re PR fortran/88047 (ICE in gfc_find_vtab, at fortran/class.c:2843)

2019-01-08  Janus Weil  <janus@gcc.gnu.org>

	PR fortran/88047
	* class.c (gfc_find_vtab): For polymorphic typespecs, the components of
	the class container may not be available (in case of invalid code).

2019-01-08  Janus Weil  <janus@gcc.gnu.org>

	PR fortran/88047
	* gfortran.dg/class_69.f90: New test case.

From-SVN: r267735

gcc/fortran/ChangeLog

+2019-01-08  Janus Weil  <janus@gcc.gnu.org>
+
+	PR fortran/88047
+	* class.c (gfc_find_vtab): For polymorphic typespecs, the components of
+	the class container may not be available (in case of invalid code).
+
 2019-01-08  Richard Biener  <rguenther@suse.de>
 
 	PR fortran/88611

gcc/fortran/class.c

@@ -2846,7 +2846,10 @@ gfc_find_vtab (gfc_typespec *ts)
     case BT_DERIVED:
       return gfc_find_derived_vtab (ts->u.derived);
     case BT_CLASS:
-      return gfc_find_derived_vtab (ts->u.derived->components->ts.u.derived);
+      if (ts->u.derived->components && ts->u.derived->components->ts.u.derived)
+	return gfc_find_derived_vtab (ts->u.derived->components->ts.u.derived);
+      else
+	return NULL;
     default:
       return find_intrinsic_vtab (ts);
     }

gcc/testsuite/ChangeLog

+2019-01-08  Janus Weil  <janus@gcc.gnu.org>
+
+	PR fortran/88047
+	* gfortran.dg/class_69.f90: New test case.
+
 2019-01-08  H.J. Lu  <hongjiu.lu@intel.com>
 
 	PR target/88717

gcc/testsuite/gfortran.dg/class_69.f90

+! { dg-do compile }
+!
+! PR 88047: [9 Regression] ICE in gfc_find_vtab, at fortran/class.c:2843
+!
+! Contributed by G. Steinmetz <gscfq@t-online.de>
+
+subroutine sub_a
+   type t
+   end type
+   class(t) :: x(2)                   ! { dg-error "must be dummy, allocatable or pointer" }
+   class(t), parameter :: a(2) = t()  ! { dg-error "cannot have the PARAMETER attribute" }
+   x = a                              ! { dg-error "Nonallocatable variable must not be polymorphic in intrinsic assignment" }
+end
+
+subroutine sub_b
+   type t
+      integer :: n
+   end type
+   class(t) :: a, x                   ! { dg-error "must be dummy, allocatable or pointer" }
+   x = a                              ! { dg-error "Nonallocatable variable must not be polymorphic in intrinsic assignment" }
+end