[U-Boot] [PATCH] ppc4xx: Enable support for 64bit printf on all PPC4xx variants

Scott Wood
2009-07-08T21:11:02Z

Wolfgang Denk wrote:
>>> I hope we don't have any more such #defines hidden in other header
>>> files?
>> I vote for completely removing these defines then (or at least
>> CONFIG_SYS_64BIT_VSPRINTF) and by this enabling the 64bit printf format for
>> all boards. I myself have hunted problems disguised by incorrect 64bit
>
> I don't want this because of the memory footprint.
>
> Actually I'm pretty much annoyed we need this at all.

Note that the overhead of 64-bit printf (assuming the 64-bit
divide/remainder functions in libgcc aren't pulled in for anything else)
is 2524 bytes on powerpc (using GCC 4.3.2). That's less than NFS,
which gets turned on by default (as was brought up recently). :-)

What if we were to invert the option (CONFIG_SYS_NO_64BIT_VSPRINTF) so
that it would only be disabled on boards at the intersection of tight
space constraints and a board maintainer who's pretty sure this board
doesn't need it? There could also be some warning from printf() if %ll
is used when not supported, and/or it could still check for %ll and pop
a long long from the varargs but discard the high half.

-Scott