X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fround.c;h=a1dbead444e3a0f01e701de0ebee3d5ccc736879;hb=b344de996cd51f8a2f2558a3172016b64d99c622;hp=df6232d51311ff3ba362740284189262ea9ace68;hpb=f19c2f156e388e1da7ab9b13250dfeb380c0ab84;p=gnulib.git

diff --git a/lib/round.c b/lib/round.c
index df6232d51..a1dbead44 100644
--- a/lib/round.c
+++ b/lib/round.c
@@ -1,5 +1,5 @@
 /* Round toward nearest, breaking ties away from zero.
-   Copyright (C) 2007 Free Software Foundation, Inc.
+   Copyright (C) 2007, 2010-2011 Free Software Foundation, Inc.
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -20,15 +20,20 @@
 
 #include <config.h>
 
-#include <float.h>
+/* Specification.  */
 #include <math.h>
 
+#include <float.h>
+
+#undef MIN
+
 #ifdef USE_LONG_DOUBLE
 # define ROUND roundl
 # define FLOOR floorl
 # define CEIL ceill
 # define DOUBLE long double
 # define MANT_DIG LDBL_MANT_DIG
+# define MIN LDBL_MIN
 # define L_(literal) literal##L
 # define HAVE_FLOOR_AND_CEIL HAVE_FLOORL_AND_CEILL
 #elif ! defined USE_FLOAT
@@ -37,6 +42,7 @@
 # define CEIL ceil
 # define DOUBLE double
 # define MANT_DIG DBL_MANT_DIG
+# define MIN DBL_MIN
 # define L_(literal) literal
 # define HAVE_FLOOR_AND_CEIL 1
 #else /* defined USE_FLOAT */
@@ -45,10 +51,18 @@
 # define CEIL ceilf
 # define DOUBLE float
 # define MANT_DIG FLT_MANT_DIG
+# define MIN FLT_MIN
 # define L_(literal) literal##f
 # define HAVE_FLOOR_AND_CEIL HAVE_FLOORF_AND_CEILF
 #endif
 
+/* -0.0.  See minus-zero.h.  */
+#if defined __hpux || defined __sgi || defined __ICC
+# define MINUS_ZERO (-MIN * MIN)
+#else
+# define MINUS_ZERO L_(-0.0)
+#endif
+
 /* If we're being included from test-round2[f].c, it already defined names for
    our round implementations.  Otherwise, pick the preferred implementation for
    this machine. */
@@ -114,39 +128,39 @@ FLOOR_FREE_ROUND (DOUBLE x)
     {
       /* Avoid rounding error for x = 0.5 - 2^(-MANT_DIG-1).  */
       if (z < L_(0.5))
-	z = L_(0.0);
+        z = L_(0.0);
       /* Avoid rounding errors for values near 2^k, where k >= MANT_DIG-1.  */
       else if (z < TWO_MANT_DIG)
-	{
-	  /* Add 0.5 to the absolute value.  */
-	  y = z += L_(0.5);
-	  /* Round to the next integer (nearest or up or down, doesn't
+        {
+          /* Add 0.5 to the absolute value.  */
+          y = z += L_(0.5);
+          /* Round to the next integer (nearest or up or down, doesn't
              matter).  */
-	  z += TWO_MANT_DIG;
-	  z -= TWO_MANT_DIG;
-	  /* Enforce rounding down.  */
-	  if (z > y)
-	    z -= L_(1.0);
-	}
+          z += TWO_MANT_DIG;
+          z -= TWO_MANT_DIG;
+          /* Enforce rounding down.  */
+          if (z > y)
+            z -= L_(1.0);
+        }
     }
   else if (z < L_(0.0))
     {
       /* Avoid rounding error for x = -(0.5 - 2^(-MANT_DIG-1)).  */
       if (z > - L_(0.5))
-	z = L_(0.0);
+        z = MINUS_ZERO;
       /* Avoid rounding errors for values near -2^k, where k >= MANT_DIG-1.  */
       else if (z > -TWO_MANT_DIG)
-	{
-	  /* Add 0.5 to the absolute value.  */
-	  y = z -= L_(0.5);
-	  /* Round to the next integer (nearest or up or down, doesn't
+        {
+          /* Add 0.5 to the absolute value.  */
+          y = z -= L_(0.5);
+          /* Round to the next integer (nearest or up or down, doesn't
              matter).  */
-	  z -= TWO_MANT_DIG;
-	  z += TWO_MANT_DIG;
-	  /* Enforce rounding up.  */
-	  if (z < y)
-	    z += L_(1.0);
-	}
+          z -= TWO_MANT_DIG;
+          z += TWO_MANT_DIG;
+          /* Enforce rounding up.  */
+          if (z < y)
+            z += L_(1.0);
+        }
     }
   return z;
 }