On Monday, 23 April 2018 11:57:12 BST Walter Dnes wrote: > > I think I've found the problem. It's in the -march setting, which of > > course has to be specific in the chroot, not "native." I had it set > > to "silvermont," but now I can't see why I did that. The target CPU > > is a celeron N3150, which according to an Intel site is "Products > > formerly Braswell" [1]. None of the Gentoo or GCC optimisation sites > > I could find even mention braswell, silvermont or model 76. > > > > So I changed make.conf to braswell, and now I get "error: bad > > value (braswell) for -march= switch" from the compiler during any > > emerge. > > Sounds like an invalid value. To find out what gcc thinks the machine > really is, *ON THE CELERON*, execute the command... > > gcc -c -Q -march=native --help=target | grep march=
Ah, that was it. My searching didn't turn that one up - thanks. $ gcc -c -Q -march=native --help=target | grep march= -march= silvermont > On my ancient core2, I get... > > -march= core2 > > Use whatever value the above query returns on the Celeron. Silvermont > is a recent 64 bit Atom. For a big list of gcc-7.3 supported cpus, see > https://gcc.gnu.org/onlinedocs/gcc-7.3.0/gcc/x86-Options.html#x86-Options -- Regards, Peter.
