There's also a 3rd bug which is in fflas-ffpack which assumes that if there's no cblas, then it's not openblas. This can be fixed by copying the lines https://github.com/linbox-team/fflas-ffpack/blob/2d3af1a5bec51983b5a896fae12e60914d9bdc4d/fflas-ffpack/config-blas.h#L315-L317 to Line 311 above the #else
Isuru On Wed, Jan 22, 2020 at 9:13 AM Vincent Delecroix <20100.delecr...@gmail.com> wrote: > Le 22/01/2020 à 15:41, Dima Pasechnik a écrit : > > On Wed, Jan 22, 2020 at 2:31 PM Vincent Delecroix > > <20100.delecr...@gmail.com> wrote: > >> > >> I had the same annoying trouble... Is it really a bug in arch? I don't > >> find anywhere where libopenblas is supposed to provide the LAPACK > >> interface. To me it is just true for SageMath and false for Archlinux. > > > > well, a "bug", in the sense that their openblas configuration just > > does not make any sense, > > because if you install a highly optimised BLAS implementation, which can > also > > provided a highly optimised CBLAS and LAPACK, in a sane world you'd > install them > > too. But Arch does not do this, it instead provides dog-slow CBLAS and > > LAPACK, built > > from another (reference, i.e. no assembler, no optimisation) > implementation. > > This causes Sage's logic, which expects that openblas will also > > provide CBLAS and LAPACK, to fail. > > > > Yes, it is possible to make tests to detect this silly setup, but I > > think that everyone's time > > is much better spent if Arch provided a full build of openblas, with > > CBLAS and LAPACK, > > instead. > > Hence there are two bugs > > * a "logical" bug in archlinux that provides a slow lapack for > (apparently) no good reason > > * a structural bug in SageMath that assumes that openblas does > install the LAPACK interface > > I tend to agree that the resolution of any of these two would solve > the compilation. But in an ideal world we would just solve the two. > > >> > >> Le 13/01/2020 à 11:44, Dima Pasechnik a écrit : > >>> On Sat, Jan 11, 2020 at 11:35 AM arojas <nqn1...@gmail.com> wrote: > >>>> > >>>> El sábado, 11 de enero de 2020, 11:23:32 (UTC+1), Dima Pasechnik > escribió: > >>>>> > >>>>> > >>>>> > >>>>> On Sat, 11 Jan 2020, 10:19 arojas, <nqn...@gmail.com> wrote: > >>>>>> > >>>>>> I suspect this may be due to our openblas package only providing > libblas.so (not libcblas.so or liblapack.so, which in our case come from > the netlib blas). > >>>>> > >>>>> > >>>>> Are you saying that your libopenblas.so does not provide everything > that is in openblas by default? > >>>>> > >>>>> This is largely defeating its purpose. > >>>>> Sage's openblas does provide the cblas and lapack capabilities. > >>>> > >>>> > >>>> In that case, openblas' spkg-configure should check whether cblas > symbols are provided by the system openblas, and if not it should compile > sage's one. It shouldn't unconditionally assume that that's always the case. > >>> > >>> I maintain that it's a bug in Arch, that libopenblas cannot be used as > >>> a replacement of cblas and lapack, for it defeats its purpose. > >>> Most uses of BLAS routines are either via LAPACK, or from C/C++, via > cblas. > >>> > >>> > >>> > >>>> > >>>> -- > >>>> You received this message because you are subscribed to the Google > Groups "sage-devel" group. > >>>> To unsubscribe from this group and stop receiving emails from it, > send an email to sage-devel+unsubscr...@googlegroups.com. > >>>> To view this discussion on the web visit > https://groups.google.com/d/msgid/sage-devel/a1516e56-ab25-410e-be0f-75a7a6713466%40googlegroups.com > . > >>> > >> > >> -- > >> You received this message because you are subscribed to the Google > Groups "sage-devel" group. > >> To unsubscribe from this group and stop receiving emails from it, send > an email to sage-devel+unsubscr...@googlegroups.com. > >> To view this discussion on the web visit > https://groups.google.com/d/msgid/sage-devel/dbf38073-170b-4c7d-63b9-d4429a8794e2%40gmail.com > . > > > > -- > You received this message because you are subscribed to the Google Groups > "sage-devel" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to sage-devel+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/sage-devel/e3ad609d-8d21-bb10-2876-367fdf1b7e24%40gmail.com > . > -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/sage-devel/CA%2B01voMdYrJZG2Pa5t56KLAxUcTV2cLtY64snE%2BGwBcALh%3DX-Q%40mail.gmail.com.
