On Sat, Jul 30, 2016 at 11:51:14AM -0700, Paul Rogers wrote: > Just happened on another box, not sure if it's a problem for discussion > here or upstream. So, I rebuilt my LFS-7.7 system on my i7 box using > one of my 32-bit LFS' (7.2 IIRC). So I expected it to be an i686 > compatible. AAMOF, I'm running it right now on one of my Conroe twin > boxen. It seems to work fine. I have customized the kernel here, no > glitches in gcc. > > [11:26 ~]$ gcc -v > Using built-in specs. > COLLECT_GCC=gcc > COLLECT_LTO_WRAPPER=/usr/libexec/gcc/i686-pc-linux-gnu/4.9.2/lto-wrapper > Target: i686-pc-linux-gnu > Configured with: ../gcc-4.9.2/configure --prefix=/usr > --enable-languages=c,c++ --disable-multilib --disable-bootstrap > --with-system-zlib > Thread model: posix > gcc version 4.9.2 (GCC) > [11:26 ~]$ > > But just to make sure it's i686 as advertized, I've installed it on a > real i686 "Tualatin". My default kernel for installations is > standalone, no NIC support. I expect to customize the kernel real soon. > > So this morning from this box, with the Tualatin box up in a different > room, using its LFS-7,2 based system, I ssh'ed to it, mounted the new > LFS-7.7 partition, chrooted into it and began to recompile the kernel. > Ironically enough it popped an "Invalid Instruction" in bugs.o! It's an > instruction a Conroe can handle. >
Paul, without any more details, that isn't much to go on (you seem to know the instruction, but you didn't share it with the list. I don't think I've used a pIII in this decade, so I don't have a lot to suggest. Also, you haven't mentioned which kernel version - 7.7 had 3.19 which is long out of support upstream. Sometimes, different .config choices cause odd errors, and with luck those get corrected in later stable kernels. > I remember one of the gcc prereqs needed to be specifically told not to > build code for the i7, even if the toolchain is i686. I'm thinking > maybe something (else) did it anyhow. So far, only gmp has been implicated in those sort of problems. Of course, if it _is_ adding instructions which the current CPU cannot execute, you can't recompile it in that system. To be honest, even using any gcc-4.9 version on a pIII was not particularly common - I believe that debian distros used 4.9.3 for a while. Whether 4.9.3 had relevant fixes I don't know. > > I don't expect many of you are still trying out code on i686's. Just > because they're old doesn't mean, to me, that I shouldn't try to get > newer systems on them. But starting over isn't going to help unless I > can figure out where to (try to) enforce the i686 instruction set. > > Any ideas? TIA, as always. > For old hardware, a recent memtest86 variant might show if your DRAM has gone bad. Yes, I realise that if the box runs headless it will be a pain to test that. If it was me, and depending how desperate I was, I might be tempted to build 'kgcc', i.e. a separate version of gcc and matched binutils based on the instructions for LFS pass1 binutils and pass1 gcc, but with both installed into a new directory - and then put that directory first on $PATH both for yourself and for root when making modules_install. For kgcc, at the moment I would use the last gcc-5 (LFS-7.9) withthe corresponding binutils, and a currently-supported stable kernel (the latest 4.1 seems to have netfilter problems, but 4.4.latest with gcc-5 seems to be reliable). But if I was a gambling man I would suspect gmp. ĸen > -- > http://www.fastmail.com - A no graphics, no pop-ups email service > > -- > 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 -- `I shall take my mountains', said Lu-Tze. `The climate will be good for them.' -- Small Gods -- 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
