Hi Neels,

On Sat, Aug 12, 2017 at 04:36:48AM +0200, Neels Hofmeyr wrote:

> a) debian packages should be usable on the largest set of CPUs, we should not
> build with CPU instructions we can't guarantee to be supported. So I guess we
> need a --without-sse configure option in libosmocore. Makes sense?

No, sorry.  We are *compiling* code for various CPU instruction sets, and 
at runtime, just like ffpmeg and many other projects with (optional) 

> b) I'm puzzled that the same host that built conv_gsm0503_test fails to run 
> it.
> Is our SSE check in libosmocore's configure.ac broken? How to verify?

I'm not sure why you imply the assumption that the compiler capability to 
instructions for a certain CPU feature set should be related to the actual
capability of the CPU to execute them.

You can always generate code that you cannot execute, this is quite normal.

> c) would be nice to find out what kind of host cumulus3 is; so far we know 
> only
> that it is an x86_64. https://build.opensuse.org/monitor

Can we somehow "cat /proc/cpuinfo" during the build and get the output of that? 
could put this in the packaging rules or even in the makefile?  Or even compile 
into the binary with something like "-DCOMPILEHOST_CPUFLAGS=`cat /proc/cpuinfo`"

I've right now tested to build + make check libosmocore.git master
on a very old x86_64 machine, one of the first processors ever to support the
instructions set.  Worked fine:

=== AMD Opteron 250
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov 
pat pse36 clflush mmx fxsr sse sse2 syscall nx mmxext lm 3dnowext 3dnow 
rep_good nopl extd_apicid

It could of course be that the packaging rules or the environment of OBS do
something odd to the compiler optimization flags that would make an
obs-built-binary behave different from a manually built one...

- Harald Welte <lafo...@gnumonks.org>           http://laforge.gnumonks.org/
"Privacy in residential applications is a desirable marketing option."
                                                  (ETSI EN 300 175-7 Ch. A6)

Reply via email to