Hi folks,

I'm trying to build the experimental version gcc-6.0-20151101 
on a x86_64 machine (i7-3930K, 3.20GHz) with Fedora 22, i.e.:

Linux version 4.2.3-200.fc22.x86_64 
(mockbuild@bkernel01.phx2.fedoraproject.org) 
(gcc version 5.1.1 20150618 (Red Hat 5.1.1-4) 
(LE)) # 1 SMP Thu 8 October 03: 2015 23:55 UTC.

but, at the make phase, fails with the error message:

gcc.o gcc-main.o ggc-none.o cp/g++spec.o driver-i386.o  \ 
  libcommon-target.a libcommon.a ../libcpp/libcpp.a \
  ../libbacktrace/.libs/libbacktrace.a \
  ../libiberty/libiberty.a ../libdecnumber/libdecnumber.a 
g++: fatal error: unknown spec function 'gt'
compilation terminated.
../../gcc/cp/Make-lang.in:59: recipe for target 'xg++' failed
make[3]: *** [xg++] Error 1
make[3]: Leaving directory '/home/bigpack/gcc-paq/sources/gcc-6.0-20151101/BUILD/gcc'
Makefile:4384: recipe for target 'all-stage1-gcc' failed
make[2]: *** [all-stage1-gcc] Error 2
make[2]: Leaving directory '/home/bigpack/gcc-paq/sources/gcc-6.0-20151101/BUILD'
Makefile:25626: recipe for target 'stage1-bubble' failed
make[1]: *** [stage1-bubble] Error 2
make[1]: Leaving directory '/home/bigpack/gcc-paq/sources/gcc-6.0-20151101/BUILD'
Makefile:916: recipe for target 'all' failed
make: *** [all] Error 2

With regards to binutils, glibc, etc., I used 

dnf groupinstall 'C Development Tools and Libraries'
dnf groupinstall 'development-tools'
dnf install gcc* 
dnf install binutils* glibc* 
dnf install mpfr* libmpc* gmp*
dnf install isl* cloog* compat-gcc*
dnf install libtool* libstdc++*
dnf install kernel* texinfo* llvm*
dnf distro-sync

among others packages. With regard to GMP, MPFR and MPC packages, 
I tried both those provided by the OS, as those obtained through 
./contrib/download_prerequisites. I've also tried to make minimal 
installations (e.g. only the C language, without multilib, etc.), 
but always with the same error message. See attached file with 
some logs. Please, any clue to solve it? 

BTW, on the other side, are there broken links in the phrase:
"Download from gfortran.com (README, nightly builds, 4.3 to 4.9 snapshots)" 
in https://gcc.gnu.org/wiki/GFortranBinaries 
?

Thanks in advance. 
Jorge.
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