Le 15/11/2014 13:43, Fernando a écrit : > Hi Pierre, > > > I installed gcc-4.9.2 when the ticket was still open. Today, after some > problems with kdepin-4.14.3, comparing my instructions, I saw that > switch, in my script: > > > --disable-bootstrap \ > > Should it make such a difference that I should reinstall it without that > switch? > > > I also use > > --enable-languages=c,c++,fortran,go,objc,obj-c++ > > but don't think this is a problem. >
Well, all I can tell you is already in the book ;-): "The instructions below are intentionally performing a “bootstrap” process. Bootstrapping is needed for robustness and is highly recommended when upgrading the compilers version. To disable bootstrap anyways, add --disable-bootstrap to the ./configure options below." The problem with compilers is that they have to compile themselves (bootstrap). If you disable bootstrap, you compile gcc-4.9.2 with gcc-4.9.1 (or any previous version), and stop there. Bootstrapping allows to first build gcc-<new-version> with gcc-<old-version>, then immediately recompile gcc-<new-version> with the just built gcc-<new-version>. In a perfect world, that should be enough, but the GCC devs have added a third stage, where they again recompile gcc-<new-version> with the compiler obtained at stage 2. They then compare the third stage compiler with the second stage compiler, and fail if there is too much difference. Then, the libraries and other compilers (obj-c, fortran,...) are compiled with the C/C++ compilers obtained at stage 3. Of course, the first stage could be enough, but I am almost sure upstream always test with bootstrapping, so they'll never warrant that stage 1 is enough. So, if you are not in a hurry, always "use bootstrap, Luke"... Sincerely, Pierre -- http://lists.linuxfromscratch.org/listinfo/blfs-support FAQ: http://www.linuxfromscratch.org/blfs/faq.html Unsubscribe: See the above information page
