[Fortran] Fix to strict associate check (PR93427)

PR fortran/93427
        * resolve.c (resolve_assoc_var): Remove too strict check.
        * gfortran.dg/associate_51.f90: Update test case.

        PR fortran/93427
        * gfortran.dg/associate_52.f90: New.

gcc/fortran/ChangeLog

@@ -1,3 +1,9 @@
+2020-02-03  Tobias Burnus  <tobias@codesourcery.com>
+
+	PR fortran/93427
+	* resolve.c (resolve_assoc_var): Remove too strict check.
+	* gfortran.dg/associate_51.f90: Update test case.
+
 2020-02-01  Jakub Jelinek  <jakub@redhat.com>
 
 	PR fortran/92305

gcc/fortran/resolve.c

@@ -8846,8 +8846,7 @@ resolve_assoc_var (gfc_symbol* sym, bool resolve_target)
 
       if (tsym->attr.subroutine
 	  || tsym->attr.external
-	  || (tsym->attr.function
-	      && (tsym->result != tsym || tsym->attr.recursive)))
+	  || (tsym->attr.function && tsym->result != tsym))
 	{
 	  gfc_error ("Associating entity %qs at %L is a procedure name",
 		     tsym->name, &target->where);

gcc/testsuite/ChangeLog

@@ -1,3 +1,8 @@
+2020-02-03  Tobias Burnus  <tobias@codesourcery.com>
+
+	PR fortran/93427
+	* gfortran.dg/associate_52.f90: New.
+
 2020-02-03  Jakub Jelinek  <jakub@redhat.com>
 
 	PR target/93533

gcc/testsuite/gfortran.dg/associate_51.f90

@@ -14,7 +14,14 @@ end
 recursive function f2()
   associate (y1 => f2()) ! { dg-error "Invalid association target" }
   end associate          ! { dg-error "Expecting END FUNCTION statement" }
-  associate (y2 => f2)   ! { dg-error "is a procedure name" }
+end
+
+recursive function f3()
+  associate (y1 => f3)
+    print *, y1()  ! { dg-error "Expected array subscript" }
+  end associate
+  associate (y2 => f3) ! { dg-error "Associate-name 'y2' at \\(1\\) is used as array" }
+    print *, y2(1)
   end associate
 end
 

gcc/testsuite/gfortran.dg/associate_52.f90

@@ -0,0 +1,24 @@
+! { dg-do compile }
+!
+! PR fortran/93427
+!
+! Contributed by Andrew Benson
+!
+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