,
>
> Wolfgang Denk
Ahh, you _did_ intend the side effect. You are being trickier than I
gave you credit for. Please disregard my interference...
gvb
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