Add libgit compatibility header

common/git/kicad_git_compat.h

@@ -0,0 +1,34 @@
+/*
+ * This program source code file is part of KiCad, a free EDA CAD application.
+ *
+ * Copyright (C) 2023 KiCad Developers, see AUTHORS.TXT for contributors.
+ *
+ * This program 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.
+ *
+ * This program 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, you may find one here:
+ * http://www.gnu.org/licenses/gpl-3.0.html
+ * or you may search the http://www.gnu.org website for the version 3 license,
+ * or you may write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
+ */
+
+#ifndef KICAD_GIT_COMPAT_H_
+#define KICAD_GIT_COMPAT_H_
+
+#include <git2.h>
+
+// GIT_BUF_INIT was added in libgit2 1.4
+#ifndef GIT_BUF_INIT
+#define GIT_BUF_INIT { NULL, 0, 0 }
+#endif
+
+#endif // KICAD_GIT_COMPAT_H_