[Bug fortran/85603] New: ICE with character array substring assignment

[w6ws at earthlink dot net]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85603

            Bug ID: 85603
           Summary: ICE with character array substring assignment
           Product: gcc
           Version: 9.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: w6ws at earthlink dot net
  Target Milestone: ---

The following test case causes an ICE.  First noticed with v5.4, but also
happens with v4.8 and a 4/26/2018 snapshot of v9.0.0.  Intel and NAG compile
and run this.  PGI v17.10 also gets an ICE...:

program strlen_bug
  implicit none

  character(:), allocatable :: strings(:)
  integer :: maxlen

  strings = [ character(32) ::  &
      'short',  &
      'somewhat longer' ]
  maxlen = maxval (len_trim (strings))
  print *, 'max length =', maxlen
  ! causes ICE !
  strings = strings(:)(:maxlen)
  print *, strings

end program

wws@w6ws-4:/rootsda5/home/wws/fortran/array_cons$
/usr/local/gcc-trunk/bin/gfortran --version
GNU Fortran (GCC) 9.0.0 20180426 (experimental)
Copyright (C) 2018 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

wws@w6ws-4:/rootsda5/home/wws/fortran/array_cons$
/usr/local/gcc-trunk/bin/gfortran strlen_bug.f90
strlen_bug.f90:13:0:

   strings = strings(:)(:maxlen)

internal compiler error: Segmentation fault
0xce260f crash_signal
        ../../gcc-trunk/gcc/toplev.c:325
0x7722a7 gfc_alloc_allocatable_for_assignment(gfc_loopinfo*, gfc_expr*,
gfc_expr*)
        ../../gcc-trunk/gcc/fortran/trans-array.c:9915
0x7a3c24 gfc_trans_assignment_1
        ../../gcc-trunk/gcc/fortran/trans-expr.c:10329
0x754537 trans_code
        ../../gcc-trunk/gcc/fortran/trans.c:1828
0x7e7b2f gfc_trans_block_construct(gfc_code*)
        ../../gcc-trunk/gcc/fortran/trans-stmt.c:2058
0x754327 trans_code
        ../../gcc-trunk/gcc/fortran/trans.c:1924
0x788f45 gfc_generate_function_code(gfc_namespace*)
        ../../gcc-trunk/gcc/fortran/trans-decl.c:6507
0x7081d0 translate_all_program_units
        ../../gcc-trunk/gcc/fortran/parse.c:6121
0x7081d0 gfc_parse_file()
        ../../gcc-trunk/gcc/fortran/parse.c:6324
0x75107f gfc_be_parse_file
        ../../gcc-trunk/gcc/fortran/f95-lang.c:204
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.
wws@w6ws-4:/rootsda5/home/wws/fortran/array_cons$