Hi Fokko,
On 25/09/15 13:23, Fokko Masselink wrote:
Hi Kenneth,
thank you for the explanation.
It answers my question, though it seems it won't help me to get what I'm
after.
By default I want to create a "generic" build: so optarch=False.
Setting --optarch to an empty string should have this effect.
While I build (currently only on a SandyBridge), though I have some older
systems as well and the newer systems dont always need hw optimized code for
quite some applications.
Only for specific software I want to build optimized versions. So when I use a
Haswell to build I want to still build generic, but once in a while I want to
have an optimized version for it.
But when optarch=False, --optarch on the commandline has no effect.
To me it would be handy if --optarch= on the commandline would trigger a
optarch:True and set it to what I provide on the commandline.
This makes sense I think: defining --optarch implies enabling the use of
the architecture-specific flags.
However, having the 'optarch' toolchain option set to True is the
default anyway, and for easyconfigs that define `optarch: False`,
there's usually a good reason.
So, maybe you just want to use --optarch='' instead, rather than
changing "optarch: False" in easyconfigs everywhere?
I would somehow like to see a way to achieve the above.
Only thing I could think of (with the current version of EB):
change optarch to True (or unset, while it is the default)
and override my default builds with "--optarch=O2"
Can I leave optarch empty, so it behaves like optarch: False?
Yes, --optarch='' implies not using any architecture-specific flags
(regardless of whether the 'optarch' toolchain option is set to False or
True).
Can you add multiple values to optarch, like:
--optarch="xSSE4.2 axAVX,CORE-AVX-I,CORE-AVX2"
or should it be:
--optarch="xSSE4.2 -axAVX,CORE-AVX-I,CORE-AVX2"
The latter, but I consider requiring the first `-` to be stripped out a
bug that we should fix.
You should be able to use --optarch="-xSSE4.2 -axAVX...", but now
that'll lead to using --xSSE4.2 -axAVX...
regards,
Kenneth
