allow building with older binutils

[loveshack]

#379 was closed without any action, and I don't seem to be able to re-open it.

I've added a NO_VPERMPD switch, like NO_AVX, to allow building 0.2.9 on RHEL6 with the
system binutils. The patch is attached to https://bugzilla.redhat.com/show_bug.cgi?id=1115042
Obviously it needs a documentation addition if you use it.

[tkelman]

Should this perhaps be called NO_AVX2 since presumably vpermpd isn't the only problematic instruction that might be used now or in future openblas kernels?

[wernsaar]

Hi,
@tkelman : I think, that we don't need such a flag. RHEL6 is somewhat outdated, but because I also use CentOS-6 and Rocks-6.1, I have published newer binutils at https://sourceforge.net/projects/slurm-roll/files/addons/6.1.1/rpms/. My rpm package does not replace or overwrite the
default binutils package. You only have to set PATH or to use env-modules.

Best regards
Werner

[xianyi]

@wernsaar , could you add the solution to FAQ or somewhere?

[tkelman]

Does adding such a flag hurt in any way? I personally am still on Red Hat 5, and many others are on Red Hat / CentOS / Scientific Linux 6, often without root access to easily install new software. It would be ideal to allow OpenBLAS to still compile on those systems, preferably without compromising performance too much on Sandy Bridge and Piledriver processors since those kernels aren't using the AVX2 instructions that require the newer binutils.

[wernsaar]

On 03.07.2014 09:11, Zhang Xianyi wrote:

@wernsaar , could you add the solution to FAQ or somewhere?

---

Reply to this email directly or view it on GitHub:
#401 (comment)
Hi,

I added a short description to FAQ.

Best regards
Werner

[xianyi]

@tkelman , thank you for the suggestion.

@wernsaar , I think we need provide NO_AVX2 flag for some old distribution.
I will work on this issue.

[loveshack]

Zhang Xianyi notifications@github.com writes:

@tkelman , thank you for the suggestion.

@wernsaar , I think we need provide NO_AVX2 flag for some old distribution.
I will work on this issue.

Thank you.

I hope you only need to change to the name of the variable in the patch
I sent. It's tested on an RHEL6-compatible system, with a build in
http://copr-be.cloud.fedoraproject.org/results/loveshack/livhpc/epel-6-x86_64/openblas-0.2.9-3liv.el6/.
A build with AVX2 support, using binutils from the re-built devtoolset
that I referred to originally, is in
http://copr-be.cloud.fedoraproject.org/results/loveshack/livhpc/epel-6-x86_64/openblas-0.2.9-3liv2.el6/.

It seems to me best to use the devtoolset packages, especially as you're
likely to want the compiler update for other things. (You don't need
the advertised scl mechanism to use them -- the packaging above just
sets PATH.)

I'll try on RHEL5 when I have a chance, but I don't know of a devtoolset
rebuild for that.

[crayxt]

@loveshack Scientific Linux has a rebuilt devtoolset for 5th version too. The link is http://linuxsoft.cern.ch/cern/devtoolset/slc5X/x86_64/yum/devtoolset

Sometime ago I've managed to setup mock builds and produce binary snapshots of Julia. See the gist with minimal configs https://gist.github.com/crayxt/90aabcaab2c725982624

Hope this helps,

[loveshack]

Baurzhan Muftakhidinov notifications@github.com writes:

@loveshack Scientific Linux has a rebuilt devtoolset for 5th version too. The link is http://linuxsoft.cern.ch/cern/devtoolset/slc5X/x86_64/yum/devtoolset

Thanks for the info, rather late.