Post by Marcus Meissner(forwarding for Peter, as he is not subscribed here).
Any comments?
Ciao, Marcus
Date: 20. April 2010 17:55:39 MESZ
Subject: Re: [Bug 596271] glibc 2.11 being built without support to "old" powerpc32 processors (G4)
http://bugzilla.novell.com/show_bug.cgi?id=596271
http://bugzilla.novell.com/show_bug.cgi?id=596271#c3
%define enable_stackguard_randomization 1
-%ifarch ppc ppc64
+%ifarch ppc64
%define optimize_power 1
Do you think this is acceptable for openSUSE? I don't want to propose a change
that will cause performance degradation for the majority of users (assuming
that most openSUSE ppc users have IBM hardware and not Apple) and benefit only
myself :)
I would like to get opinion of other ppc users if there are any.
We can either disable -mcpu=power4 which will make it work on G4
as well but have non-trivial performance impact (I don't have any
figures), or decide G4 is unsupported. There are also compromises
like having /lib/power4/libc.so that should be easy to do with our
glibc.spec, but will require extra building time and I don't have
the time to implement this myself.
If there will be no clear feedback, I will drop -mcpu=power4.
The G4 is the most recent 32 bit PowerPC available. It's called e600 now, but basically the same technology from back then.
For ppc64 I'd actually think it'd make sense to move ahead with ppc64 userland as well. So making POWER4 and above fast there just doesn't make any sense.
IOW yes, please disable -mcpu=power4 for ppc(32).
As far as the /lib/power4 directory goes - that's exactly what 11.1 does for me:
lychee:~/:[0]# l /lib/power4/
total 2500
drwxr-xr-x 2 root root 4096 Feb 17 2009 ./
drwxr-xr-x 23 root root 12288 Jan 16 14:20 ../
-rwxr-xr-x 2 root root 1583356 Jan 22 2009 libc-2.9.so*
lrwxrwxrwx 1 root root 11 Feb 17 2009 libc.so.6 -> libc-2.9.so*
-rwxr-xr-x 1 root root 731660 Jan 22 2009 libm-2.9.so*
lrwxrwxrwx 1 root root 11 Feb 17 2009 libm.so.6 -> libm-2.9.so*
-rwxr-xr-x 2 root root 133332 Jan 22 2009 libpthread-2.9.so*
lrwxrwxrwx 1 root root 17 Feb 17 2009 libpthread.so.0 -> libpthread-2.9.so*
-rwxr-xr-x 2 root root 39128 Jan 22 2009 librt-2.9.so*
lrwxrwxrwx 1 root root 12 Feb 17 2009 librt.so.1 -> librt-2.9.so*
-rwxr-xr-x 1 root root 34848 Jan 22 2009 libthread_db-1.0.so*
lrwxrwxrwx 1 root root 19 Feb 17 2009 libthread_db.so.1 -> libthread_db-1.0.so*
lychee:~/:[0]# rpm -qf /lib/power4/libc-2.9.so
glibc-2.9-2.10.1
Alex