Re: configure for gcc 6.4.0 build on Fedora 27

["U.Mutlu" <um at mutluit dot com>]

And after the make, do this:

Make this new compiler the default for this user
by appending these lines to this user's ~/.bashrc :
  export PATH=/usr/local/gcc-latest/bin:$PATH
  export LD_LIBRARY_PATH=/usr/local/gcc-latest/lib64:$LD_LIBRARY_PATH

Then start a fresh bash shell (or logout from bash and re-login),
so that the above settings will take effect.
You can verify with "echo $PATH" --> the new ccompiler's dir
should come as first.
...and try the new compilers "g++-latest", "gcc-latest",
or whatever names you chose for them.


U.Mutlu wrote on 06/14/2018 09:51 AM:
> Hi,
> FYI: this is my configure command:
>
> ../gcc_trunk/configure -v \
> --build=x86_64-linux-gnu \
> --host=x86_64-linux-gnu \
> --target=x86_64-linux-gnu \
> --disable-multilib \
> --enable-checking=release \
> --enable-languages=c,c++ \
> --enable-lto \
> --prefix=/usr/local/gcc-latest \
> --program-suffix=-latest
>
> This way the compilers will be named "gcc-latest" and "g++-latest"
> You can change this to your 6.4.0 version.
>
>
>
> U.Mutlu wrote on 06/14/2018 09:41 AM:
> > stimits@comcast.net wrote on 06/14/2018 08:53 AM:
> > > Hi,
> > >
> > > I downloaded the subversion tag for gcc 6.4.0. Within this I used the
> > > "contrib/download_prerequisites" script, and thus there now exists
> > > subdirectories to the gcc source of:
> > >   mpfr-2.4.2
> > > gmp-4.3.2
> > > mpc-0.8.1
> > > isl-0.15
> > >
> > > I also built and installed these in "/usr/local/mpfr-2.4.2/",
> > > "/usr/local/gmp-4.3.2/", "/usr/local/mpc-0.8.1/", and "/usr/local/isl-0.15/".
> > >
> > > If I use "./configure" for gcc in any way it fails claiming incorrect
> > > versions shortly after declaring they are correct. For example, directly
> > > from the download_prerequisites content:
> > > ./configure --prefix=/usr/local/gcc_6-4-0
> > > --with-mpfr=/usr/local/src/gcc-x86_64/gcc_6_4_0/mpfr-2.4.2/
> > > --with-gmp=/usr/local/src/gcc-x86_64/gcc_6_4_0/gmp-4.3.2
> > > --with-mpc=/usr/local/src/gcc-x86_64/gcc_6_4_0/mpc-0.8.1
> > > --with-isl=/usr/local/src/gcc-x86_64/gcc_6_4_0/isl-0.15
> > >
> > > It also fails if I configure for the "/usr/local/" installs:
> > > ./gcc_6_4_0/configure --prefix=/usr/local/gcc_6-4-0
> > > --with-mpfr=/usr/local/mpfr-2.4.2/ --with-gmp=/usr/local/gmp-4.3.2
> > > --with-mpc=/usr/local/mpc-0.8.1 --with-isl=/usr/local/isl-0.15
> > >
> > > In all cases the log shows the header files were correct, and that the
> > > libraries exist, but that for some reason (I suspect a bug) the versions are
> > > not accepted:
> > > checking for the correct version of gmp.h... yeschecking for the correct
> > > version of mpfr.h... yeschecking for the correct version of mpc.h...
> > > yeschecking for the correct version of the gmp/mpfr/mpc libraries...
> > > noconfigure: 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
> > > specifytheir locations.  Source code for these libraries can be found at
> > > I have tried with the separate objdir as well as in the source tree. Is
> > > there a bug preventing the correct versions from being detected? Is there
> > > something missing in the documentation needed as a workaround when using the
> > > "download_prerequisites" script?
> > >
> > > Thanks!
> >
> > Just leave the downloaded directories in the repository directory.
> > Then, from a new directory outside the repository start the configure...
> > Ie. something like ../my_repo/configure ...