> On Feb 6, 2018, at 5:26 PM, Bas Vermeulen <b...@daedalean.ai> wrote: > > I am evaluating the following patch to gcc-7 to fix the problem. It's > currently building, I'll follow up when I know it works. The patch is added > to debian/rules.patch to get it included.
Why do you want to patch the upstream sources when you could just modify debian/rules2 to pass the proper “—with-cpu=powerpc64” to gcc’s configure script? Adrian > Bas Vermeulen > >> On Tue, Feb 6, 2018 at 5:16 PM, Lennart Sorensen >> <lsore...@csclub.uwaterloo.ca> wrote: >> On Tue, Feb 06, 2018 at 03:40:20PM +0100, Bas Vermeulen wrote: >> > I am trying to run the ppc64 unstable on a Freescale T2080, which uses the >> > e6500 CPU. Running python (or any other application using sqrt or sqrtf) >> > will cause an illegal instruction exception, because the sqrtf opcode is >> > not supported on the e6500. >> > >> > This seems to be caused by gcc compiling for power4 by default >> > (_ARCH_PWR4=1 and _ARCH_PPCSQ=1 set in gcc -E -mD - < /dev/null), although >> > jrtc27 on #debian-ports pointed to >> > https://github.com/gcc-mirror/gcc/blob/da8dff89fa9398f04b107e388cb706517ced9505/gcc/config/rs6000/default64.h#L30 >> > which sets MASK_PPC_GPOPT by default (which includes fp sqrt). >> > >> > What would be the best way to solve this problem? >> >> Why is the default not powerpc64 instead of power4? After all that is >> the setting for generic 64 bit bit endian powerpc as far as I know. >> >> It seems the e6500 is missing quite a few floating point instructions >> from the Power ISA so targeting power4 (which is I believe full Power >> ISA 2.01) is likely to cause issues. >> >> -- >> Len Sorensen > > <ppc64-use-powerpc64-by-default.diff>
