[Bug middle-end/57089] New: [4.9 Regression] ICE in verify_loop_structure, at cfgloop.c:1647

[Joost.VandeVondele at mat dot ethz.ch]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57089

             Bug #: 57089
           Summary: [4.9 Regression] ICE in  verify_loop_structure, at
                    cfgloop.c:1647
    Classification: Unclassified
           Product: gcc
           Version: 4.9.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: middle-end
        AssignedTo: unassig...@gcc.gnu.org
        ReportedBy: joost.vandevond...@mat.ethz.ch


rev 198328 is still OK, 198353 fails.

> cat bug.f90 
  SUBROUTINE T()
    INTEGER            :: npoints, grad_deriv
    SELECT CASE(grad_deriv)
    CASE (0)
       !$omp do
       DO ii=1,npoints
       END DO
    END SELECT
  END SUBROUTINE 

> gfortran -fopenmp -c -O2 bug.f90 
bug.f90: In function ‘t’:
bug.f90:9:0: error: loop with header 7 not in loop tree
   END SUBROUTINE 
 ^
bug.f90:9:0: internal compiler error: in verify_loop_structure, at
cfgloop.c:1647
0x6b4665 verify_loop_structure()
    ../../gcc/gcc/cfgloop.c:1647
0x89ab3d loop_optimizer_init(unsigned int)
    ../../gcc/gcc/loop-init.c:109
0xa7ff23 perform_tree_ssa_dce
    ../../gcc/gcc/tree-ssa-dce.c:1554