On Wed, 3 May 2017, Joel Sherrill wrote: > My conclusion is that INSTALL/prerequisites.html is wrong on two > of the support libraries. Someone more knowledgeable will have > to narrow down the real minimum. I am just reporting what builds.
The listed minima are for the scenario that you have a very old OS, or built the libraries some years ago, and want to know whether you need to update your OS or build new libraries. If you are building the libraries at the same time as GCC, there is no reason to use old versions, and you should use current ones (and the download_prerequisites script should be updated whenever new versions are released upstream, at least when GCC's not in a release freeze). The manual explicitly states "The in-tree build is only supported with the GMP version that download_prerequisites installs.", and likewise for MPFR and MPC. -- Joseph S. Myers jos...@codesourcery.com