[Bug fortran/71860] New: ICE on pointing to null(mold), verify_gimple failed

[gerhard.steinmetz.fortran@t-online.de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71860

            Bug ID: 71860
           Summary: ICE on pointing to null(mold), verify_gimple failed
           Product: gcc
           Version: 7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gerhard.steinmetz.fortran@t-online.de
  Target Milestone: ---

ICE with experimental (--enable-checking=yes) versions 7, 6,
and maybe older.


$ cat z1.f90
program p
   class(*), pointer :: z
   z => null(z)
end


$ gfortran-6 -g -O0 -Wall -fcheck=all -fno-frontend-optimize z1.f90
$ a.out


$ gfortran-7 z1.f90            # release
$ a.out


$ gfortran-7-20160710 z1.f90   # experimental
z1.f90:1:0:

 program p

Error: conversion of register to a different size
VIEW_CONVERT_EXPR<struct __class__STAR_p>(_1);

z = VIEW_CONVERT_EXPR<struct __class__STAR_p>(_1);
z1.f90:1:0: internal compiler error: verify_gimple failed
0xc48e8d verify_gimple_in_seq(gimple*)
        ../../gcc/tree-cfg.c:4879
0x9c9ec2 gimplify_body(tree_node*, bool)
        ../../gcc/gimplify.c:11710
0x9ca256 gimplify_function_tree(tree_node*)
        ../../gcc/gimplify.c:11798
0x8360b7 cgraph_node::analyze()
        ../../gcc/cgraphunit.c:625
0x839443 analyze_functions
        ../../gcc/cgraphunit.c:1086
0x83a128 symbol_table::finalize_compilation_unit()
        ../../gcc/cgraphunit.c:2543