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diff --git a/REORG.TODO/sysdeps/ieee754/dbl-64/e_log10.c b/REORG.TODO/sysdeps/ieee754/dbl-64/e_log10.c
new file mode 100644
index 0000000000..bf40bca874
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+++ b/REORG.TODO/sysdeps/ieee754/dbl-64/e_log10.c
@@ -0,0 +1,88 @@
+/* @(#)e_log10.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.
+ * ====================================================
+ */
+
+/* __ieee754_log10(x)
+ * Return the base 10 logarithm of x
+ *
+ * Method :
+ *	Let log10_2hi = leading 40 bits of log10(2) and
+ *	    log10_2lo = log10(2) - log10_2hi,
+ *	    ivln10   = 1/log(10) rounded.
+ *	Then
+ *		n = ilogb(x),
+ *		if(n<0)  n = n+1;
+ *		x = scalbn(x,-n);
+ *		log10(x) := n*log10_2hi + (n*log10_2lo + ivln10*log(x))
+ *
+ * Note 1:
+ *	To guarantee log10(10**n)=n, where 10**n is normal, the rounding
+ *	mode must set to Round-to-Nearest.
+ * Note 2:
+ *	[1/log(10)] rounded to 53 bits has error  .198   ulps;
+ *	log10 is monotonic at all binary break points.
+ *
+ * Special cases:
+ *	log10(x) is NaN with signal if x < 0;
+ *	log10(+INF) is +INF with no signal; log10(0) is -INF with signal;
+ *	log10(NaN) is that NaN with no signal;
+ *	log10(10**N) = N  for N=0,1,...,22.
+ *
+ * Constants:
+ * The hexadecimal values are the intended ones for the following constants.
+ * The decimal values may be used, provided that the compiler will convert
+ * from decimal to binary accurately enough to produce the hexadecimal values
+ * shown.
+ */
+
+#include <math.h>
+#include <math_private.h>
+#include <fix-int-fp-convert-zero.h>
+
+static const double two54 = 1.80143985094819840000e+16;         /* 0x43500000, 0x00000000 */
+static const double ivln10 = 4.34294481903251816668e-01;        /* 0x3FDBCB7B, 0x1526E50E */
+static const double log10_2hi = 3.01029995663611771306e-01;     /* 0x3FD34413, 0x509F6000 */
+static const double log10_2lo = 3.69423907715893078616e-13;     /* 0x3D59FEF3, 0x11F12B36 */
+
+double
+__ieee754_log10 (double x)
+{
+  double y, z;
+  int32_t i, k, hx;
+  u_int32_t lx;
+
+  EXTRACT_WORDS (hx, lx, x);
+
+  k = 0;
+  if (hx < 0x00100000)
+    {                           /* x < 2**-1022  */
+      if (__glibc_unlikely (((hx & 0x7fffffff) | lx) == 0))
+	return -two54 / __fabs (x);	/* log(+-0)=-inf  */
+      if (__glibc_unlikely (hx < 0))
+	return (x - x) / (x - x);       /* log(-#) = NaN */
+      k -= 54;
+      x *= two54;               /* subnormal number, scale up x */
+      GET_HIGH_WORD (hx, x);
+    }
+  if (__glibc_unlikely (hx >= 0x7ff00000))
+    return x + x;
+  k += (hx >> 20) - 1023;
+  i = ((u_int32_t) k & 0x80000000) >> 31;
+  hx = (hx & 0x000fffff) | ((0x3ff - i) << 20);
+  y = (double) (k + i);
+  if (FIX_INT_FP_CONVERT_ZERO && y == 0.0)
+    y = 0.0;
+  SET_HIGH_WORD (x, hx);
+  z = y * log10_2lo + ivln10 * __ieee754_log (x);
+  return z + y * log10_2hi;
+}
+
+strong_alias (__ieee754_log10, __log10_finite)