[Bug fortran/50564] New: [4.7 Regression] Front-end optimization - ICE with FORALL

[burnus at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50564

             Bug #: 50564
           Summary: [4.7 Regression] Front-end optimization - ICE with
                    FORALL
    Classification: Unclassified
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: fortran
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: burnus@gcc.gnu.org
                CC: abenson@caltech.edu, tkoenig@gcc.gnu.org


Reported by Andrew Benson at
http://gcc.gnu.org/ml/fortran/2011-09/msg00154.html

With -ffrontend-optimize, gfortran ICEs with
  internal compiler error: in gfc_trans_forall_1, at fortran/trans-stmt.c:3796

Workaround: -fno-frontend-optimize
Said to be a 4.7 regression.

Test case:

program test
  implicit none
  double precision, allocatable, dimension(:) :: timeSteps
  integer                                     :: iTime
  double precision                            :: ratio
  forall(iTime=1:2)
     timeSteps(iTime)=ratio**(dble(iTime)-0.5d0)-ratio**(dble(iTime)-1.5d0)
  end forall
end program test