On 2012-06-08, William Stein <wst...@gmail.com> wrote: > On Fri, Jun 8, 2012 at 10:58 AM, Justin C. Walker <jus...@mac.com> wrote: >> >> On Jun 7, 2012, at 16:19 , William Stein wrote: >> >>> Hi Sage-Devel, >>> >>> I'm randomly running into segfaults when multiplying matrices over the >>> integers, in the course of doing basic modular symbols calculations. >>> For example, sometimes (but not always), this crashes: >>> >>> sage: M = ModularSymbols(389,sign=0).cuspidal_submodule().decomposition()[0] >> >> I used the "for loop" from earlier in the thread on Mac OS X (both 10.6.8 >> and 10.7.4). >> In both cases, all worked w/o crashing. >> >> Does this happen rarely, sometimes, frequently? > > It occurred for me about 4 times interactively while working on > research yesterday. Anyway, thanks for any info.. > was it on OSX 10.7? Apple has changed the BLAS/LAPACK they ship for 10.7, in particular some undefined behaviour is now different from what it was. We had learned this hard way, with CVXOPT upgrade. See #12011. Could it be a similar issue?
Just in case, Dima >> >> Justin >> >> -- >> Justin C. Walker, Curmudgeon-At-Large, Director >> Institute for the Enhancement of the Director's Income >> -------- >> The path of least resistance: >> it's not just for electricity any more. >> -------- >> >> >> >> -- >> To post to this group, send an email to sage-devel@googlegroups.com >> To unsubscribe from this group, send an email to >> sage-devel+unsubscr...@googlegroups.com >> For more options, visit this group at >> http://groups.google.com/group/sage-devel >> URL: http://www.sagemath.org > > > > -- > William Stein > Professor of Mathematics > University of Washington > http://wstein.org > -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
