[Bug fortran/107362] New: Segfault for recursive class

[baradi09 at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107362

            Bug ID: 107362
           Summary: Segfault for recursive class
           Product: gcc
           Version: 12.2.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: baradi09 at gmail dot com
  Target Milestone: ---

When trying to build Fortuno (https://github.com/aradi/fortuno), our new
Fortran unit testing system, I encounter a segfault with GFortran. The problem
can be reduced to the following MWE:

[details: failureinfo.f90]
module fortuno_failureinfo
  implicit none

  type :: failure_info
    class(failure_info), allocatable :: previous
  end type failure_info

end module fortuno_failureinfo
[/details]

> gfortran -freport-bug -c failureinfo.f90 
gfortran: internal compiler error: Segmentation fault signal terminated program
f951
Please submit a full bug report, with preprocessed source.
See <https://github.com/conda-forge/ctng-compilers-feedstock/issues/new/choose>
for instructions.

Apparently, the problem is the "class(failure_info)" field within the derived
type. Turning it into "type(failure_info)" allows compilation.

I use GNU Fortran (conda-forge gcc 12.2.0-18) 12.2.0 on x86_64/Linux.

Thanks a lot for having a look at it in advance!