On 04/28/2015 11:35 AM, Orion Poplawski wrote: > Re: https://bugzilla.redhat.com/show_bug.cgi?id=1127544 > > It appears that shared libraries compiled with -ffast-math (as libopenjpeg.so > is) will call set_fast_math() in the library init code: > > Watchpoint 1: $mxcsr > > Old value = [ IM DM ZM OM UM PM ] > New value = [ DAZ IM DM ZM OM UM PM FZ ] > 0x00007fffe619d112 in set_fast_math () from /lib64/libopenjpeg.so.1 > (gdb) bt > #0 0x00007fffe619d112 in set_fast_math () from /lib64/libopenjpeg.so.1 > #1 0x00007ffff7deaf2a in call_init (l=<optimized out>, argc=argc@entry=1, > argv=argv@entry=0x7fffffffd6a8, env=env@entry=0x7fffffffd6b8) at dl-init.c:76 > > This will then affect the floating point operations of all code run after the > library is loaded, regardless of its use of -ffast-math or not, which can lead > to some unexpected behavior. > > This seems like it's a pretty broad and generic problem and I'm wondering how > best to handle it. > So, the solution appears to be that libopenjpeg (and any other library) should not link with -ffast-math, but only compile with it. https://bugzilla.redhat.com/show_bug.cgi?id=881489 This appears to be the gcc bug mentioned in that report: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=55522 -- Orion Poplawski Technical Manager 303-415-9701 x222 NWRA, Boulder/CoRA Office FAX: 303-415-9702 3380 Mitchell Lane orion@xxxxxxxx Boulder, CO 80301 http://www.nwra.com -- devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxxx https://admin.fedoraproject.org/mailman/listinfo/devel Fedora Code of Conduct: http://fedoraproject.org/code-of-conduct
