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diff --git a/ports/sysdeps/mips/bits/nan.h b/ports/sysdeps/mips/bits/nan.h
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+/* `NAN' constant for IEEE 754 machines.
+ Copyright (C) 1992, 1996, 1997, 1999, 2002, 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, see
+ <http://www.gnu.org/licenses/>. */
+
+#ifndef _MATH_H
+# error "Never use <bits/nan.h> directly; include <math.h> instead."
+#endif
+
+
+/* IEEE Not A Number (QNaN). Note that MIPS has the QNaN and SNaN patterns
+ reversed compared to most other architectures. The IEEE spec left
+ the definition of this open to implementations, and for MIPS the top
+ bit of the mantissa must be SET to indicate a SNaN. */
+
+#if __GNUC_PREREQ(3,3)
+
+# define NAN (__builtin_nanf(""))
+
+#elif defined __GNUC__
+
+# define NAN \
+ (__extension__ \
+ ((union { unsigned __l __attribute__((__mode__(__SI__))); float __d; }) \
+ { __l: 0x7fbfffffUL }).__d)
+
+#else
+
+# include <endian.h>
+
+# if __BYTE_ORDER == __BIG_ENDIAN
+# define __nan_bytes { 0x7f, 0xbf, 0xff, 0xff }
+# endif
+# if __BYTE_ORDER == __LITTLE_ENDIAN
+# define __nan_bytes { 0xff, 0xff, 0xbf, 0x7f }
+# endif
+
+static union { unsigned char __c[4]; float __d; } __nan_union = { __nan_bytes };
+# define NAN (__nan_union.__d)
+
+#endif /* GCC. */