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+/* Default `INFINITY' constant.
+   Copyright (C) 2004 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C 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 2.1 of the License, or (at your option) any later version.
+
+   The GNU C 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 the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#ifndef _MATH_H
+# error "Never use <bits/inf.h> directly; include <math.h> instead."
+#endif
+
+/* If we don't have real infinity, then we're supposed to produce a float
+   value that overflows at translation time, which is required to produce
+   a diagnostic.  GCC's __builtin_inff produces a quite nice diagnostic
+   that tells the user that the target doesn't support infinities.  */
+
+#if __GNUC_PREREQ(3,3)
+# define INFINITY	(__builtin_inff())
+#else
+# define INFINITY	(1e9999f)
+#endif