Re: configure.in support for FreeBSD ia64/sparc64/powerpc

[Giorgos Keramidas <keramida@ceid.upatras.gr>]

On 2006-11-03 22:28, Chong Yidong <cyd@stupidchicken.com> wrote:
>Giorgos Keramidas <keramida@ceid.upatras.gr> writes:
>> The following change makes Emacs buildable on FreeBSD running on
>> sparc64, ia64 and powerpc too.  It has been tested for some time as a
>> local patch in the editors/emacs-devel port of FreeBSD, so it would be
>> nice if it became part of Emacs 22.  We won't have to maintain local
>> diffs for this part then:
>>
>> --- a/src/alloc.c	Fri Oct 27 15:45:51 2006 +0000
>> +++ b/src/alloc.c	Sat Oct 28 01:49:45 2006 +0300
>> @@ -4560,7 +4560,11 @@ mark_stack ()
>>       needed on ia64 too.  See mach_dep.c, where it also says inline
>>       assembler doesn't work with relevant proprietary compilers.  */
>>  #ifdef sparc
>> +#ifdef __sparc64__
>> +  asm ("flushw");
>> +#else
>>    asm ("ta 3");
>> +#endif
>>  #endif
> 
> Is this change correct for non-FreeBSD sparc64 systems too?  (I don't
> know anything about this part of the code.)

Sorry for taking so long to follow up about this.  I tried looking at
the sparc v9 specification for hints about why this change is needed on
64-bit SPARC platforms, but I couldn't come up with anything in a
reasonable amount of time.  I am not that proficient with SPARC64
assembly, but I will ask our FreeBSD/sparc64 people for details.

I'll follow up again when I get a reply from the people who know more
about sparc64 assembly :)

In the mean time, I can maintain this as a local FreeBSD patch, so it's
not really something we should push hard for getting into the release.