[U-Boot] [PATCH v2] arm: Correct build error introduced by getenv_ulong() patch

[Detlev Zundel]

Hi Mike,

> On Monday 31 October 2011 17:06:46 Simon Glass wrote:
>> On Sun, Oct 30, 2011 at 5:44 PM, Mike Frysinger wrote:
>> > On Sunday 23 October 2011 23:44:35 Simon Glass wrote:
>> >> --- a/arch/arm/lib/board.c
>> >> +++ b/arch/arm/lib/board.c
>> >> 
>> >>       flash_size = flash_init();
>> >>       if (flash_size > 0) {
>> >>  # ifdef CONFIG_SYS_FLASH_CHECKSUM
>> >> +             char *s = getenv("flashchecksum");
>> >> +
>> >>               print_size(flash_size, "");
>> >>               /*
>> >>                * Compute and print flash CRC if flashchecksum is set to
>> >> 'y' *
>> >>                * NOTE: Maybe we should add some WATCHDOG_RESET()? XXX
>> >>                */
>> >> -             s = getenv("flashchecksum");
>> >>               if (s && (*s == 'y')) {
>> >>                       printf("  CRC: %08X", crc32(0,
>> >>                               (const unsigned char *)
>> >> CONFIG_SYS_FLASH_BASE, @@ -566,9 +567,12 @@ void board_init_r(gd_t *id,
>> >> ulong dest_addr) /* Initialize from environment */
>> >>       load_addr = getenv_ulong("loadaddr", 16, load_addr);
>> >>  #if defined(CONFIG_CMD_NET)
>> >> -     s = getenv("bootfile");
>> >> -     if (s != NULL)
>> >> -             copy_filename(BootFile, s, sizeof(BootFile));
>> >> +     {
>> >> +             char *s = getenv("bootfile");
>> >> +
>> >> +             if (s != NULL)
>> >> +                     copy_filename(BootFile, s, sizeof(BootFile));
>> >> +     }
>> >>  #endif
>> > 
>> > seems like a better solution would be to use at the top:
>> >        __maybe_unused char *s;
>> > 
>> > also, shouldn't these be "const char *s" ?
>> 
>> We can certainly do this and I agree it is easier than #ifdefs. Does
>> it introduce the possibility that one day the code will stop using the
>> variable but it will still be declared? Is the fact that we need the
>> #ifdefs an indication that the function should be too long and should
>> be refactored? it in fact better to have these explicit so we can see
>> them for the ugliness they are?
>
> yes, you're right that it does leave the door open to the variable being 
> declared, never used, and gcc not emitting a warning about it.
>
> both setups suck, but i'd lean towards the less-ifdef state ... wonder if 
> Wolfgang has a preference.

Personally, I think that the nuisance of a potential unused variable is
less of an issue than the actual _problems_ that ifdefs induce.

Cheers
  Detlev

-- 
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