[Bug web/60933] New: Please do not advertise outdated version of gmp, mpfr, mpc

["andreas.enge at inria dot fr" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60933

            Bug ID: 60933
           Summary: Please do not advertise outdated version of gmp, mpfr,
                    mpc
           Product: gcc
           Version: 4.9.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: web
          Assignee: unassigned at gcc dot gnu.org
          Reporter: andreas.enge at inria dot fr

This problem does not only concern the web, but "documentation" of
prerequisites in a broader sense.

On the mailing lists of gmp, mpfr and mpc we regularly receive reports with
installation errors concerning very old and no longer maintained versions of
our software, which creates quite some noise. For instance,
   https://gmplib.org/~tege/stats/usage_201404.html#TOPURLS
shows that gmp-4.3.2 is the most downloaded version, while gmp-5.0.0 came out
in early 2010, and gmp-6.0.0 this year. Mpc-1.0.0 came out in fall 2012, and
the 0.8 and 0.9 branches are no longer maintained.

I believe the culprit is gcc too actively promoting the minimally required
versions of the libraries. It is fine if gcc still compiles with older
versions, but all communication should point to the most recent releases.

For instance, trying to install gcc-4.9.0 without gmp results in the following:
configure: error: Building GCC requires GMP 4.2+, MPFR 2.4.0+ and MPC 0.8.0+.
Try the --with-gmp, --with-mpfr and/or --with-mpc options to specify
their locations.  Source code for these libraries can be found at
their respective hosting sites as well as at
ftp://gcc.gnu.org/pub/gcc/infrastructure/.  See also
http://gcc.gnu.org/install/prerequisites.html for additional info.  If
you obtained GMP, MPFR and/or MPC from a vendor distribution package,
make sure that you have installed both the libraries and the header
files.  They may be located in separate packages.

(As an aside, the minimal version numbers seem to be wrong here.) Your ftp
server mentioned in the message provides the outdated libraries corresponding
to the minimal versions with which gmp compiles (and not even the latest bug
fix release in a given release series). If you provide our libraries on your
server, please make sure to always copy the most up-to-date release. Or if this
is too much work, you may prefer to link to ftp.gnu.org/gnu/{gmp,mpfr,mpc}.

On the web at:
   http://gcc.gnu.org/install/prerequisites.html
the text
   GNU Multiple Precision Library (GMP) version 4.3.2 (or later)
could be changed to something like:
   GNU Multiple Precision Library (GMP), preferably the latest version,
   but at least 4.3.2.

I did not make an exhaustive search of the gcc documentation, but there may be
other places where you could point to the most recent gmp, mpfr and mpc
releases to ease our work and to make sure people use up-to-date software in
conjunction with gcc.

Your collaboration is very much appreciated.

Andreas