Hi Honza, So we have some proof-of-concept LTO work pushed to the LibreOffice repository - care to have a look & try it how it copes with your changes in gcc etc.? ;-)
git clone git://anongit.freedesktop.org/libreoffice/core sudo zypper si -d libreoffice-bootstrap ./autogen.sh --enable-lto make make dev-install More here: http://www.libreoffice.org/get-involved/developers/ , or appear on #libreoffice-dev on irc.freenode.net :-) All the best, Kendy On 2011-08-20 at 23:04 +0200, Matúš Kukan wrote: > Hello, > > I created patch, which allows link-time optimization (--enable-lto) > for shared libraries, you need at least gcc-4.5 (I'm not checking for > version in configure). > gcc-4.5 is not really good for lto but I was able to install > LibreOffice with lto enabled. I don't know what should I try to test > if it is really faster and how much. > Building is slower because gcc is compiling sources twice ? or > something like that. But real problem is that lto is memory expensive. > We could gain more with bigger libraries but it's not possible with > gcc-4.5, I'm afraid. > Unfortunately I was not able to install gcc-4.6, so I don't know if > it's better but it should. > > You can use gold as linker for elf libraries, it's really faster but > linking phase it's not that much. > Most of the time is running lto1 executable and it eat cca 2GB RAM > when optimizing sw library. (cca 4,5 minutes for me) > > So it is possible but not in parallel. And not for really big libraries. > I am hoping it will be much better with gcc-4.6. > > ok to push ? For sure there could be better message at least in configure. > > Best regards, > > Matúš > _______________________________________________ > LibreOffice mailing list > LibreOffice@lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/libreoffice _______________________________________________ LibreOffice mailing list LibreOffice@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/libreoffice
