[Bug fortran/93427] New: Rejects valid with pointer result from recursive function

[abensonca at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93427

            Bug ID: 93427
           Summary: Rejects valid with pointer result from recursive
                    function
           Product: gcc
           Version: 10.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: abensonca at gmail dot com
  Target Milestone: ---

The following code fails to compile (using git commit
472dc648ce3e7661762931d584d239611ddca964):

module a

type :: t
end type t

contains

recursive function b()
  class(t), pointer :: b
  type(t) :: c
  allocate(t :: b)
  select type (b)
  type is (t)
     b=c
  end select
end function b

end module a



$ gfortran -v
Using built-in specs.
COLLECT_GCC=gfortran
COLLECT_LTO_WRAPPER=/home/abenson/Galacticus/Tools/libexec/gcc/x86_64-pc-linux-gnu/10.0.1/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: ../gcc-git/configure --prefix=/home/abenson/Galacticus/Tools
--enable-languages=c,c++,fortran
 --disable-multilib
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 10.0.1 20200124 (experimental) (GCC)


$ gfortran -c p.F90 -o p.o                                                      
p.F90:12:15:

   12 |   select type (b)
      |               1
Error: Associating entity 'b' at (1) is a procedure name
p.F90:14:5:

   14 |      b=c
      |     1
Error: 'b' at (1) associated to vector-indexed target cannot be used in a
variable definition context (assignment)


The code compiles successfully using ifort 18.0.1. Removing the "recursive"
attribute, or specifying a "result()" variable makes the errors go away.