error while building trunk (only for c++) on ubuntu 14.04 LTS

[Prathamesh Kulkarni]

On 21 January 2016 at 01:07, acc2 <meinaccountnr2@web.de> wrote:
> hi.
> i am trying to build gcc 6 (since i want to try out some c++17 features)
> and get an error:
>
> two systems: ubuntu 14.04 LTS
> A: as direct system (svn Revision: 232603)
> B: in virtual box   (svn Revision: 232581)
>
> directories:
> gcc
>  - srcdir (the svn repo)
>  - objdir
>  - installdir
>
> running:
> cd objdir
> ../srcdir/configure --prefix=/home/qwer/gcc/installdir/ --enable-threads
> --enable-link-mutex --enable-languages=c++ --disable-multilib
> make profiledbootstrap
>
> the failing command:
>
> on A (using the contrib/download_prerequisites script):
> /home/SMBAD/grimm/home/gcc/objdir/./prev-gcc/xg++
> -B/home/SMBAD/grimm/home/gcc/objdir/./prev-gcc/
> -B/home/qwer/gcc/installdir/x86_64-pc-linux-gnu/bin/ -nostdinc++
> -B/home/SMBAD/grimm/home/gcc/objdir/prev-x86_64-pc-linux-gnu/libstdc++-v3/src/.libs
> -B/home/SMBAD/grimm/home/gcc/objdir/prev-x86_64-pc-linux-gnu/libstdc++-v3/libsupc++/.libs
> -I/home/SMBAD/grimm/home/gcc/objdir/prev-x86_64-pc-linux-gnu/libstdc++-v3/include/x86_64-pc-linux-gnu
> -I/home/SMBAD/grimm/home/gcc/objdir/prev-x86_64-pc-linux-gnu/libstdc++-v3/include
> -I/home/SMBAD/grimm/home/gcc/srcdir/libstdc++-v3/libsupc++
> -L/home/SMBAD/grimm/home/gcc/objdir/prev-x86_64-pc-linux-gnu/libstdc++-v3/src/.libs
> -L/home/SMBAD/grimm/home/gcc/objdir/prev-x86_64-pc-linux-gnu/libstdc++-v3/libsupc++/.libs
> -fno-PIE -c   -g -O2 -fprofile-use -DIN_GCC     -fno-exceptions
> -fno-rtti -fasynchronous-unwind-tables -W -Wall -Wno-narrowing
> -Wwrite-strings -Wcast-qual -Wmissing-format-attribute
> -Woverloaded-virtual -pedantic -Wno-long-long -Wno-variadic-macros
> -Wno-overlength-strings -Werror -fno-common  -DHAVE_CONFIG_H -I. -I.
> -I../../srcdir/gcc -I../../srcdir/gcc/. -I../../srcdir/gcc/../include
> -I../../srcdir/gcc/../libcpp/include
> -I/home/SMBAD/grimm/home/gcc/objdir/./gmp
> -I/home/SMBAD/grimm/home/gcc/srcdir/gmp
> -I/home/SMBAD/grimm/home/gcc/objdir/./mpfr
> -I/home/SMBAD/grimm/home/gcc/srcdir/mpfr
> -I/home/SMBAD/grimm/home/gcc/srcdir/mpc/src
> -I../../srcdir/gcc/../libdecnumber
> -I../../srcdir/gcc/../libdecnumber/bid -I../libdecnumber
> -I../../srcdir/gcc/../libbacktrace
> -I/home/SMBAD/grimm/home/gcc/objdir/./isl/include
> -I/home/SMBAD/grimm/home/gcc/srcdir/isl/include  -o omp-low.o -MT
> omp-low.o -MMD -MP -MF ./.deps/omp-low.TPo ../../srcdir/gcc/omp-low.c
>
> on B (using packages from the repo):
> /home/qwer/gcc/objdir/./prev-gcc/xg++
> -B/home/qwer/gcc/objdir/./prev-gcc/
> -B/home/qwer/gcc/installdir/x86_64-pc-linux-gnu/bin/ -nostdinc++
> -B/home/qwer/gcc/objdir/prev-x86_64-pc-linux-gnu/libstdc++-v3/src/.libs
> -B/home/qwer/gcc/objdir/prev-x86_64-pc-linux-gnu/libstdc++-v3/libsupc++/.libs
> -I/home/qwer/gcc/objdir/prev-x86_64-pc-linux-gnu/libstdc++-v3/include/x86_64-pc-linux-gnu
> -I/home/qwer/gcc/objdir/prev-x86_64-pc-linux-gnu/libstdc++-v3/include
> -I/home/qwer/gcc/srcdir/libstdc++-v3/libsupc++
> -L/home/qwer/gcc/objdir/prev-x86_64-pc-linux-gnu/libstdc++-v3/src/.libs
> -L/home/qwer/gcc/objdir/prev-x86_64-pc-linux-gnu/libstdc++-v3/libsupc++/.libs
> -fno-PIE -c   -g -O2 -fprofile-use -DIN_GCC     -fno-exceptions
> -fno-rtti -fasynchronous-unwind-tables -W -Wall -Wno-narrowing
> -Wwrite-strings -Wcast-qual -Wmissing-format-attribute
> -Woverloaded-virtual -pedantic -Wno-long-long -Wno-variadic-macros
> -Wno-overlength-strings -Werror -fno-common  -DHAVE_CONFIG_H -I. -I.
> -I../../srcdir/gcc -I../../srcdir/gcc/. -I../../srcdir/gcc/../include
> -I../../srcdir/gcc/../libcpp/include  -I../../srcdir/gcc/../libdecnumber
> -I../../srcdir/gcc/../libdecnumber/bid -I../libdecnumber
> -I../../srcdir/gcc/../libbacktrace   -o omp-low.o -MT omp-low.o -MMD -MP
> -MF ./.deps/omp-low.TPo ../../srcdir/gcc/omp-low.c
>
> error (same for both modulo home directory):
> ../../srcdir/gcc/omp-low.c: In function ‘void
> expand_omp_target(omp_region*)’:
> ../../srcdir/gcc/omp-low.c:13345:8: error: ‘i_async’ may be used
> uninitialized in this function [-Werror=maybe-uninitialized]
>       args.safe_push (oacc_launch_pack
>                       ~~~~~~~~~~~~~~~~
>         (GOMP_LAUNCH_ASYNC, NULL_TREE, i_async));
>         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
> cc1plus: all warnings being treated as errors
> make[3]: *** [omp-low.o] Error 1
> make[3]: *** Waiting for unfinished jobs....
> rm gcov-tool.pod gpl.pod cpp.pod gfdl.pod fsf-funding.pod gcc.pod gcov.pod
> make[3]: Leaving directory `/home/qwer/gcc/objdir/gcc'
> make[2]: *** [all-stagefeedback-gcc] Error 2
> make[2]: Leaving directory `/home/qwer/gcc/objdir'
> make[1]: *** [stagefeedback-bubble] Error 2
> make[1]: Leaving directory `/home/qwer/gcc/objdir'
> make: *** [profiledbootstrap] Error 2
>
> can someone help and tell me what i am doing wrong?
Check if passing --disable-werror option to configure helps.

Regards,
Prathamesh
>
> thanks.
> raphael.