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+/**
+ * This file has no copyright assigned and is placed in the Public Domain.
+ * This file is part of the mingw-w64 runtime package.
+ * No warranty is given; refer to the file DISCLAIMER.PD within this package.
+ */
+/*
+ nexttoward.c
+ Contributed by Danny Smith <dannysmith@users.sourceforge.net>
+ No copyright claimed, absolutely no warranties.
+
+ 2005-05-10
+*/
+
+#include <math.h>
+
+double
+nexttoward (double x, long double y)
+{
+ union
+ {
+ double d;
+ unsigned long long ll;
+ } u;
+
+ long double xx = x;
+
+ if (isnan (y) || isnan (x))
+ return x + y;
+
+ if (xx == y)
+ /* nextafter (0.0, -O.0) should return -0.0. */
+ return y;
+ u.d = x;
+ if (x == 0.0)
+ {
+ u.ll = 1;
+ return y > 0.0L ? u.d : -u.d;
+ }
+
+ /* Non-extended encodings are lexicographically ordered,
+ with implicit "normal" bit. */
+ if (((x > 0.0) ^ (y > xx)) == 0)
+ u.ll++;
+ else
+ u.ll--;
+ return u.d;
+}