Getting rid of -fno-unit-at-a-time [Was Re: RFC: Preserving order of functions and top-level asms via cgraph]

[Daniel Kegel]

Andi Kleen wrote:
> Daniel Jacobowitz <drow@false.org> writes:
> 
> 
>>On Mon, Apr 11, 2005 at 10:02:06AM -0700, Daniel Kegel wrote:
>>
>>>BTW, I hope -fno-unit-at-a-time doesn't go away until at least gcc-4.1.1
>>>or so... I still lean on that crutch.
>>
>>A user!  Can you explain why?
> 
> 
> The x86-64 2.4 linux kernel uses it too, because some code relies on 
> the ordering between asm and several functions.
> Other Linux ports might be similarly affected. 2.6 is fixed, but the
> fix is a bit too big to merge into a stable-nearly-dead tree like 2.4.

Last I checked, the live cvs tree for glibc
still used  -fno-unit-at-a-time.  Maybe Jakub can comment on
the timetable for getting rid of -fno-unit-at-a-time.

(And even if glibc-2.4.0 no longer needs -fno-unit-at-a-time,
there will still be people who want to build
oldish glibc's with new gcc's.  I tend to sympathize
with them, and explicitly support building gcc-4.0/glibc toolchains
with glibc-2.1.3 and up in crosstool.  Yeah, crosstool's a
bit obsessive -- there's no real reason to use the same gcc
for glibc as for user programs -- but it's simpler than
building an older gcc just to build glibc.)
- Dan