auto import from //depot/cupcake/@135843
diff --git a/libm/src/s_nextafterl.c b/libm/src/s_nextafterl.c
new file mode 100644
index 0000000..eacfd33
--- /dev/null
+++ b/libm/src/s_nextafterl.c
@@ -0,0 +1,82 @@
+/* @(#)s_nextafter.c 5.1 93/09/24 */
+/*
+ * ====================================================
+ * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+ *
+ * Developed at SunPro, a Sun Microsystems, Inc. business.
+ * Permission to use, copy, modify, and distribute this
+ * software is freely granted, provided that this notice
+ * is preserved.
+ * ====================================================
+ */
+
+#ifndef lint
+static char rcsid[] = "$FreeBSD: src/lib/msun/src/s_nextafterl.c,v 1.1 2005/03/07 04:56:46 das Exp $";
+#endif
+
+/* IEEE functions
+ * nextafter(x,y)
+ * return the next machine floating-point number of x in the
+ * direction toward y.
+ * Special cases:
+ */
+
+#include <sys/cdefs.h>
+#include <float.h>
+
+#include "fpmath.h"
+#include "math.h"
+#include "math_private.h"
+
+#if LDBL_MAX_EXP != 0x4000
+#error "Unsupported long double format"
+#endif
+
+long double
+nextafterl(long double x, long double y)
+{
+ volatile long double t;
+ union IEEEl2bits ux, uy;
+
+ ux.e = x;
+ uy.e = y;
+
+ if ((ux.bits.exp == 0x7fff &&
+ ((ux.bits.manh&~LDBL_NBIT)|ux.bits.manl) != 0) ||
+ (uy.bits.exp == 0x7fff &&
+ ((uy.bits.manh&~LDBL_NBIT)|uy.bits.manl) != 0))
+ return x+y; /* x or y is nan */
+ if(x==y) return y; /* x=y, return y */
+ if(x==0.0) {
+ ux.bits.manh = 0; /* return +-minsubnormal */
+ ux.bits.manl = 1;
+ ux.bits.sign = uy.bits.sign;
+ t = ux.e*ux.e;
+ if(t==ux.e) return t; else return ux.e; /* raise underflow flag */
+ }
+ if(x>0.0 ^ x<y) { /* x -= ulp */
+ if(ux.bits.manl==0) {
+ if ((ux.bits.manh&~LDBL_NBIT)==0)
+ ux.bits.exp -= 1;
+ ux.bits.manh = (ux.bits.manh - 1) | (ux.bits.manh & LDBL_NBIT);
+ }
+ ux.bits.manl -= 1;
+ } else { /* x += ulp */
+ ux.bits.manl += 1;
+ if(ux.bits.manl==0) {
+ ux.bits.manh = (ux.bits.manh + 1) | (ux.bits.manh & LDBL_NBIT);
+ if ((ux.bits.manh&~LDBL_NBIT)==0)
+ ux.bits.exp += 1;
+ }
+ }
+ if(ux.bits.exp==0x7fff) return x+x; /* overflow */
+ if(ux.bits.exp==0) { /* underflow */
+ mask_nbit_l(ux);
+ t = ux.e * ux.e;
+ if(t!=ux.e) /* raise underflow flag */
+ return ux.e;
+ }
+ return ux.e;
+}
+
+__strong_reference(nextafterl, nexttowardl);