On Thu, May 28, 2020 at 03:28:17AM +0100, Ken Moffat wrote: > On Thu, May 28, 2020 at 02:08:08AM +0100, Ken Moffat wrote: > > On Wed, May 27, 2020 at 10:13:12PM +0100, Ken Moffat wrote: > > > On Wed, May 27, 2020 at 12:43:26PM +0800, Xi Ruoyao wrote: > > > > > > > > > > When the -O0 override in glibc errored, I changed that to -O1 (still > > > with -march=native). Tests on bash still showed the SIGFPE falure, > > > but I suspect I need to boot the system to properly test it. > > > Unfortunately it locked up overnight (fairly common on that box) so > > > I have not yet got to that stage. > > > > > > Just to be clear, at the moment I'm only trying to detune glibc. > > > > > > > Result! In chroot bash still had the SIGFPE failures, and check had > > the two check_check and check_check_exports failures which prompted > > all of this. > > > > Too much editing and revision before sending, failed to read it - > > > Booted. System is trunk, built from an April build. FLAGS of -O3 > > and -march=native, with hardening where appropriate (not glibc!), > > but for glibc I reduced the FLAGS to -O1 -march=native. > > > > *Host* system was from an April build, the new system is trunk. > > > Built check and ran the tests, all passed. > > > > This is on my ryzen 1300X and it's clear that having a "weird or > > defective" glibc underneath chroot makes running these tests there > > not useful > > > > I'm not at all convinced that I want to continue with -O1 in glibc. > > I'll throw this one away and start another build using glibc's > > default flags (-O2 -g without -march=native). > > > > To be continued, I hope ;-) Meanwhile, thanks to everyone for the > > help and suggestions. > > Building glibc with '-O2 -g' the check tests succeeded after I booted. Will keep this system for a few days (I need a 4 core gcc-10 machine for firefox-68.9.0), then I'll see if adding -march=native affects things : hopefully, I'll use this system as the host, so that I can run the tests in chroot.
But still no closer to working out why this was breaking in 2018 when we first added 'check'. I had an old comment that I forced -O3 in glibc on x86_64 (I think I based it on an old suggestion from Greg Schafer, but google can't find anything relevant), but the added flags had dropped back to only -pipe several years ago. And then at times -march=native appeared in my glibc build. And I suppose I must remember to update my last year's notes on 'tuning' when I understand exactly what caused my raising of sigfpe to break. <sigh/> ĸen -- Do you not know that, what you belittle by the name tree is but the mere four-dimensional analogue of a whole multidimensional universe which - no, I can see you do not. -- Druellae (a Dryad) -- http://lists.linuxfromscratch.org/listinfo/lfs-support FAQ: http://www.linuxfromscratch.org/blfs/faq.html Unsubscribe: See the above information page Do not top post on this list. A: Because it messes up the order in which people normally read text. Q: Why is top-posting such a bad thing? A: Top-posting. Q: What is the most annoying thing in e-mail? http://en.wikipedia.org/wiki/Posting_style
