https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94868
--- Comment #2 from Zhao Jing <zhaojing2 at longcheer dot com> --- Dear Richard Biener: I have already installed gmp/mpfr/mpc before install gcc. zhaojing2@ubuntu:/opt/gcc-4.6.3$ ls gmp-4.3.2/gmp_install/ include lib share zhaojing2@ubuntu:/opt/gcc-4.6.3$ ls mpfr-2.4.2/mpfr_install/ include lib share zhaojing2@ubuntu:/opt/gcc-4.6.3$ ls mpc-0.8.1/mpc_install/ include lib share I suggest you try building gmp/mpfr/mpc in-tree by invoking ./contrib/download_prerequesites prior to build rather than using (possibly bogus) libs in /opt. ==> What's the next step atfer invoking ./contrib/download_prerequesites? Could you please describe more details? How can I install the gcc step by step? How should I make the configure? Thanks.