Hi, The minimum support library version of MPC for building GCC 10 is not correct.
After downloading gcc-10-20191229.tar.xz and $ cd gcc-10-20191229/gcc/doc $ ./install.texi2html $ xdg-open HTML/prerequisites.html I installed - gmp 4.3.2 - works, - mpfr 3.1.0 - works, - mpc 0.8.1 - fails! The failure has been reported already in [1]. The fix is to use - mpc 1.0.3 - works. This wastes some time for everyone who attempts to install GCC 10 from scratch. In [2] it was suggested to look in the contrib/download_prerequisites script. This script indeed contains mpc='mpc-1.0.3.tar.gz' Additionally, the mpc-0.8.1 release is so old that it is not (or no longer) on ftp.gnu.org [3]. Therefore I would suggest 1) to change the documentation (HTML/prerequisites.html) in the GCC 10 snapshots to mention mpc-1.0.3 instead of mpc-0.8.1, 2) likewise, change https://gcc.gnu.org/install/prerequisites.html to mention mpc-1.0.3 instead of mpc-0.8.1. Bruno [1] https://gcc.gnu.org/ml/gcc/2017-05/msg00022.html [2] https://gcc.gnu.org/ml/gcc/2017-05/msg00024.html [3] https://ftp.gnu.org/gnu/mpc/