On Sat, Jan 09, 2016 at 02:57:07PM -0600, Bruce Dubbs wrote: > DJ Lucas wrote: > >Binutils Gold: It was decided a long time ago not to build gold. I > >brought it up on list when it was new (binutils-2.19), but I searched > >and don't think it's been discussed much since then. It has grown up a > >bit since that time. My only argument for this is that people might want > >it, and we can provide it without affecting our build much (time and > >disk space). As far as BLFS is concerned, the only real beneficiary that > >I can think of might be QT. I'm sure there are a couple of others, but > >that is the biggest C++ project that I'll use (besides chromium which > >isn't in the book). There are plenty of other places it could be used, > >but for now, just having available is enough. > > > >There are two caveats, we do have to patch it because of lack of back > >ports in the release tree (patch is in our repo), and the testsuite has > >some issues (10 failures). I work around the test suite by removing from > >main suite and just running it separately and catching the error (as I > >build with set -e). Fixing to do a jhalfs run so that I can get more > >accurate timings and build sizes as compared with my packaged build. I > >had a 4 minute difference (10 vs 6), 3 of which was the test suite. Any > >interest in doing this for LFS? We'd still install bfd as the default > >linker as we do now, just add ld.gold (and dwp) to the list of installed > >files. > > The size and time are not really a factor. The question is what does it > provide? If the primary target audience is developers, then I don't think > it's needed in the book. A hint might be appropriate though. > (limiting my comments to gold) -
When I last looked at this, I think I got put off by too many problem reports. Certainly, at one time there were problems with the kernel : perhaps those have been fixed by now. Gentoo still advise proceding with caution if making gold the default, because gold _was_ known to break grub2, making the system unbootable [ https://wiki.gentoo.org/wiki/Gold ]. OTOH, 'buntu-derived distros seem to have been using it for years (not sure if they set it as the default - if so, Mint is presumably using it). Gold is intended to provide faster linking - I guess that firefox might benefit from that. This looks like something which will only ever be used for "mainstream" architectures - not a problem for us, but the sort of thing which will prevent distros that cover multiple architectures from using it. Summary, and how to use it, at [ https://en.wikipedia.org/wiki/Gold_%28linker%29 ]. If we use it, there seems to be a possibility that something in BLFS might not work (probably, might not link - the grub2 problem sounds like the sort of weirdness to which bootloaders are prone. Oddly, googling for 'problems with ld.gold' got links to learning disability articles, as well as stuff about the shiny metal. Of *recent* issues, I found: · a requirement for gold by some aarch64 package in fedora: fixed in F23 Rawhide, although there was a subsequent bug report from that re broken AC_CHECK_SIZEOF(long long, 8) : presumably that works ok on x86{,_64} · a gentoo fix for libgdiplus (seems to be part of mono) - that looks like it needed to add -lm It also looks as if LLVM can use it, with a plugin, if anybody cares about that. Overall, it seems like an interesting thing to try - at the moment I have zero time for this. It would also be interesting, in the interests of research, to build big C++ packages (DESTDIR style) and compare the change in overall time. Using -j4 or whatever should be fine for that. If it really does help, I suppose that libreoffice would also be worth testing. Ah - looking at that llvm page I found [ http://llvm.org/docs/GoldPlugin.html ] it seems you can check the default linker using 'ld -v' with expected results of 'GNU gold' if it is the default, or 'GNU ld' for the rest of us. I suspect trying that will show that most distros are NOT using it be default, but evidence would be nice. ĸen -- This email was written using 100% recycled letters. -- http://lists.linuxfromscratch.org/listinfo/lfs-dev FAQ: http://www.linuxfromscratch.org/faq/ Unsubscribe: See the above information page
