--- /dev/null
+/* GTK - The GIMP Toolkit
+ * Copyright (C) 2011 Chun-wei Fan <fanc999@yahoo.com.tw>
+ *
+ * Author: Chun-wei Fan <fanc999@yahoo.com.tw>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <float.h>
+
+#ifndef HAVE_ISNAN
+/* it seems of the supported compilers only */
+/* MSVC does not have isnan(), but it does
+/* have _isnan() which does the same as isnan() */
+static inline gboolean
+isnan (double x)
+{
+ return _isnan (x);
+}
+#endif
+
+#ifndef HAVE_ISINF
+/* Unfortunately MSVC does not have finite() */
+/* but it does have _finite() which is the same */
+/* as finite() except when x is a NaN */
+static inline gboolean
+isinf (double x)
+{
+ return (!_finite (x) && !_isnan (x));
+}
+#endif