[Bug fortran/92587] New: Compiler is unable to generate finalization wrapper

[liakhdi at ornl dot gov]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92587

            Bug ID: 92587
           Summary: Compiler is unable to generate finalization wrapper
           Product: gcc
           Version: 9.2.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: liakhdi at ornl dot gov
  Target Milestone: ---

Created attachment 47304
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=47304&action=edit
Complete reproducer of the reported ICE

There is a regression ICE introduced in gfortran/9.x (all versions up to 9.2.0
produce this ICE). The compiler reports ICE in generate_finalization_wrapper
(see below). The complete reproducer is attached (please run make.sh to build
it). I could not reduce it yet to a single small source file as stripping
things off makes the ICE disappear, so I apologize for supplying multiple
source files. Importantly this code compiles fine with gfortran/8.x, so this
ICE was introduced in gfortran/9 very early, when gfortran/9 was not yet
released. My system is Ubuntu 16.04 with the gcc/9.2.0 release installed from
source.

gfortran -c -g tensor_recursive.F90

f951: internal compiler error: in generate_finalization_wrapper, at
fortran/class.c:2009
0x588c29 generate_finalization_wrapper
        /home/dima/src/gcc-9.2.0/gcc/fortran/class.c:2009
0x588c29 gfc_find_derived_vtab(gfc_symbol*)
        /home/dima/src/gcc-9.2.0/gcc/fortran/class.c:2484
0x5e1891 gfc_find_vtab(gfc_typespec*)
        /home/dima/src/gcc-9.2.0/gcc/fortran/class.c:2865
0x5e1891 gfc_find_vtab(gfc_typespec*)
        /home/dima/src/gcc-9.2.0/gcc/fortran/class.c:2855
0x62f9b2 gfc_match_assignment()
        /home/dima/src/gcc-9.2.0/gcc/fortran/match.c:1378
0x64f3f4 match_word
        /home/dima/src/gcc-9.2.0/gcc/fortran/parse.c:65
0x64f3f4 decode_statement
        /home/dima/src/gcc-9.2.0/gcc/fortran/parse.c:361
0x652f24 next_free
        /home/dima/src/gcc-9.2.0/gcc/fortran/parse.c:1241
0x652f24 next_statement
        /home/dima/src/gcc-9.2.0/gcc/fortran/parse.c:1473
0x655a89 parse_executable
        /home/dima/src/gcc-9.2.0/gcc/fortran/parse.c:5436
0x6563a1 parse_if_block
        /home/dima/src/gcc-9.2.0/gcc/fortran/parse.c:4079
0x6563a1 parse_executable
        /home/dima/src/gcc-9.2.0/gcc/fortran/parse.c:5329
0x6563a1 parse_if_block
        /home/dima/src/gcc-9.2.0/gcc/fortran/parse.c:4079
0x6563a1 parse_executable
        /home/dima/src/gcc-9.2.0/gcc/fortran/parse.c:5329
0x656e06 parse_progunit
        /home/dima/src/gcc-9.2.0/gcc/fortran/parse.c:5706
0x65715e parse_contained
        /home/dima/src/gcc-9.2.0/gcc/fortran/parse.c:5581
0x657e5e parse_module
        /home/dima/src/gcc-9.2.0/gcc/fortran/parse.c:5953
0x6582ad gfc_parse_file()
        /home/dima/src/gcc-9.2.0/gcc/fortran/parse.c:6256
0x6a170f gfc_be_parse_file
        /home/dima/src/gcc-9.2.0/gcc/fortran/f95-lang.c:204

Thanks,
Dmitry