Bug in Intel MPI Fortran compiler version 15

Dear All,

There appears to be an obscure bug in version 15 of the Fortran compiler involving MPI, OpenMP and string passing all together.

We're running on Intel hardware under Linux. First the compiler:

mpif90 --version

ifort (IFORT) 15.0.3 20150407
Copyright (C) 1985-2015 Intel Corporation.  All rights reserved.

... now the smallest code I could devise which still has the bug:

program test
implicit none
integer i
!$OMP PARALLEL DEFAULT(SHARED)
!$OMP DO
do i=1,10
  call foo
end do
!$OMP END DO
!$OMP END PARALLEL
end program

subroutine foo
implicit none
character(256) str
call bar(str)
return
end subroutine

subroutine bar(str)
implicit none
character(*), intent(out) :: str
write(str,'(I1)') 1
return
end subroutine

... compiling with:

mpif90 -openmp test.f90

... results in code which crashes randomly with OMP_NUM_THREADS greater than one. This does not occur with version 14 of the compiler.

Regards,

John.