----- Original Message ----- From: "Ken Moffat" <[email protected]> To: <[email protected]> Sent: Sunday, May 09, 2010 6:37 PM Subject: gmp note (#2648)
> Moving this here from trac. When I put the ABI=32 note in, I > screwed up. But it's only 2 weeks ago that anyone noticed. > > In the meantime, building for x86_64 is now supported by LFS, so > the current note could also be misinterpreted. > > There is a second issue on the ticket - if I've understood correctly, > this only happens when you build on one machine to run on a > different (probably, "lesser") machine. If that is correct, I think > it's worth noting even though we don't necessarily support this. > > I've taken a first stab at rewording and expanding the note, > but I'd appreciate some review. The page is at > http://www.linuxfromscratch.org/~ken/tmp/chapter06/gmp.html > (only that page, plus images and stylesheets so that it renders). > > ĸen > -- Just tested on AMD Athlon(tm) 64 Processor 3500+, 32bits distrib, with only ./configure --build=i486-linux this result in ... checking for egrep... /bin/grep -E using ABI="32" CC="gcc -std=gnu99" CFLAGS="-m32 -O2 -pedantic -fomit-frame-pointer -mtune=i486 -march=i486" CPPFLAGS="" MPN_PATH=" x86/i486 x86 generic" So adding ABI=32 is not strictly needed when the build cpu is 32 bits only. That's hard to search for host_cpu on configure script as 90 lines match that word. I would advice to search near i486*. For the first part of the explanation, there is different way to force 32bits compilation (linux32, CFLAGS). ABI=32 could be indicated before or after configure. I would write : On 64-bits capable CPU using a 32-bits distrib, you need to add ABI=32 on the ./configure line or select a 32-bits CPU using --build=[CPU]-linux. If you want to be able to run the compiled code on a less capable CPU than the building machine. Use for example --build=i486-linux allow to run on any i486 or more capable machine. Search near i486* on configure script for the list of available CPU options. Gilles -- http://linuxfromscratch.org/mailman/listinfo/lfs-dev FAQ: http://www.linuxfromscratch.org/faq/ Unsubscribe: See the above information page
