[Bug fortran/95613] New: ICE in main_block_label, at tree-cfg.c:1455

[gs...@t-online.de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95613

            Bug ID: 95613
           Summary: ICE in main_block_label, at tree-cfg.c:1455
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gs...@t-online.de
  Target Milestone: ---

Affects versions down to at least r5 :


$ cat z1.f90
program p
   select case (0)
 2 end select
   goto 2
end


$ cat z2.f90
program p
   select case (0)
 2 end select
   stop
   goto 2
end


$ cat z3.f90
program p
   select case (0)
   case (2:1)
 2    stop
   end select
   goto 2
end


$ cat z4.f90
program p
   select case (0)
   case (2:1)
      2 stop
   case (3)
      goto 2
   end select
end


$ gfortran-11-20200607 -c z1.f90
z1.f90:3:2:

    3 |  2 end select
      |  1
    4 |    goto 2
      |         2
Warning: Legacy Extension: Label at (1) is not in the same block as the GOTO
statement at (2)
during GIMPLE pass: cfg
z1.f90:1:0:

    1 | program p
      |
internal compiler error: Segmentation fault
0xbc593f crash_signal
        ../../gcc/toplev.c:328
0xbf6d3b main_block_label
        ../../gcc/tree-cfg.c:1455
0xbf7271 cleanup_dead_labels()
        ../../gcc/tree-cfg.c:1639
0xc0186b build_gimple_cfg
        ../../gcc/tree-cfg.c:238
0xc0186b execute_build_cfg
        ../../gcc/tree-cfg.c:369
0xc0186b execute
        ../../gcc/tree-cfg.c:405