On Tuesday, February 26, 2002, at 06:55 AM, Ralf Baechle wrote:
> On Tue, Feb 26, 2002 at 12:10:50AM -0500, Jay Carlson wrote:
>
>> By default non-PIC code *does* use $gp due to the brain damage in gas;
>> gas defaults to -G 8 unless told otherwise (-KPIC implies -G0 so we
>> don't see this in PIC code.) gcc won't know anything about this, of
>> course.
>>
>> What I'm doing in SUBTARGET_ASM_SPEC is to write something like
>> "%{fno-pic: %{!G: -G0}}"--if we're not in PIC mode, pass -G0 to gas by
>> default.
>>
>> Anyway, once that's straightened out, -G8 does appear to work the way
>> you'd expect, with the code that Hartvig pasted above---I had written a
>> byte-for-byte identical patch :-)
>
> I agree on that one except that 64kB of small data no longer seem to be
> sufficient for every common application in the world. So I'd vote for a
> more defensive choice of the -G value, that is 0.
Right. In my ideal world, here's how it would work:
cc1 defaults to -G0. I think we have that now.
gas defaults to -G0. Messing with SUBTARGET_ASM_SPEC has that effect
for people who use the gcc driver, but anybody invoking gas directly
will still hit this problem, but too bad.
So I think the primary constituency for gas defaulting to -G8 are
existing cygnuhhhh I mean redhat embedded MIPS customers, outside of
Linux; that's who we should check with before we change the default.
Jay
