[Bug fortran/80304] New: do-concurrent dosn't work well with gfortran 7.

["chinoune.mehdi at hotmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80304

            Bug ID: 80304
           Summary: do-concurrent dosn't work well with gfortran 7.
           Product: gcc
           Version: 7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: chinoune.mehdi at hotmail dot com
  Target Milestone: ---

Created attachment 41117
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=41117&action=edit
the test program

with gfortran my program generate different results with normal-do and
do-concurrent loop with optimization (-O and up). while it gives the same
results with gfortran 5.4.0 and gfortran 6.3.0 .
my build :
Target: x86_64-pc-linux-gnu
Configured with: ../configure --disable-multilib --prefix=/home/mehdi/gcc-7/
--program-suffix=-7 --enable-language=fortran --disable-bootstrap
--with-system-zlib --with-arch=native 
Thread model:posix 
gcc version 7.0.1 20170402 (experimental) (GCC)

my cpu is intel Core i7-4700MQ ( haswell core-i7)