| /* Implementation of the EXTENDS_TYPE_OF intrinsic. |
| Copyright (C) 2004-2021 Free Software Foundation, Inc. |
| Contributed by Janus Weil <janus@gcc.gnu.org>. |
| |
| This file is part of the GNU Fortran runtime library (libgfortran). |
| |
| Libgfortran is free software; you can redistribute it and/or |
| modify it under the terms of the GNU General Public |
| License as published by the Free Software Foundation; either |
| version 3 of the License, or (at your option) any later version. |
| |
| Libgfortran is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| GNU General Public License for more details. |
| |
| Under Section 7 of GPL version 3, you are granted additional |
| permissions described in the GCC Runtime Library Exception, version |
| 3.1, as published by the Free Software Foundation. |
| |
| You should have received a copy of the GNU General Public License and |
| a copy of the GCC Runtime Library Exception along with this program; |
| see the files COPYING3 and COPYING.RUNTIME respectively. If not, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| |
| #include "libgfortran.h" |
| |
| |
| typedef struct vtype |
| { |
| GFC_INTEGER_4 hash; |
| size_t size; |
| struct vtype *extends; |
| } |
| vtype; |
| |
| |
| extern GFC_LOGICAL_4 is_extension_of (struct vtype *, struct vtype *); |
| export_proto(is_extension_of); |
| |
| |
| /* This is a helper function for the F2003 intrinsic EXTENDS_TYPE_OF. |
| While EXTENDS_TYPE_OF accepts CLASS or TYPE arguments, this one here gets |
| passed the corresponding vtabs. Each call to EXTENDS_TYPE_OF is translated |
| to a call to is_extension_of. */ |
| |
| GFC_LOGICAL_4 |
| is_extension_of (struct vtype *v1, struct vtype *v2) |
| { |
| /* Assume that only unlimited polymorphic entities will pass NULL v1 or v2 |
| if they are unallocated or disassociated. */ |
| |
| if (!v2) |
| return 1; |
| if (!v1) |
| return 0; |
| |
| while (v1) |
| { |
| if (v1->hash == v2->hash) return 1; |
| v1 = v1->extends; |
| } |
| return 0; |
| } |