scm_wta_* procedures replace SCM_WTA_* macros
[bpt/guile.git] / libguile / numbers.c
index b8cfa5d..24ae2bc 100644 (file)
@@ -45,6 +45,8 @@
 #  include <config.h>
 #endif
 
+#include <verify.h>
+
 #include <math.h>
 #include <string.h>
 #include <unicase.h>
@@ -134,9 +136,9 @@ static double acosh (double x) { return log (x + sqrt (x * x - 1)); }
 static double atanh (double x) { return 0.5 * log ((1 + x) / (1 - x)); }
 #endif
 
-/* mpz_cmp_d in gmp 4.1.3 doesn't recognise infinities, so xmpz_cmp_d uses
-   an explicit check.  In some future gmp (don't know what version number),
-   mpz_cmp_d is supposed to do this itself.  */
+/* mpz_cmp_d in GMP before 4.2 didn't recognise infinities, so
+   xmpz_cmp_d uses an explicit check.  Starting with GMP 4.2 (released
+   in March 2006), mpz_cmp_d now handles infinities properly.  */
 #if 1
 #define xmpz_cmp_d(z, d)                                \
   (isinf (d) ? (d < 0.0 ? 1 : -1) : mpz_cmp_d (z, d))
@@ -146,7 +148,7 @@ static double atanh (double x) { return 0.5 * log ((1 + x) / (1 - x)); }
 
 
 #if defined (GUILE_I)
-#if HAVE_COMPLEX_DOUBLE
+#if defined HAVE_COMPLEX_DOUBLE
 
 /* For an SCM object Z which is a complex number (ie. satisfies
    SCM_COMPLEXP), return its value as a C level "complex double". */
@@ -316,16 +318,15 @@ scm_i_dbl2num (double u)
    we need to use mpz_getlimbn.  mpz_tstbit is not right, it treats
    negatives as twos complement.
 
-   In current gmp 4.1.3, mpz_get_d rounding is unspecified.  It ends up
-   following the hardware rounding mode, but applied to the absolute value
-   of the mpz_t operand.  This is not what we want so we put the high
-   DBL_MANT_DIG bits into a temporary.  In some future gmp, don't know when,
-   mpz_get_d is supposed to always truncate towards zero.
+   In GMP before 4.2, mpz_get_d rounding was unspecified.  It ended up
+   following the hardware rounding mode, but applied to the absolute
+   value of the mpz_t operand.  This is not what we want so we put the
+   high DBL_MANT_DIG bits into a temporary.  Starting with GMP 4.2
+   (released in March 2006) mpz_get_d now always truncates towards zero.
 
-   ENHANCE-ME: The temporary init+clear to force the rounding in gmp 4.1.3
-   is a slowdown.  It'd be faster to pick out the relevant high bits with
-   mpz_getlimbn if we could be bothered coding that, and if the new
-   truncating gmp doesn't come out.  */
+   ENHANCE-ME: The temporary init+clear to force the rounding in GMP
+   before 4.2 is a slowdown.  It'd be faster to pick out the relevant
+   high bits with mpz_getlimbn.  */
 
 double
 scm_i_big2dbl (SCM b)
@@ -337,7 +338,12 @@ scm_i_big2dbl (SCM b)
 
 #if 1
   {
-    /* Current GMP, eg. 4.1.3, force truncation towards zero */
+    /* For GMP earlier than 4.2, force truncation towards zero */
+
+    /* FIXME: DBL_MANT_DIG is the number of base-`FLT_RADIX' digits,
+       _not_ the number of bits, so this code will break badly on a
+       system with non-binary doubles.  */
+
     mpz_t  tmp;
     if (bits > DBL_MANT_DIG)
       {
@@ -353,7 +359,7 @@ scm_i_big2dbl (SCM b)
       }
   }
 #else
-  /* Future GMP */
+  /* GMP 4.2 or later */
   result = mpz_get_d (SCM_I_BIG_MPZ (b));
 #endif
 
@@ -526,7 +532,7 @@ SCM_PRIMITIVE_GENERIC (scm_exact_p, "exact?", 1, 0, 0,
   else if (SCM_NUMBERP (x))
     return SCM_BOOL_T;
   else
-    SCM_WTA_DISPATCH_1 (g_scm_exact_p, x, 1, s_scm_exact_p);
+    return scm_wta_dispatch_1 (g_scm_exact_p, x, 1, s_scm_exact_p);
 }
 #undef FUNC_NAME
 
@@ -542,7 +548,7 @@ SCM_PRIMITIVE_GENERIC (scm_inexact_p, "inexact?", 1, 0, 0,
   else if (SCM_NUMBERP (x))
     return SCM_BOOL_F;
   else
-    SCM_WTA_DISPATCH_1 (g_scm_inexact_p, x, 1, s_scm_inexact_p);
+    return scm_wta_dispatch_1 (g_scm_inexact_p, x, 1, s_scm_inexact_p);
 }
 #undef FUNC_NAME
 
@@ -576,7 +582,7 @@ SCM_PRIMITIVE_GENERIC (scm_odd_p, "odd?", 1, 0, 0,
            return SCM_BOOL_F;
        }
     }
-  SCM_WTA_DISPATCH_1 (g_scm_odd_p, n, 1, s_scm_odd_p);
+  return scm_wta_dispatch_1 (g_scm_odd_p, n, 1, s_scm_odd_p);
 }
 #undef FUNC_NAME
 
@@ -610,7 +616,7 @@ SCM_PRIMITIVE_GENERIC (scm_even_p, "even?", 1, 0, 0,
            return SCM_BOOL_T;
        }
     }
-  SCM_WTA_DISPATCH_1 (g_scm_even_p, n, 1, s_scm_even_p);
+  return scm_wta_dispatch_1 (g_scm_even_p, n, 1, s_scm_even_p);
 }
 #undef FUNC_NAME
 
@@ -625,7 +631,7 @@ SCM_PRIMITIVE_GENERIC (scm_finite_p, "finite?", 1, 0, 0,
   else if (scm_is_real (x))
     return SCM_BOOL_T;
   else
-    SCM_WTA_DISPATCH_1 (g_scm_finite_p, x, 1, s_scm_finite_p);
+    return scm_wta_dispatch_1 (g_scm_finite_p, x, 1, s_scm_finite_p);
 }
 #undef FUNC_NAME
 
@@ -640,7 +646,7 @@ SCM_PRIMITIVE_GENERIC (scm_inf_p, "inf?", 1, 0, 0,
   else if (scm_is_real (x))
     return SCM_BOOL_F;
   else
-    SCM_WTA_DISPATCH_1 (g_scm_inf_p, x, 1, s_scm_inf_p);
+    return scm_wta_dispatch_1 (g_scm_inf_p, x, 1, s_scm_inf_p);
 }
 #undef FUNC_NAME
 
@@ -655,7 +661,7 @@ SCM_PRIMITIVE_GENERIC (scm_nan_p, "nan?", 1, 0, 0,
   else if (scm_is_real (x))
     return SCM_BOOL_F;
   else
-    SCM_WTA_DISPATCH_1 (g_scm_nan_p, x, 1, s_scm_nan_p);
+    return scm_wta_dispatch_1 (g_scm_nan_p, x, 1, s_scm_nan_p);
 }
 #undef FUNC_NAME
 
@@ -782,7 +788,7 @@ SCM_PRIMITIVE_GENERIC (scm_abs, "abs", 1, 0, 0,
                             SCM_FRACTION_DENOMINATOR (x));
     }
   else
-    SCM_WTA_DISPATCH_1 (g_scm_abs, x, 1, s_scm_abs);
+    return scm_wta_dispatch_1 (g_scm_abs, x, 1, s_scm_abs);
 }
 #undef FUNC_NAME
 
@@ -792,15 +798,15 @@ SCM_PRIMITIVE_GENERIC (scm_quotient, "quotient", 2, 0, 0,
        "Return the quotient of the numbers @var{x} and @var{y}.")
 #define FUNC_NAME s_scm_quotient
 {
-  if (SCM_LIKELY (SCM_I_INUMP (x)) || SCM_LIKELY (SCM_BIGP (x)))
+  if (SCM_LIKELY (scm_is_integer (x)))
     {
-      if (SCM_LIKELY (SCM_I_INUMP (y)) || SCM_LIKELY (SCM_BIGP (y)))
+      if (SCM_LIKELY (scm_is_integer (y)))
        return scm_truncate_quotient (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_quotient, x, y, SCM_ARG2, s_scm_quotient);
+       return scm_wta_dispatch_2 (g_scm_quotient, x, y, SCM_ARG2, s_scm_quotient);
     }
   else
-    SCM_WTA_DISPATCH_2 (g_scm_quotient, x, y, SCM_ARG1, s_scm_quotient);
+    return scm_wta_dispatch_2 (g_scm_quotient, x, y, SCM_ARG1, s_scm_quotient);
 }
 #undef FUNC_NAME
 
@@ -813,15 +819,15 @@ SCM_PRIMITIVE_GENERIC (scm_remainder, "remainder", 2, 0, 0,
        "@end lisp")
 #define FUNC_NAME s_scm_remainder
 {
-  if (SCM_LIKELY (SCM_I_INUMP (x)) || SCM_LIKELY (SCM_BIGP (x)))
+  if (SCM_LIKELY (scm_is_integer (x)))
     {
-      if (SCM_LIKELY (SCM_I_INUMP (y)) || SCM_LIKELY (SCM_BIGP (y)))
+      if (SCM_LIKELY (scm_is_integer (y)))
        return scm_truncate_remainder (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_remainder, x, y, SCM_ARG2, s_scm_remainder);
+       return scm_wta_dispatch_2 (g_scm_remainder, x, y, SCM_ARG2, s_scm_remainder);
     }
   else
-    SCM_WTA_DISPATCH_2 (g_scm_remainder, x, y, SCM_ARG1, s_scm_remainder);
+    return scm_wta_dispatch_2 (g_scm_remainder, x, y, SCM_ARG1, s_scm_remainder);
 }
 #undef FUNC_NAME
 
@@ -835,15 +841,15 @@ SCM_PRIMITIVE_GENERIC (scm_modulo, "modulo", 2, 0, 0,
        "@end lisp")
 #define FUNC_NAME s_scm_modulo
 {
-  if (SCM_LIKELY (SCM_I_INUMP (x)) || SCM_LIKELY (SCM_BIGP (x)))
+  if (SCM_LIKELY (scm_is_integer (x)))
     {
-      if (SCM_LIKELY (SCM_I_INUMP (y)) || SCM_LIKELY (SCM_BIGP (y)))
+      if (SCM_LIKELY (scm_is_integer (y)))
        return scm_floor_remainder (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_modulo, x, y, SCM_ARG2, s_scm_modulo);
+       return scm_wta_dispatch_2 (g_scm_modulo, x, y, SCM_ARG2, s_scm_modulo);
     }
   else
-    SCM_WTA_DISPATCH_2 (g_scm_modulo, x, y, SCM_ARG1, s_scm_modulo);
+    return scm_wta_dispatch_2 (g_scm_modulo, x, y, SCM_ARG1, s_scm_modulo);
 }
 #undef FUNC_NAME
 
@@ -864,10 +870,9 @@ static void
 two_valued_wta_dispatch_2 (SCM gf, SCM a1, SCM a2, int pos,
                           const char *subr, SCM *rp1, SCM *rp2)
 {
-  if (SCM_UNPACK (gf))
-    scm_i_extract_values_2 (scm_call_generic_2 (gf, a1, a2), rp1, rp2);
-  else
-    scm_wrong_type_arg (subr, pos, (pos == SCM_ARG1) ? a1 : a2);
+  SCM vals = scm_wta_dispatch_2 (gf, a1, a2, pos, subr);
+  
+  scm_i_extract_values_2 (vals, rp1, rp2);
 }
 
 SCM_DEFINE (scm_euclidean_quotient, "euclidean-quotient", 2, 0, 0,
@@ -999,8 +1004,8 @@ SCM_PRIMITIVE_GENERIC (scm_floor_quotient, "floor-quotient", 2, 0, 0,
       else if (SCM_FRACTIONP (y))
        return scm_i_exact_rational_floor_quotient (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_floor_quotient, x, y, SCM_ARG2,
-                           s_scm_floor_quotient);
+       return scm_wta_dispatch_2 (g_scm_floor_quotient, x, y, SCM_ARG2,
+                                   s_scm_floor_quotient);
     }
   else if (SCM_BIGP (x))
     {
@@ -1040,8 +1045,8 @@ SCM_PRIMITIVE_GENERIC (scm_floor_quotient, "floor-quotient", 2, 0, 0,
       else if (SCM_FRACTIONP (y))
        return scm_i_exact_rational_floor_quotient (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_floor_quotient, x, y, SCM_ARG2,
-                           s_scm_floor_quotient);
+       return scm_wta_dispatch_2 (g_scm_floor_quotient, x, y, SCM_ARG2,
+                                   s_scm_floor_quotient);
     }
   else if (SCM_REALP (x))
     {
@@ -1050,8 +1055,8 @@ SCM_PRIMITIVE_GENERIC (scm_floor_quotient, "floor-quotient", 2, 0, 0,
        return scm_i_inexact_floor_quotient
          (SCM_REAL_VALUE (x), scm_to_double (y));
       else
-       SCM_WTA_DISPATCH_2 (g_scm_floor_quotient, x, y, SCM_ARG2,
-                           s_scm_floor_quotient);
+       return scm_wta_dispatch_2 (g_scm_floor_quotient, x, y, SCM_ARG2,
+                                   s_scm_floor_quotient);
     }
   else if (SCM_FRACTIONP (x))
     {
@@ -1061,12 +1066,12 @@ SCM_PRIMITIVE_GENERIC (scm_floor_quotient, "floor-quotient", 2, 0, 0,
       else if (SCM_I_INUMP (y) || SCM_BIGP (y) || SCM_FRACTIONP (y))
        return scm_i_exact_rational_floor_quotient (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_floor_quotient, x, y, SCM_ARG2,
-                           s_scm_floor_quotient);
+       return scm_wta_dispatch_2 (g_scm_floor_quotient, x, y, SCM_ARG2,
+                                   s_scm_floor_quotient);
     }
   else
-    SCM_WTA_DISPATCH_2 (g_scm_floor_quotient, x, y, SCM_ARG1,
-                       s_scm_floor_quotient);
+    return scm_wta_dispatch_2 (g_scm_floor_quotient, x, y, SCM_ARG1,
+                               s_scm_floor_quotient);
 }
 #undef FUNC_NAME
 
@@ -1159,8 +1164,8 @@ SCM_PRIMITIVE_GENERIC (scm_floor_remainder, "floor-remainder", 2, 0, 0,
       else if (SCM_FRACTIONP (y))
        return scm_i_exact_rational_floor_remainder (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_floor_remainder, x, y, SCM_ARG2,
-                           s_scm_floor_remainder);
+       return scm_wta_dispatch_2 (g_scm_floor_remainder, x, y, SCM_ARG2,
+                                   s_scm_floor_remainder);
     }
   else if (SCM_BIGP (x))
     {
@@ -1195,8 +1200,8 @@ SCM_PRIMITIVE_GENERIC (scm_floor_remainder, "floor-remainder", 2, 0, 0,
       else if (SCM_FRACTIONP (y))
        return scm_i_exact_rational_floor_remainder (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_floor_remainder, x, y, SCM_ARG2,
-                           s_scm_floor_remainder);
+       return scm_wta_dispatch_2 (g_scm_floor_remainder, x, y, SCM_ARG2,
+                                   s_scm_floor_remainder);
     }
   else if (SCM_REALP (x))
     {
@@ -1205,8 +1210,8 @@ SCM_PRIMITIVE_GENERIC (scm_floor_remainder, "floor-remainder", 2, 0, 0,
        return scm_i_inexact_floor_remainder
          (SCM_REAL_VALUE (x), scm_to_double (y));
       else
-       SCM_WTA_DISPATCH_2 (g_scm_floor_remainder, x, y, SCM_ARG2,
-                           s_scm_floor_remainder);
+       return scm_wta_dispatch_2 (g_scm_floor_remainder, x, y, SCM_ARG2,
+                                   s_scm_floor_remainder);
     }
   else if (SCM_FRACTIONP (x))
     {
@@ -1216,12 +1221,12 @@ SCM_PRIMITIVE_GENERIC (scm_floor_remainder, "floor-remainder", 2, 0, 0,
       else if (SCM_I_INUMP (y) || SCM_BIGP (y) || SCM_FRACTIONP (y))
        return scm_i_exact_rational_floor_remainder (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_floor_remainder, x, y, SCM_ARG2,
-                           s_scm_floor_remainder);
+       return scm_wta_dispatch_2 (g_scm_floor_remainder, x, y, SCM_ARG2,
+                                   s_scm_floor_remainder);
     }
   else
-    SCM_WTA_DISPATCH_2 (g_scm_floor_remainder, x, y, SCM_ARG1,
-                       s_scm_floor_remainder);
+    return scm_wta_dispatch_2 (g_scm_floor_remainder, x, y, SCM_ARG1,
+                               s_scm_floor_remainder);
 }
 #undef FUNC_NAME
 
@@ -1534,8 +1539,8 @@ SCM_PRIMITIVE_GENERIC (scm_ceiling_quotient, "ceiling-quotient", 2, 0, 0,
       else if (SCM_FRACTIONP (y))
        return scm_i_exact_rational_ceiling_quotient (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_ceiling_quotient, x, y, SCM_ARG2,
-                           s_scm_ceiling_quotient);
+       return scm_wta_dispatch_2 (g_scm_ceiling_quotient, x, y, SCM_ARG2,
+                                   s_scm_ceiling_quotient);
     }
   else if (SCM_BIGP (x))
     {
@@ -1575,8 +1580,8 @@ SCM_PRIMITIVE_GENERIC (scm_ceiling_quotient, "ceiling-quotient", 2, 0, 0,
       else if (SCM_FRACTIONP (y))
        return scm_i_exact_rational_ceiling_quotient (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_ceiling_quotient, x, y, SCM_ARG2,
-                           s_scm_ceiling_quotient);
+       return scm_wta_dispatch_2 (g_scm_ceiling_quotient, x, y, SCM_ARG2,
+                                   s_scm_ceiling_quotient);
     }
   else if (SCM_REALP (x))
     {
@@ -1585,8 +1590,8 @@ SCM_PRIMITIVE_GENERIC (scm_ceiling_quotient, "ceiling-quotient", 2, 0, 0,
        return scm_i_inexact_ceiling_quotient
          (SCM_REAL_VALUE (x), scm_to_double (y));
       else
-       SCM_WTA_DISPATCH_2 (g_scm_ceiling_quotient, x, y, SCM_ARG2,
-                           s_scm_ceiling_quotient);
+       return scm_wta_dispatch_2 (g_scm_ceiling_quotient, x, y, SCM_ARG2,
+                                   s_scm_ceiling_quotient);
     }
   else if (SCM_FRACTIONP (x))
     {
@@ -1596,12 +1601,12 @@ SCM_PRIMITIVE_GENERIC (scm_ceiling_quotient, "ceiling-quotient", 2, 0, 0,
       else if (SCM_I_INUMP (y) || SCM_BIGP (y) || SCM_FRACTIONP (y))
        return scm_i_exact_rational_ceiling_quotient (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_ceiling_quotient, x, y, SCM_ARG2,
-                           s_scm_ceiling_quotient);
+       return scm_wta_dispatch_2 (g_scm_ceiling_quotient, x, y, SCM_ARG2,
+                                   s_scm_ceiling_quotient);
     }
   else
-    SCM_WTA_DISPATCH_2 (g_scm_ceiling_quotient, x, y, SCM_ARG1,
-                       s_scm_ceiling_quotient);
+    return scm_wta_dispatch_2 (g_scm_ceiling_quotient, x, y, SCM_ARG1,
+                               s_scm_ceiling_quotient);
 }
 #undef FUNC_NAME
 
@@ -1704,8 +1709,8 @@ SCM_PRIMITIVE_GENERIC (scm_ceiling_remainder, "ceiling-remainder", 2, 0, 0,
       else if (SCM_FRACTIONP (y))
        return scm_i_exact_rational_ceiling_remainder (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_ceiling_remainder, x, y, SCM_ARG2,
-                           s_scm_ceiling_remainder);
+       return scm_wta_dispatch_2 (g_scm_ceiling_remainder, x, y, SCM_ARG2,
+                                   s_scm_ceiling_remainder);
     }
   else if (SCM_BIGP (x))
     {
@@ -1740,8 +1745,8 @@ SCM_PRIMITIVE_GENERIC (scm_ceiling_remainder, "ceiling-remainder", 2, 0, 0,
       else if (SCM_FRACTIONP (y))
        return scm_i_exact_rational_ceiling_remainder (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_ceiling_remainder, x, y, SCM_ARG2,
-                           s_scm_ceiling_remainder);
+       return scm_wta_dispatch_2 (g_scm_ceiling_remainder, x, y, SCM_ARG2,
+                                   s_scm_ceiling_remainder);
     }
   else if (SCM_REALP (x))
     {
@@ -1750,8 +1755,8 @@ SCM_PRIMITIVE_GENERIC (scm_ceiling_remainder, "ceiling-remainder", 2, 0, 0,
        return scm_i_inexact_ceiling_remainder
          (SCM_REAL_VALUE (x), scm_to_double (y));
       else
-       SCM_WTA_DISPATCH_2 (g_scm_ceiling_remainder, x, y, SCM_ARG2,
-                           s_scm_ceiling_remainder);
+       return scm_wta_dispatch_2 (g_scm_ceiling_remainder, x, y, SCM_ARG2,
+                                   s_scm_ceiling_remainder);
     }
   else if (SCM_FRACTIONP (x))
     {
@@ -1761,12 +1766,12 @@ SCM_PRIMITIVE_GENERIC (scm_ceiling_remainder, "ceiling-remainder", 2, 0, 0,
       else if (SCM_I_INUMP (y) || SCM_BIGP (y) || SCM_FRACTIONP (y))
        return scm_i_exact_rational_ceiling_remainder (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_ceiling_remainder, x, y, SCM_ARG2,
-                           s_scm_ceiling_remainder);
+       return scm_wta_dispatch_2 (g_scm_ceiling_remainder, x, y, SCM_ARG2,
+                                   s_scm_ceiling_remainder);
     }
   else
-    SCM_WTA_DISPATCH_2 (g_scm_ceiling_remainder, x, y, SCM_ARG1,
-                       s_scm_ceiling_remainder);
+    return scm_wta_dispatch_2 (g_scm_ceiling_remainder, x, y, SCM_ARG1,
+                               s_scm_ceiling_remainder);
 }
 #undef FUNC_NAME
 
@@ -2066,8 +2071,8 @@ SCM_PRIMITIVE_GENERIC (scm_truncate_quotient, "truncate-quotient", 2, 0, 0,
       else if (SCM_FRACTIONP (y))
        return scm_i_exact_rational_truncate_quotient (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_truncate_quotient, x, y, SCM_ARG2,
-                           s_scm_truncate_quotient);
+       return scm_wta_dispatch_2 (g_scm_truncate_quotient, x, y, SCM_ARG2,
+                                   s_scm_truncate_quotient);
     }
   else if (SCM_BIGP (x))
     {
@@ -2107,8 +2112,8 @@ SCM_PRIMITIVE_GENERIC (scm_truncate_quotient, "truncate-quotient", 2, 0, 0,
       else if (SCM_FRACTIONP (y))
        return scm_i_exact_rational_truncate_quotient (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_truncate_quotient, x, y, SCM_ARG2,
-                           s_scm_truncate_quotient);
+       return scm_wta_dispatch_2 (g_scm_truncate_quotient, x, y, SCM_ARG2,
+                                   s_scm_truncate_quotient);
     }
   else if (SCM_REALP (x))
     {
@@ -2117,8 +2122,8 @@ SCM_PRIMITIVE_GENERIC (scm_truncate_quotient, "truncate-quotient", 2, 0, 0,
        return scm_i_inexact_truncate_quotient
          (SCM_REAL_VALUE (x), scm_to_double (y));
       else
-       SCM_WTA_DISPATCH_2 (g_scm_truncate_quotient, x, y, SCM_ARG2,
-                           s_scm_truncate_quotient);
+       return scm_wta_dispatch_2 (g_scm_truncate_quotient, x, y, SCM_ARG2,
+                                   s_scm_truncate_quotient);
     }
   else if (SCM_FRACTIONP (x))
     {
@@ -2128,12 +2133,12 @@ SCM_PRIMITIVE_GENERIC (scm_truncate_quotient, "truncate-quotient", 2, 0, 0,
       else if (SCM_I_INUMP (y) || SCM_BIGP (y) || SCM_FRACTIONP (y))
        return scm_i_exact_rational_truncate_quotient (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_truncate_quotient, x, y, SCM_ARG2,
-                           s_scm_truncate_quotient);
+       return scm_wta_dispatch_2 (g_scm_truncate_quotient, x, y, SCM_ARG2,
+                                   s_scm_truncate_quotient);
     }
   else
-    SCM_WTA_DISPATCH_2 (g_scm_truncate_quotient, x, y, SCM_ARG1,
-                       s_scm_truncate_quotient);
+    return scm_wta_dispatch_2 (g_scm_truncate_quotient, x, y, SCM_ARG1,
+                               s_scm_truncate_quotient);
 }
 #undef FUNC_NAME
 
@@ -2201,8 +2206,8 @@ SCM_PRIMITIVE_GENERIC (scm_truncate_remainder, "truncate-remainder", 2, 0, 0,
       else if (SCM_FRACTIONP (y))
        return scm_i_exact_rational_truncate_remainder (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_truncate_remainder, x, y, SCM_ARG2,
-                           s_scm_truncate_remainder);
+       return scm_wta_dispatch_2 (g_scm_truncate_remainder, x, y, SCM_ARG2,
+                                   s_scm_truncate_remainder);
     }
   else if (SCM_BIGP (x))
     {
@@ -2235,8 +2240,8 @@ SCM_PRIMITIVE_GENERIC (scm_truncate_remainder, "truncate-remainder", 2, 0, 0,
       else if (SCM_FRACTIONP (y))
        return scm_i_exact_rational_truncate_remainder (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_truncate_remainder, x, y, SCM_ARG2,
-                           s_scm_truncate_remainder);
+       return scm_wta_dispatch_2 (g_scm_truncate_remainder, x, y, SCM_ARG2,
+                                   s_scm_truncate_remainder);
     }
   else if (SCM_REALP (x))
     {
@@ -2245,8 +2250,8 @@ SCM_PRIMITIVE_GENERIC (scm_truncate_remainder, "truncate-remainder", 2, 0, 0,
        return scm_i_inexact_truncate_remainder
          (SCM_REAL_VALUE (x), scm_to_double (y));
       else
-       SCM_WTA_DISPATCH_2 (g_scm_truncate_remainder, x, y, SCM_ARG2,
-                           s_scm_truncate_remainder);
+       return scm_wta_dispatch_2 (g_scm_truncate_remainder, x, y, SCM_ARG2,
+                                   s_scm_truncate_remainder);
     }
   else if (SCM_FRACTIONP (x))
     {
@@ -2256,12 +2261,12 @@ SCM_PRIMITIVE_GENERIC (scm_truncate_remainder, "truncate-remainder", 2, 0, 0,
       else if (SCM_I_INUMP (y) || SCM_BIGP (y) || SCM_FRACTIONP (y))
        return scm_i_exact_rational_truncate_remainder (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_truncate_remainder, x, y, SCM_ARG2,
-                           s_scm_truncate_remainder);
+       return scm_wta_dispatch_2 (g_scm_truncate_remainder, x, y, SCM_ARG2,
+                                   s_scm_truncate_remainder);
     }
   else
-    SCM_WTA_DISPATCH_2 (g_scm_truncate_remainder, x, y, SCM_ARG1,
-                       s_scm_truncate_remainder);
+    return scm_wta_dispatch_2 (g_scm_truncate_remainder, x, y, SCM_ARG1,
+                               s_scm_truncate_remainder);
 }
 #undef FUNC_NAME
 
@@ -2548,8 +2553,8 @@ SCM_PRIMITIVE_GENERIC (scm_centered_quotient, "centered-quotient", 2, 0, 0,
       else if (SCM_FRACTIONP (y))
        return scm_i_exact_rational_centered_quotient (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_centered_quotient, x, y, SCM_ARG2,
-                           s_scm_centered_quotient);
+       return scm_wta_dispatch_2 (g_scm_centered_quotient, x, y, SCM_ARG2,
+                                   s_scm_centered_quotient);
     }
   else if (SCM_BIGP (x))
     {
@@ -2597,8 +2602,8 @@ SCM_PRIMITIVE_GENERIC (scm_centered_quotient, "centered-quotient", 2, 0, 0,
       else if (SCM_FRACTIONP (y))
        return scm_i_exact_rational_centered_quotient (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_centered_quotient, x, y, SCM_ARG2,
-                           s_scm_centered_quotient);
+       return scm_wta_dispatch_2 (g_scm_centered_quotient, x, y, SCM_ARG2,
+                                   s_scm_centered_quotient);
     }
   else if (SCM_REALP (x))
     {
@@ -2607,8 +2612,8 @@ SCM_PRIMITIVE_GENERIC (scm_centered_quotient, "centered-quotient", 2, 0, 0,
        return scm_i_inexact_centered_quotient
          (SCM_REAL_VALUE (x), scm_to_double (y));
       else
-       SCM_WTA_DISPATCH_2 (g_scm_centered_quotient, x, y, SCM_ARG2,
-                           s_scm_centered_quotient);
+       return scm_wta_dispatch_2 (g_scm_centered_quotient, x, y, SCM_ARG2,
+                                   s_scm_centered_quotient);
     }
   else if (SCM_FRACTIONP (x))
     {
@@ -2618,12 +2623,12 @@ SCM_PRIMITIVE_GENERIC (scm_centered_quotient, "centered-quotient", 2, 0, 0,
       else if (SCM_I_INUMP (y) || SCM_BIGP (y) || SCM_FRACTIONP (y))
        return scm_i_exact_rational_centered_quotient (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_centered_quotient, x, y, SCM_ARG2,
-                           s_scm_centered_quotient);
+       return scm_wta_dispatch_2 (g_scm_centered_quotient, x, y, SCM_ARG2,
+                                   s_scm_centered_quotient);
     }
   else
-    SCM_WTA_DISPATCH_2 (g_scm_centered_quotient, x, y, SCM_ARG1,
-                       s_scm_centered_quotient);
+    return scm_wta_dispatch_2 (g_scm_centered_quotient, x, y, SCM_ARG1,
+                               s_scm_centered_quotient);
 }
 #undef FUNC_NAME
 
@@ -2762,8 +2767,8 @@ SCM_PRIMITIVE_GENERIC (scm_centered_remainder, "centered-remainder", 2, 0, 0,
       else if (SCM_FRACTIONP (y))
        return scm_i_exact_rational_centered_remainder (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_centered_remainder, x, y, SCM_ARG2,
-                           s_scm_centered_remainder);
+       return scm_wta_dispatch_2 (g_scm_centered_remainder, x, y, SCM_ARG2,
+                                   s_scm_centered_remainder);
     }
   else if (SCM_BIGP (x))
     {
@@ -2803,8 +2808,8 @@ SCM_PRIMITIVE_GENERIC (scm_centered_remainder, "centered-remainder", 2, 0, 0,
       else if (SCM_FRACTIONP (y))
        return scm_i_exact_rational_centered_remainder (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_centered_remainder, x, y, SCM_ARG2,
-                           s_scm_centered_remainder);
+       return scm_wta_dispatch_2 (g_scm_centered_remainder, x, y, SCM_ARG2,
+                                   s_scm_centered_remainder);
     }
   else if (SCM_REALP (x))
     {
@@ -2813,8 +2818,8 @@ SCM_PRIMITIVE_GENERIC (scm_centered_remainder, "centered-remainder", 2, 0, 0,
        return scm_i_inexact_centered_remainder
          (SCM_REAL_VALUE (x), scm_to_double (y));
       else
-       SCM_WTA_DISPATCH_2 (g_scm_centered_remainder, x, y, SCM_ARG2,
-                           s_scm_centered_remainder);
+       return scm_wta_dispatch_2 (g_scm_centered_remainder, x, y, SCM_ARG2,
+                                   s_scm_centered_remainder);
     }
   else if (SCM_FRACTIONP (x))
     {
@@ -2824,12 +2829,12 @@ SCM_PRIMITIVE_GENERIC (scm_centered_remainder, "centered-remainder", 2, 0, 0,
       else if (SCM_I_INUMP (y) || SCM_BIGP (y) || SCM_FRACTIONP (y))
        return scm_i_exact_rational_centered_remainder (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_centered_remainder, x, y, SCM_ARG2,
-                           s_scm_centered_remainder);
+       return scm_wta_dispatch_2 (g_scm_centered_remainder, x, y, SCM_ARG2,
+                                   s_scm_centered_remainder);
     }
   else
-    SCM_WTA_DISPATCH_2 (g_scm_centered_remainder, x, y, SCM_ARG1,
-                       s_scm_centered_remainder);
+    return scm_wta_dispatch_2 (g_scm_centered_remainder, x, y, SCM_ARG1,
+                               s_scm_centered_remainder);
 }
 #undef FUNC_NAME
 
@@ -3244,8 +3249,8 @@ SCM_PRIMITIVE_GENERIC (scm_round_quotient, "round-quotient", 2, 0, 0,
       else if (SCM_FRACTIONP (y))
        return scm_i_exact_rational_round_quotient (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_round_quotient, x, y, SCM_ARG2,
-                           s_scm_round_quotient);
+       return scm_wta_dispatch_2 (g_scm_round_quotient, x, y, SCM_ARG2,
+                                   s_scm_round_quotient);
     }
   else if (SCM_BIGP (x))
     {
@@ -3295,8 +3300,8 @@ SCM_PRIMITIVE_GENERIC (scm_round_quotient, "round-quotient", 2, 0, 0,
       else if (SCM_FRACTIONP (y))
        return scm_i_exact_rational_round_quotient (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_round_quotient, x, y, SCM_ARG2,
-                           s_scm_round_quotient);
+       return scm_wta_dispatch_2 (g_scm_round_quotient, x, y, SCM_ARG2,
+                                   s_scm_round_quotient);
     }
   else if (SCM_REALP (x))
     {
@@ -3305,8 +3310,8 @@ SCM_PRIMITIVE_GENERIC (scm_round_quotient, "round-quotient", 2, 0, 0,
        return scm_i_inexact_round_quotient
          (SCM_REAL_VALUE (x), scm_to_double (y));
       else
-       SCM_WTA_DISPATCH_2 (g_scm_round_quotient, x, y, SCM_ARG2,
-                           s_scm_round_quotient);
+       return scm_wta_dispatch_2 (g_scm_round_quotient, x, y, SCM_ARG2,
+                                   s_scm_round_quotient);
     }
   else if (SCM_FRACTIONP (x))
     {
@@ -3316,12 +3321,12 @@ SCM_PRIMITIVE_GENERIC (scm_round_quotient, "round-quotient", 2, 0, 0,
       else if (SCM_I_INUMP (y) || SCM_BIGP (y) || SCM_FRACTIONP (y))
        return scm_i_exact_rational_round_quotient (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_round_quotient, x, y, SCM_ARG2,
-                           s_scm_round_quotient);
+       return scm_wta_dispatch_2 (g_scm_round_quotient, x, y, SCM_ARG2,
+                                   s_scm_round_quotient);
     }
   else
-    SCM_WTA_DISPATCH_2 (g_scm_round_quotient, x, y, SCM_ARG1,
-                       s_scm_round_quotient);
+    return scm_wta_dispatch_2 (g_scm_round_quotient, x, y, SCM_ARG1,
+                               s_scm_round_quotient);
 }
 #undef FUNC_NAME
 
@@ -3448,8 +3453,8 @@ SCM_PRIMITIVE_GENERIC (scm_round_remainder, "round-remainder", 2, 0, 0,
       else if (SCM_FRACTIONP (y))
        return scm_i_exact_rational_round_remainder (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_round_remainder, x, y, SCM_ARG2,
-                           s_scm_round_remainder);
+       return scm_wta_dispatch_2 (g_scm_round_remainder, x, y, SCM_ARG2,
+                                   s_scm_round_remainder);
     }
   else if (SCM_BIGP (x))
     {
@@ -3496,8 +3501,8 @@ SCM_PRIMITIVE_GENERIC (scm_round_remainder, "round-remainder", 2, 0, 0,
       else if (SCM_FRACTIONP (y))
        return scm_i_exact_rational_round_remainder (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_round_remainder, x, y, SCM_ARG2,
-                           s_scm_round_remainder);
+       return scm_wta_dispatch_2 (g_scm_round_remainder, x, y, SCM_ARG2,
+                                   s_scm_round_remainder);
     }
   else if (SCM_REALP (x))
     {
@@ -3506,8 +3511,8 @@ SCM_PRIMITIVE_GENERIC (scm_round_remainder, "round-remainder", 2, 0, 0,
        return scm_i_inexact_round_remainder
          (SCM_REAL_VALUE (x), scm_to_double (y));
       else
-       SCM_WTA_DISPATCH_2 (g_scm_round_remainder, x, y, SCM_ARG2,
-                           s_scm_round_remainder);
+       return scm_wta_dispatch_2 (g_scm_round_remainder, x, y, SCM_ARG2,
+                                   s_scm_round_remainder);
     }
   else if (SCM_FRACTIONP (x))
     {
@@ -3517,12 +3522,12 @@ SCM_PRIMITIVE_GENERIC (scm_round_remainder, "round-remainder", 2, 0, 0,
       else if (SCM_I_INUMP (y) || SCM_BIGP (y) || SCM_FRACTIONP (y))
        return scm_i_exact_rational_round_remainder (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_round_remainder, x, y, SCM_ARG2,
-                           s_scm_round_remainder);
+       return scm_wta_dispatch_2 (g_scm_round_remainder, x, y, SCM_ARG2,
+                                   s_scm_round_remainder);
     }
   else
-    SCM_WTA_DISPATCH_2 (g_scm_round_remainder, x, y, SCM_ARG1,
-                       s_scm_round_remainder);
+    return scm_wta_dispatch_2 (g_scm_round_remainder, x, y, SCM_ARG1,
+                               s_scm_round_remainder);
 }
 #undef FUNC_NAME
 
@@ -3906,7 +3911,7 @@ scm_gcd (SCM x, SCM y)
           goto big_inum;
         }
       else
-        SCM_WTA_DISPATCH_2 (g_gcd, x, y, SCM_ARG2, s_gcd);
+        return scm_wta_dispatch_2 (g_gcd, x, y, SCM_ARG2, s_gcd);
     }
   else if (SCM_BIGP (x))
     {
@@ -3936,10 +3941,10 @@ scm_gcd (SCM x, SCM y)
           return scm_i_normbig (result);
         }
       else
-        SCM_WTA_DISPATCH_2 (g_gcd, x, y, SCM_ARG2, s_gcd);
+        return scm_wta_dispatch_2 (g_gcd, x, y, SCM_ARG2, s_gcd);
     }
   else
-    SCM_WTA_DISPATCH_2 (g_gcd, x, y, SCM_ARG1, s_gcd);
+    return scm_wta_dispatch_2 (g_gcd, x, y, SCM_ARG1, s_gcd);
 }
 
 SCM_PRIMITIVE_GENERIC (scm_i_lcm, "lcm", 0, 2, 1,
@@ -3970,10 +3975,11 @@ scm_lcm (SCM n1, SCM n2)
       n2 = SCM_I_MAKINUM (1L);
     }
 
-  SCM_GASSERT2 (SCM_I_INUMP (n1) || SCM_BIGP (n1),
-                g_lcm, n1, n2, SCM_ARG1, s_lcm);
-  SCM_GASSERT2 (SCM_I_INUMP (n2) || SCM_BIGP (n2),
-                g_lcm, n1, n2, SCM_ARGn, s_lcm);
+  if (SCM_UNLIKELY (!(SCM_I_INUMP (n1) || SCM_BIGP (n1))))
+    return scm_wta_dispatch_2 (g_lcm, n1, n2, SCM_ARG1, s_lcm);
+  
+  if (SCM_UNLIKELY (!(SCM_I_INUMP (n2) || SCM_BIGP (n2))))
+    return scm_wta_dispatch_2 (g_lcm, n1, n2, SCM_ARG2, s_lcm);
 
   if (SCM_I_INUMP (n1))
     {
@@ -4106,7 +4112,7 @@ SCM scm_logand (SCM n1, SCM n2)
       else if SCM_BIGP (n2)
        {
        intbig: 
-         if (n1 == 0)
+         if (nn1 == 0)
            return SCM_INUM0;
          {
            SCM result_z = scm_i_mkbig ();
@@ -5103,12 +5109,6 @@ idbl2str (double f, char *a, int radix)
       exp++;
     }
  zero:
-#ifdef ENGNOT 
-  /* adding 9999 makes this equivalent to abs(x) % 3 */
-  dpt = (exp + 9999) % 3;
-  exp -= dpt++;
-  efmt = 1;
-#else
   efmt = (exp < -3) || (exp > wp + 2);
   if (!efmt)
     {
@@ -5125,7 +5125,6 @@ idbl2str (double f, char *a, int radix)
     }
   else
     dpt = 1;
-#endif
 
   do
     {
@@ -5147,7 +5146,6 @@ idbl2str (double f, char *a, int radix)
 
   if (dpt > 0)
     {
-#ifndef ENGNOT
       if ((dpt > 4) && (exp > 6))
        {
          d = (a[0] == '-' ? 2 : 1);
@@ -5157,7 +5155,6 @@ idbl2str (double f, char *a, int radix)
          efmt = 1;
        }
       else
-#endif
        {
          while (--dpt)
            a[ch++] = '0';
@@ -5664,7 +5661,7 @@ mem2decimal_from_point (SCM result, SCM mem,
          if (sign == 1)
            result = scm_product (result, e);
          else
-           result = scm_divide2real (result, e);
+           result = scm_divide (result, e);
 
          /* We've seen an exponent, thus the value is implicitly inexact. */
          x = INEXACT;
@@ -6180,7 +6177,8 @@ scm_num_eq_p (SCM x, SCM y)
       else if (SCM_FRACTIONP (y))
        return SCM_BOOL_F;
       else
-       SCM_WTA_DISPATCH_2 (g_scm_i_num_eq_p, x, y, SCM_ARGn, s_scm_i_num_eq_p);
+       return scm_wta_dispatch_2 (g_scm_i_num_eq_p, x, y, SCM_ARGn,
+                                   s_scm_i_num_eq_p);
     }
   else if (SCM_BIGP (x))
     {
@@ -6215,7 +6213,8 @@ scm_num_eq_p (SCM x, SCM y)
       else if (SCM_FRACTIONP (y))
        return SCM_BOOL_F;
       else
-       SCM_WTA_DISPATCH_2 (g_scm_i_num_eq_p, x, y, SCM_ARGn, s_scm_i_num_eq_p);
+       return scm_wta_dispatch_2 (g_scm_i_num_eq_p, x, y, SCM_ARGn,
+                                   s_scm_i_num_eq_p);
     }
   else if (SCM_REALP (x))
     {
@@ -6253,7 +6252,8 @@ scm_num_eq_p (SCM x, SCM y)
           goto again;
         }
       else
-       SCM_WTA_DISPATCH_2 (g_scm_i_num_eq_p, x, y, SCM_ARGn, s_scm_i_num_eq_p);
+       return scm_wta_dispatch_2 (g_scm_i_num_eq_p, x, y, SCM_ARGn,
+                                   s_scm_i_num_eq_p);
     }
   else if (SCM_COMPLEXP (x))
     {
@@ -6291,7 +6291,8 @@ scm_num_eq_p (SCM x, SCM y)
           goto again;
         }
       else
-       SCM_WTA_DISPATCH_2 (g_scm_i_num_eq_p, x, y, SCM_ARGn, s_scm_i_num_eq_p);
+       return scm_wta_dispatch_2 (g_scm_i_num_eq_p, x, y, SCM_ARGn,
+                                   s_scm_i_num_eq_p);
     }
   else if (SCM_FRACTIONP (x))
     {
@@ -6325,10 +6326,12 @@ scm_num_eq_p (SCM x, SCM y)
       else if (SCM_FRACTIONP (y))
        return scm_i_fraction_equalp (x, y);
       else
-       SCM_WTA_DISPATCH_2 (g_scm_i_num_eq_p, x, y, SCM_ARGn, s_scm_i_num_eq_p);
+       return scm_wta_dispatch_2 (g_scm_i_num_eq_p, x, y, SCM_ARGn,
+                                   s_scm_i_num_eq_p);
     }
   else
-    SCM_WTA_DISPATCH_2 (g_scm_i_num_eq_p, x, y, SCM_ARG1, s_scm_i_num_eq_p);
+    return scm_wta_dispatch_2 (g_scm_i_num_eq_p, x, y, SCM_ARG1,
+                               s_scm_i_num_eq_p);
 }
 
 
@@ -6387,7 +6390,8 @@ scm_less_p (SCM x, SCM y)
           goto again;
         }
       else
-       SCM_WTA_DISPATCH_2 (g_scm_i_num_less_p, x, y, SCM_ARGn, s_scm_i_num_less_p);
+       return scm_wta_dispatch_2 (g_scm_i_num_less_p, x, y, SCM_ARGn,
+                                   s_scm_i_num_less_p);
     }
   else if (SCM_BIGP (x))
     {
@@ -6415,7 +6419,8 @@ scm_less_p (SCM x, SCM y)
       else if (SCM_FRACTIONP (y))
         goto int_frac;
       else
-       SCM_WTA_DISPATCH_2 (g_scm_i_num_less_p, x, y, SCM_ARGn, s_scm_i_num_less_p);
+       return scm_wta_dispatch_2 (g_scm_i_num_less_p, x, y, SCM_ARGn,
+                                   s_scm_i_num_less_p);
     }
   else if (SCM_REALP (x))
     {
@@ -6443,7 +6448,8 @@ scm_less_p (SCM x, SCM y)
           goto again;
         }
       else
-       SCM_WTA_DISPATCH_2 (g_scm_i_num_less_p, x, y, SCM_ARGn, s_scm_i_num_less_p);
+       return scm_wta_dispatch_2 (g_scm_i_num_less_p, x, y, SCM_ARGn,
+                                   s_scm_i_num_less_p);
     }
   else if (SCM_FRACTIONP (x))
     {
@@ -6476,10 +6482,12 @@ scm_less_p (SCM x, SCM y)
           goto again;
         }
       else
-       SCM_WTA_DISPATCH_2 (g_scm_i_num_less_p, x, y, SCM_ARGn, s_scm_i_num_less_p);
+       return scm_wta_dispatch_2 (g_scm_i_num_less_p, x, y, SCM_ARGn,
+                                   s_scm_i_num_less_p);
     }
   else
-    SCM_WTA_DISPATCH_2 (g_scm_i_num_less_p, x, y, SCM_ARG1, s_scm_i_num_less_p);
+    return scm_wta_dispatch_2 (g_scm_i_num_less_p, x, y, SCM_ARG1,
+                               s_scm_i_num_less_p);
 }
 
 
@@ -6508,9 +6516,9 @@ SCM
 scm_gr_p (SCM x, SCM y)
 {
   if (!SCM_NUMBERP (x))
-    SCM_WTA_DISPATCH_2 (g_scm_i_num_gr_p, x, y, SCM_ARG1, FUNC_NAME);
+    return scm_wta_dispatch_2 (g_scm_i_num_gr_p, x, y, SCM_ARG1, FUNC_NAME);
   else if (!SCM_NUMBERP (y))
-    SCM_WTA_DISPATCH_2 (g_scm_i_num_gr_p, x, y, SCM_ARG2, FUNC_NAME);
+    return scm_wta_dispatch_2 (g_scm_i_num_gr_p, x, y, SCM_ARG2, FUNC_NAME);
   else
     return scm_less_p (y, x);
 }
@@ -6542,9 +6550,9 @@ SCM
 scm_leq_p (SCM x, SCM y)
 {
   if (!SCM_NUMBERP (x))
-    SCM_WTA_DISPATCH_2 (g_scm_i_num_leq_p, x, y, SCM_ARG1, FUNC_NAME);
+    return scm_wta_dispatch_2 (g_scm_i_num_leq_p, x, y, SCM_ARG1, FUNC_NAME);
   else if (!SCM_NUMBERP (y))
-    SCM_WTA_DISPATCH_2 (g_scm_i_num_leq_p, x, y, SCM_ARG2, FUNC_NAME);
+    return scm_wta_dispatch_2 (g_scm_i_num_leq_p, x, y, SCM_ARG2, FUNC_NAME);
   else if (scm_is_true (scm_nan_p (x)) || scm_is_true (scm_nan_p (y)))
     return SCM_BOOL_F;
   else
@@ -6578,9 +6586,9 @@ SCM
 scm_geq_p (SCM x, SCM y)
 {
   if (!SCM_NUMBERP (x))
-    SCM_WTA_DISPATCH_2 (g_scm_i_num_geq_p, x, y, SCM_ARG1, FUNC_NAME);
+    return scm_wta_dispatch_2 (g_scm_i_num_geq_p, x, y, SCM_ARG1, FUNC_NAME);
   else if (!SCM_NUMBERP (y))
-    SCM_WTA_DISPATCH_2 (g_scm_i_num_geq_p, x, y, SCM_ARG2, FUNC_NAME);
+    return scm_wta_dispatch_2 (g_scm_i_num_geq_p, x, y, SCM_ARG2, FUNC_NAME);
   else if (scm_is_true (scm_nan_p (x)) || scm_is_true (scm_nan_p (y)))
     return SCM_BOOL_F;
   else
@@ -6607,7 +6615,7 @@ SCM_PRIMITIVE_GENERIC (scm_zero_p, "zero?", 1, 0, 0,
   else if (SCM_FRACTIONP (z))
     return SCM_BOOL_F;
   else
-    SCM_WTA_DISPATCH_1 (g_scm_zero_p, z, SCM_ARG1, s_scm_zero_p);
+    return scm_wta_dispatch_1 (g_scm_zero_p, z, SCM_ARG1, s_scm_zero_p);
 }
 #undef FUNC_NAME
 
@@ -6631,7 +6639,7 @@ SCM_PRIMITIVE_GENERIC (scm_positive_p, "positive?", 1, 0, 0,
   else if (SCM_FRACTIONP (x))
     return scm_positive_p (SCM_FRACTION_NUMERATOR (x));
   else
-    SCM_WTA_DISPATCH_1 (g_scm_positive_p, x, SCM_ARG1, s_scm_positive_p);
+    return scm_wta_dispatch_1 (g_scm_positive_p, x, SCM_ARG1, s_scm_positive_p);
 }
 #undef FUNC_NAME
 
@@ -6655,7 +6663,7 @@ SCM_PRIMITIVE_GENERIC (scm_negative_p, "negative?", 1, 0, 0,
   else if (SCM_FRACTIONP (x))
     return scm_negative_p (SCM_FRACTION_NUMERATOR (x));
   else
-    SCM_WTA_DISPATCH_1 (g_scm_negative_p, x, SCM_ARG1, s_scm_negative_p);
+    return scm_wta_dispatch_1 (g_scm_negative_p, x, SCM_ARG1, s_scm_negative_p);
 }
 #undef FUNC_NAME
 
@@ -6689,11 +6697,11 @@ scm_max (SCM x, SCM y)
   if (SCM_UNBNDP (y))
     {
       if (SCM_UNBNDP (x))
-       SCM_WTA_DISPATCH_0 (g_max, s_max);
+       return scm_wta_dispatch_0 (g_max, s_max);
       else if (SCM_I_INUMP(x) || SCM_BIGP(x) || SCM_REALP(x) || SCM_FRACTIONP(x))
        return x;
       else
-       SCM_WTA_DISPATCH_1 (g_max, x, SCM_ARG1, s_max);
+       return scm_wta_dispatch_1 (g_max, x, SCM_ARG1, s_max);
     }
   
   if (SCM_I_INUMP (x))
@@ -6732,7 +6740,7 @@ scm_max (SCM x, SCM y)
           return (scm_is_false (scm_less_p (x, y)) ? x : y);
        }
       else
-       SCM_WTA_DISPATCH_2 (g_max, x, y, SCM_ARGn, s_max);
+       return scm_wta_dispatch_2 (g_max, x, y, SCM_ARGn, s_max);
     }
   else if (SCM_BIGP (x))
     {
@@ -6762,7 +6770,7 @@ scm_max (SCM x, SCM y)
           goto use_less;
        }
       else
-       SCM_WTA_DISPATCH_2 (g_max, x, y, SCM_ARGn, s_max);
+       return scm_wta_dispatch_2 (g_max, x, y, SCM_ARGn, s_max);
     }
   else if (SCM_REALP (x))
     {
@@ -6817,7 +6825,7 @@ scm_max (SCM x, SCM y)
          return (xx < yy) ? scm_from_double (yy) : x;
        }
       else
-       SCM_WTA_DISPATCH_2 (g_max, x, y, SCM_ARGn, s_max);
+       return scm_wta_dispatch_2 (g_max, x, y, SCM_ARGn, s_max);
     }
   else if (SCM_FRACTIONP (x))
     {
@@ -6840,10 +6848,10 @@ scm_max (SCM x, SCM y)
           goto use_less;
        }
       else
-       SCM_WTA_DISPATCH_2 (g_max, x, y, SCM_ARGn, s_max);
+       return scm_wta_dispatch_2 (g_max, x, y, SCM_ARGn, s_max);
     }
   else
-    SCM_WTA_DISPATCH_2 (g_max, x, y, SCM_ARG1, s_max);
+    return scm_wta_dispatch_2 (g_max, x, y, SCM_ARG1, s_max);
 }
 
 
@@ -6870,11 +6878,11 @@ scm_min (SCM x, SCM y)
   if (SCM_UNBNDP (y))
     {
       if (SCM_UNBNDP (x))
-       SCM_WTA_DISPATCH_0 (g_min, s_min);
+       return scm_wta_dispatch_0 (g_min, s_min);
       else if (SCM_I_INUMP(x) || SCM_BIGP(x) || SCM_REALP(x) || SCM_FRACTIONP(x))
        return x;
       else
-       SCM_WTA_DISPATCH_1 (g_min, x, SCM_ARG1, s_min);
+       return scm_wta_dispatch_1 (g_min, x, SCM_ARG1, s_min);
     }
   
   if (SCM_I_INUMP (x))
@@ -6903,7 +6911,7 @@ scm_min (SCM x, SCM y)
           return (scm_is_false (scm_less_p (x, y)) ? y : x);
        }
       else
-       SCM_WTA_DISPATCH_2 (g_min, x, y, SCM_ARGn, s_min);
+       return scm_wta_dispatch_2 (g_min, x, y, SCM_ARGn, s_min);
     }
   else if (SCM_BIGP (x))
     {
@@ -6933,7 +6941,7 @@ scm_min (SCM x, SCM y)
           goto use_less;
        }
       else
-       SCM_WTA_DISPATCH_2 (g_min, x, y, SCM_ARGn, s_min);
+       return scm_wta_dispatch_2 (g_min, x, y, SCM_ARGn, s_min);
     }
   else if (SCM_REALP (x))
     {
@@ -6977,7 +6985,7 @@ scm_min (SCM x, SCM y)
          return (yy < xx) ? scm_from_double (yy) : x;
        }
       else
-       SCM_WTA_DISPATCH_2 (g_min, x, y, SCM_ARGn, s_min);
+       return scm_wta_dispatch_2 (g_min, x, y, SCM_ARGn, s_min);
     }
   else if (SCM_FRACTIONP (x))
     {
@@ -7000,10 +7008,10 @@ scm_min (SCM x, SCM y)
           goto use_less;
        }
       else
-       SCM_WTA_DISPATCH_2 (g_min, x, y, SCM_ARGn, s_min);
+       return scm_wta_dispatch_2 (g_min, x, y, SCM_ARGn, s_min);
     }
   else
-    SCM_WTA_DISPATCH_2 (g_min, x, y, SCM_ARG1, s_min);
+    return scm_wta_dispatch_2 (g_min, x, y, SCM_ARG1, s_min);
 }
 
 
@@ -7032,7 +7040,7 @@ scm_sum (SCM x, SCM y)
     {
       if (SCM_NUMBERP (x)) return x;
       if (SCM_UNBNDP (x)) return SCM_INUM0;
-      SCM_WTA_DISPATCH_1 (g_sum, x, SCM_ARG1, s_sum);
+      return scm_wta_dispatch_1 (g_sum, x, SCM_ARG1, s_sum);
     }
 
   if (SCM_LIKELY (SCM_I_INUMP (x)))
@@ -7065,7 +7073,7 @@ scm_sum (SCM x, SCM y)
                                        scm_product (x, SCM_FRACTION_DENOMINATOR (y))),
                               SCM_FRACTION_DENOMINATOR (y));
       else
-        SCM_WTA_DISPATCH_2 (g_sum, x, y, SCM_ARGn, s_sum);
+        return scm_wta_dispatch_2 (g_sum, x, y, SCM_ARGn, s_sum);
     } else if (SCM_BIGP (x))
       {
        if (SCM_I_INUMP (y))
@@ -7130,7 +7138,7 @@ scm_sum (SCM x, SCM y)
                                          scm_product (x, SCM_FRACTION_DENOMINATOR (y))),
                                 SCM_FRACTION_DENOMINATOR (y));
        else
-         SCM_WTA_DISPATCH_2 (g_sum, x, y, SCM_ARGn, s_sum);
+         return scm_wta_dispatch_2 (g_sum, x, y, SCM_ARGn, s_sum);
       }
   else if (SCM_REALP (x))
     {
@@ -7150,7 +7158,7 @@ scm_sum (SCM x, SCM y)
       else if (SCM_FRACTIONP (y))
        return scm_from_double (SCM_REAL_VALUE (x) + scm_i_fraction2double (y));
       else
-       SCM_WTA_DISPATCH_2 (g_sum, x, y, SCM_ARGn, s_sum);
+       return scm_wta_dispatch_2 (g_sum, x, y, SCM_ARGn, s_sum);
     }
   else if (SCM_COMPLEXP (x))
     {
@@ -7174,7 +7182,7 @@ scm_sum (SCM x, SCM y)
        return scm_c_make_rectangular (SCM_COMPLEX_REAL (x) + scm_i_fraction2double (y),
                                 SCM_COMPLEX_IMAG (x));
       else
-       SCM_WTA_DISPATCH_2 (g_sum, x, y, SCM_ARGn, s_sum);
+       return scm_wta_dispatch_2 (g_sum, x, y, SCM_ARGn, s_sum);
     }
   else if (SCM_FRACTIONP (x))
     {
@@ -7197,10 +7205,10 @@ scm_sum (SCM x, SCM y)
                                        scm_product (SCM_FRACTION_NUMERATOR (y), SCM_FRACTION_DENOMINATOR (x))),
                               scm_product (SCM_FRACTION_DENOMINATOR (x), SCM_FRACTION_DENOMINATOR (y)));
       else
-       SCM_WTA_DISPATCH_2 (g_sum, x, y, SCM_ARGn, s_sum);
+       return scm_wta_dispatch_2 (g_sum, x, y, SCM_ARGn, s_sum);
     }
   else
-    SCM_WTA_DISPATCH_2 (g_sum, x, y, SCM_ARG1, s_sum);
+    return scm_wta_dispatch_2 (g_sum, x, y, SCM_ARG1, s_sum);
 }
 
 
@@ -7240,7 +7248,7 @@ scm_difference (SCM x, SCM y)
   if (SCM_UNLIKELY (SCM_UNBNDP (y)))
     {
       if (SCM_UNBNDP (x))
-        SCM_WTA_DISPATCH_0 (g_difference, s_difference);
+        return scm_wta_dispatch_0 (g_difference, s_difference);
       else 
         if (SCM_I_INUMP (x))
           {
@@ -7263,7 +7271,7 @@ scm_difference (SCM x, SCM y)
          return scm_i_make_ratio (scm_difference (SCM_FRACTION_NUMERATOR (x), SCM_UNDEFINED),
                                 SCM_FRACTION_DENOMINATOR (x));
         else
-          SCM_WTA_DISPATCH_1 (g_difference, x, SCM_ARG1, s_difference);
+          return scm_wta_dispatch_1 (g_difference, x, SCM_ARG1, s_difference);
     }
   
   if (SCM_LIKELY (SCM_I_INUMP (x)))
@@ -7350,7 +7358,7 @@ scm_difference (SCM x, SCM y)
                                               SCM_FRACTION_NUMERATOR (y)),
                               SCM_FRACTION_DENOMINATOR (y));
       else
-       SCM_WTA_DISPATCH_2 (g_difference, x, y, SCM_ARGn, s_difference);
+       return scm_wta_dispatch_2 (g_difference, x, y, SCM_ARGn, s_difference);
     }
   else if (SCM_BIGP (x))
     {
@@ -7414,7 +7422,8 @@ scm_difference (SCM x, SCM y)
        return scm_i_make_ratio (scm_difference (scm_product (x, SCM_FRACTION_DENOMINATOR (y)),
                                               SCM_FRACTION_NUMERATOR (y)),
                               SCM_FRACTION_DENOMINATOR (y));
-      else SCM_WTA_DISPATCH_2 (g_difference, x, y, SCM_ARGn, s_difference);
+      else
+        return scm_wta_dispatch_2 (g_difference, x, y, SCM_ARGn, s_difference);
     }
   else if (SCM_REALP (x))
     {
@@ -7434,7 +7443,7 @@ scm_difference (SCM x, SCM y)
       else if (SCM_FRACTIONP (y))
        return scm_from_double (SCM_REAL_VALUE (x) - scm_i_fraction2double (y));
       else
-       SCM_WTA_DISPATCH_2 (g_difference, x, y, SCM_ARGn, s_difference);
+       return scm_wta_dispatch_2 (g_difference, x, y, SCM_ARGn, s_difference);
     }
   else if (SCM_COMPLEXP (x))
     {
@@ -7458,7 +7467,7 @@ scm_difference (SCM x, SCM y)
        return scm_c_make_rectangular (SCM_COMPLEX_REAL (x) - scm_i_fraction2double (y),
                                 SCM_COMPLEX_IMAG (x));
       else
-       SCM_WTA_DISPATCH_2 (g_difference, x, y, SCM_ARGn, s_difference);
+       return scm_wta_dispatch_2 (g_difference, x, y, SCM_ARGn, s_difference);
     }
   else if (SCM_FRACTIONP (x))
     {
@@ -7482,10 +7491,10 @@ scm_difference (SCM x, SCM y)
                                               scm_product (SCM_FRACTION_NUMERATOR (y), SCM_FRACTION_DENOMINATOR (x))),
                               scm_product (SCM_FRACTION_DENOMINATOR (x), SCM_FRACTION_DENOMINATOR (y)));
       else
-       SCM_WTA_DISPATCH_2 (g_difference, x, y, SCM_ARGn, s_difference);
+       return scm_wta_dispatch_2 (g_difference, x, y, SCM_ARGn, s_difference);
     }
   else
-    SCM_WTA_DISPATCH_2 (g_difference, x, y, SCM_ARG1, s_difference);
+    return scm_wta_dispatch_2 (g_difference, x, y, SCM_ARG1, s_difference);
 }
 #undef FUNC_NAME
 
@@ -7528,7 +7537,7 @@ scm_product (SCM x, SCM y)
       else if (SCM_NUMBERP (x))
        return x;
       else
-       SCM_WTA_DISPATCH_1 (g_product, x, SCM_ARG1, s_product);
+       return scm_wta_dispatch_1 (g_product, x, SCM_ARG1, s_product);
     }
   
   if (SCM_LIKELY (SCM_I_INUMP (x)))
@@ -7561,7 +7570,7 @@ scm_product (SCM x, SCM y)
          else if (SCM_NUMP (y))
            return SCM_INUM0;
          else
-           SCM_WTA_DISPATCH_2 (g_product, x, y, SCM_ARGn, s_product);
+           return scm_wta_dispatch_2 (g_product, x, y, SCM_ARGn, s_product);
          break;
         case -1:
          /*
@@ -7606,7 +7615,7 @@ scm_product (SCM x, SCM y)
        return scm_i_make_ratio (scm_product (x, SCM_FRACTION_NUMERATOR (y)),
                               SCM_FRACTION_DENOMINATOR (y));
       else
-       SCM_WTA_DISPATCH_2 (g_product, x, y, SCM_ARGn, s_product);
+       return scm_wta_dispatch_2 (g_product, x, y, SCM_ARGn, s_product);
     }
   else if (SCM_BIGP (x))
     {
@@ -7641,7 +7650,7 @@ scm_product (SCM x, SCM y)
        return scm_i_make_ratio (scm_product (x, SCM_FRACTION_NUMERATOR (y)),
                               SCM_FRACTION_DENOMINATOR (y));
       else
-       SCM_WTA_DISPATCH_2 (g_product, x, y, SCM_ARGn, s_product);
+       return scm_wta_dispatch_2 (g_product, x, y, SCM_ARGn, s_product);
     }
   else if (SCM_REALP (x))
     {
@@ -7664,7 +7673,7 @@ scm_product (SCM x, SCM y)
       else if (SCM_FRACTIONP (y))
        return scm_from_double (SCM_REAL_VALUE (x) * scm_i_fraction2double (y));
       else
-       SCM_WTA_DISPATCH_2 (g_product, x, y, SCM_ARGn, s_product);
+       return scm_wta_dispatch_2 (g_product, x, y, SCM_ARGn, s_product);
     }
   else if (SCM_COMPLEXP (x))
     {
@@ -7697,7 +7706,7 @@ scm_product (SCM x, SCM y)
                                   yy * SCM_COMPLEX_IMAG (x));
        }
       else
-       SCM_WTA_DISPATCH_2 (g_product, x, y, SCM_ARGn, s_product);
+       return scm_wta_dispatch_2 (g_product, x, y, SCM_ARGn, s_product);
     }
   else if (SCM_FRACTIONP (x))
     {
@@ -7722,10 +7731,10 @@ scm_product (SCM x, SCM y)
                               scm_product (SCM_FRACTION_DENOMINATOR (x),
                                            SCM_FRACTION_DENOMINATOR (y)));
       else
-       SCM_WTA_DISPATCH_2 (g_product, x, y, SCM_ARGn, s_product);
+       return scm_wta_dispatch_2 (g_product, x, y, SCM_ARGn, s_product);
     }
   else
-    SCM_WTA_DISPATCH_2 (g_product, x, y, SCM_ARG1, s_product);
+    return scm_wta_dispatch_2 (g_product, x, y, SCM_ARG1, s_product);
 }
 
 #if ((defined (HAVE_ISINF) && defined (HAVE_ISNAN)) \
@@ -7789,7 +7798,7 @@ do_divide (SCM x, SCM y, int inexact)
   if (SCM_UNLIKELY (SCM_UNBNDP (y)))
     {
       if (SCM_UNBNDP (x))
-       SCM_WTA_DISPATCH_0 (g_divide, s_divide);
+       return scm_wta_dispatch_0 (g_divide, s_divide);
       else if (SCM_I_INUMP (x))
        {
          scm_t_inum xx = SCM_I_INUM (x);
@@ -7843,7 +7852,7 @@ do_divide (SCM x, SCM y, int inexact)
        return scm_i_make_ratio (SCM_FRACTION_DENOMINATOR (x),
                               SCM_FRACTION_NUMERATOR (x));
       else
-       SCM_WTA_DISPATCH_1 (g_divide, x, SCM_ARG1, s_divide);
+       return scm_wta_dispatch_1 (g_divide, x, SCM_ARG1, s_divide);
     }
 
   if (SCM_LIKELY (SCM_I_INUMP (x)))
@@ -7917,7 +7926,7 @@ do_divide (SCM x, SCM y, int inexact)
        return scm_i_make_ratio (scm_product (x, SCM_FRACTION_DENOMINATOR (y)),
                               SCM_FRACTION_NUMERATOR (y));
       else
-       SCM_WTA_DISPATCH_2 (g_divide, x, y, SCM_ARGn, s_divide);
+       return scm_wta_dispatch_2 (g_divide, x, y, SCM_ARGn, s_divide);
     }
   else if (SCM_BIGP (x))
     {
@@ -8016,7 +8025,7 @@ do_divide (SCM x, SCM y, int inexact)
        return scm_i_make_ratio (scm_product (x, SCM_FRACTION_DENOMINATOR (y)),
                               SCM_FRACTION_NUMERATOR (y));
       else
-       SCM_WTA_DISPATCH_2 (g_divide, x, y, SCM_ARGn, s_divide);
+       return scm_wta_dispatch_2 (g_divide, x, y, SCM_ARGn, s_divide);
     }
   else if (SCM_REALP (x))
     {
@@ -8055,7 +8064,7 @@ do_divide (SCM x, SCM y, int inexact)
       else if (SCM_FRACTIONP (y))
        return scm_from_double (rx / scm_i_fraction2double (y));
       else
-       SCM_WTA_DISPATCH_2 (g_divide, x, y, SCM_ARGn, s_divide);
+       return scm_wta_dispatch_2 (g_divide, x, y, SCM_ARGn, s_divide);
     }
   else if (SCM_COMPLEXP (x))
     {
@@ -8113,7 +8122,7 @@ do_divide (SCM x, SCM y, int inexact)
          return scm_c_make_rectangular (rx / yy, ix / yy);
        }
       else
-       SCM_WTA_DISPATCH_2 (g_divide, x, y, SCM_ARGn, s_divide);
+       return scm_wta_dispatch_2 (g_divide, x, y, SCM_ARGn, s_divide);
     }
   else if (SCM_FRACTIONP (x))
     {
@@ -8152,10 +8161,10 @@ do_divide (SCM x, SCM y, int inexact)
        return scm_i_make_ratio (scm_product (SCM_FRACTION_NUMERATOR (x), SCM_FRACTION_DENOMINATOR (y)),
                               scm_product (SCM_FRACTION_NUMERATOR (y), SCM_FRACTION_DENOMINATOR (x)));
       else 
-       SCM_WTA_DISPATCH_2 (g_divide, x, y, SCM_ARGn, s_divide);
+       return scm_wta_dispatch_2 (g_divide, x, y, SCM_ARGn, s_divide);
     }
   else
-    SCM_WTA_DISPATCH_2 (g_divide, x, y, SCM_ARG1, s_divide);
+    return scm_wta_dispatch_2 (g_divide, x, y, SCM_ARG1, s_divide);
 }
 
 SCM
@@ -8232,7 +8241,7 @@ SCM_PRIMITIVE_GENERIC (scm_truncate_number, "truncate", 1, 0, 0,
     return scm_truncate_quotient (SCM_FRACTION_NUMERATOR (x),
                                  SCM_FRACTION_DENOMINATOR (x));
   else
-    SCM_WTA_DISPATCH_1 (g_scm_truncate_number, x, SCM_ARG1,
+    return scm_wta_dispatch_1 (g_scm_truncate_number, x, SCM_ARG1,
                        s_scm_truncate_number);
 }
 #undef FUNC_NAME
@@ -8252,8 +8261,8 @@ SCM_PRIMITIVE_GENERIC (scm_round_number, "round", 1, 0, 0,
     return scm_round_quotient (SCM_FRACTION_NUMERATOR (x),
                               SCM_FRACTION_DENOMINATOR (x));
   else
-    SCM_WTA_DISPATCH_1 (g_scm_round_number, x, SCM_ARG1,
-                       s_scm_round_number);
+    return scm_wta_dispatch_1 (g_scm_round_number, x, SCM_ARG1,
+                               s_scm_round_number);
 }
 #undef FUNC_NAME
 
@@ -8270,7 +8279,7 @@ SCM_PRIMITIVE_GENERIC (scm_floor, "floor", 1, 0, 0,
     return scm_floor_quotient (SCM_FRACTION_NUMERATOR (x),
                               SCM_FRACTION_DENOMINATOR (x));
   else
-    SCM_WTA_DISPATCH_1 (g_scm_floor, x, 1, s_scm_floor);
+    return scm_wta_dispatch_1 (g_scm_floor, x, 1, s_scm_floor);
 }  
 #undef FUNC_NAME
 
@@ -8287,7 +8296,7 @@ SCM_PRIMITIVE_GENERIC (scm_ceiling, "ceiling", 1, 0, 0,
     return scm_ceiling_quotient (SCM_FRACTION_NUMERATOR (x),
                                 SCM_FRACTION_DENOMINATOR (x));
   else
-    SCM_WTA_DISPATCH_1 (g_scm_ceiling, x, 1, s_scm_ceiling);
+    return scm_wta_dispatch_1 (g_scm_ceiling, x, 1, s_scm_ceiling);
 }
 #undef FUNC_NAME
 
@@ -8326,9 +8335,9 @@ SCM_PRIMITIVE_GENERIC (scm_expt, "expt", 2, 0, 0,
   else if (scm_is_complex (x) && scm_is_complex (y))
     return scm_exp (scm_product (scm_log (x), y));
   else if (scm_is_complex (x))
-    SCM_WTA_DISPATCH_2 (g_scm_expt, x, y, SCM_ARG2, s_scm_expt);
+    return scm_wta_dispatch_2 (g_scm_expt, x, y, SCM_ARG2, s_scm_expt);
   else
-    SCM_WTA_DISPATCH_2 (g_scm_expt, x, y, SCM_ARG1, s_scm_expt);
+    return scm_wta_dispatch_2 (g_scm_expt, x, y, SCM_ARG1, s_scm_expt);
 }
 #undef FUNC_NAME
 
@@ -8355,7 +8364,7 @@ SCM_PRIMITIVE_GENERIC (scm_sin, "sin", 1, 0, 0,
                                      cos (x) * sinh (y));
     }
   else
-    SCM_WTA_DISPATCH_1 (g_scm_sin, z, 1, s_scm_sin);
+    return scm_wta_dispatch_1 (g_scm_sin, z, 1, s_scm_sin);
 }
 #undef FUNC_NAME
 
@@ -8376,7 +8385,7 @@ SCM_PRIMITIVE_GENERIC (scm_cos, "cos", 1, 0, 0,
                                      -sin (x) * sinh (y));
     }
   else
-    SCM_WTA_DISPATCH_1 (g_scm_cos, z, 1, s_scm_cos);
+    return scm_wta_dispatch_1 (g_scm_cos, z, 1, s_scm_cos);
 }
 #undef FUNC_NAME
 
@@ -8401,7 +8410,7 @@ SCM_PRIMITIVE_GENERIC (scm_tan, "tan", 1, 0, 0,
       return scm_c_make_rectangular (sin (x) / w, sinh (y) / w);
     }
   else
-    SCM_WTA_DISPATCH_1 (g_scm_tan, z, 1, s_scm_tan);
+    return scm_wta_dispatch_1 (g_scm_tan, z, 1, s_scm_tan);
 }
 #undef FUNC_NAME
 
@@ -8422,7 +8431,7 @@ SCM_PRIMITIVE_GENERIC (scm_sinh, "sinh", 1, 0, 0,
                                      cosh (x) * sin (y));
     }
   else
-    SCM_WTA_DISPATCH_1 (g_scm_sinh, z, 1, s_scm_sinh);
+    return scm_wta_dispatch_1 (g_scm_sinh, z, 1, s_scm_sinh);
 }
 #undef FUNC_NAME
 
@@ -8443,7 +8452,7 @@ SCM_PRIMITIVE_GENERIC (scm_cosh, "cosh", 1, 0, 0,
                                      sinh (x) * sin (y));
     }
   else
-    SCM_WTA_DISPATCH_1 (g_scm_cosh, z, 1, s_scm_cosh);
+    return scm_wta_dispatch_1 (g_scm_cosh, z, 1, s_scm_cosh);
 }
 #undef FUNC_NAME
 
@@ -8468,7 +8477,7 @@ SCM_PRIMITIVE_GENERIC (scm_tanh, "tanh", 1, 0, 0,
       return scm_c_make_rectangular (sinh (x) / w, sin (y) / w);
     }
   else
-    SCM_WTA_DISPATCH_1 (g_scm_tanh, z, 1, s_scm_tanh);
+    return scm_wta_dispatch_1 (g_scm_tanh, z, 1, s_scm_tanh);
 }
 #undef FUNC_NAME
 
@@ -8496,7 +8505,7 @@ SCM_PRIMITIVE_GENERIC (scm_asin, "asin", 1, 0, 0,
                           scm_sys_asinh (scm_c_make_rectangular (-y, x)));
     }
   else
-    SCM_WTA_DISPATCH_1 (g_scm_asin, z, 1, s_scm_asin);
+    return scm_wta_dispatch_1 (g_scm_asin, z, 1, s_scm_asin);
 }
 #undef FUNC_NAME
 
@@ -8526,7 +8535,7 @@ SCM_PRIMITIVE_GENERIC (scm_acos, "acos", 1, 0, 0,
                                    scm_sys_asinh (scm_c_make_rectangular (-y, x))));
     }
   else
-    SCM_WTA_DISPATCH_1 (g_scm_acos, z, 1, s_scm_acos);
+    return scm_wta_dispatch_1 (g_scm_acos, z, 1, s_scm_acos);
 }
 #undef FUNC_NAME
 
@@ -8553,17 +8562,17 @@ SCM_PRIMITIVE_GENERIC (scm_atan, "atan", 1, 1, 0,
                              scm_c_make_rectangular (0, 2));
         }
       else
-        SCM_WTA_DISPATCH_1 (g_scm_atan, z, SCM_ARG1, s_scm_atan);
+        return scm_wta_dispatch_1 (g_scm_atan, z, SCM_ARG1, s_scm_atan);
     }
   else if (scm_is_real (z))
     {
       if (scm_is_real (y))
         return scm_from_double (atan2 (scm_to_double (z), scm_to_double (y)));
       else
-        SCM_WTA_DISPATCH_2 (g_scm_atan, z, y, SCM_ARG2, s_scm_atan);
+        return scm_wta_dispatch_2 (g_scm_atan, z, y, SCM_ARG2, s_scm_atan);
     }
   else
-    SCM_WTA_DISPATCH_2 (g_scm_atan, z, y, SCM_ARG1, s_scm_atan);
+    return scm_wta_dispatch_2 (g_scm_atan, z, y, SCM_ARG1, s_scm_atan);
 }
 #undef FUNC_NAME
 
@@ -8581,7 +8590,7 @@ SCM_PRIMITIVE_GENERIC (scm_sys_asinh, "asinh", 1, 0, 0,
                              scm_sqrt (scm_sum (scm_product (z, z),
                                                 SCM_INUM1))));
   else
-    SCM_WTA_DISPATCH_1 (g_scm_sys_asinh, z, 1, s_scm_sys_asinh);
+    return scm_wta_dispatch_1 (g_scm_sys_asinh, z, 1, s_scm_sys_asinh);
 }
 #undef FUNC_NAME
 
@@ -8599,7 +8608,7 @@ SCM_PRIMITIVE_GENERIC (scm_sys_acosh, "acosh", 1, 0, 0,
                              scm_sqrt (scm_difference (scm_product (z, z),
                                                        SCM_INUM1))));
   else
-    SCM_WTA_DISPATCH_1 (g_scm_sys_acosh, z, 1, s_scm_sys_acosh);
+    return scm_wta_dispatch_1 (g_scm_sys_acosh, z, 1, s_scm_sys_acosh);
 }
 #undef FUNC_NAME
 
@@ -8617,7 +8626,7 @@ SCM_PRIMITIVE_GENERIC (scm_sys_atanh, "atanh", 1, 0, 0,
                                             scm_difference (SCM_INUM1, z))),
                        SCM_I_MAKINUM (2));
   else
-    SCM_WTA_DISPATCH_1 (g_scm_sys_atanh, z, 1, s_scm_sys_atanh);
+    return scm_wta_dispatch_1 (g_scm_sys_atanh, z, 1, s_scm_sys_atanh);
 }
 #undef FUNC_NAME
 
@@ -8718,7 +8727,7 @@ SCM_PRIMITIVE_GENERIC (scm_real_part, "real-part", 1, 0, 0,
   else if (SCM_I_INUMP (z) || SCM_BIGP (z) || SCM_REALP (z) || SCM_FRACTIONP (z))
     return z;
   else
-    SCM_WTA_DISPATCH_1 (g_scm_real_part, z, SCM_ARG1, s_scm_real_part);
+    return scm_wta_dispatch_1 (g_scm_real_part, z, SCM_ARG1, s_scm_real_part);
 }
 #undef FUNC_NAME
 
@@ -8733,7 +8742,7 @@ SCM_PRIMITIVE_GENERIC (scm_imag_part, "imag-part", 1, 0, 0,
   else if (SCM_I_INUMP (z) || SCM_REALP (z) || SCM_BIGP (z) || SCM_FRACTIONP (z))
     return SCM_INUM0;
   else
-    SCM_WTA_DISPATCH_1 (g_scm_imag_part, z, SCM_ARG1, s_scm_imag_part);
+    return scm_wta_dispatch_1 (g_scm_imag_part, z, SCM_ARG1, s_scm_imag_part);
 }
 #undef FUNC_NAME
 
@@ -8749,7 +8758,7 @@ SCM_PRIMITIVE_GENERIC (scm_numerator, "numerator", 1, 0, 0,
   else if (SCM_REALP (z))
     return scm_exact_to_inexact (scm_numerator (scm_inexact_to_exact (z)));
   else
-    SCM_WTA_DISPATCH_1 (g_scm_numerator, z, SCM_ARG1, s_scm_numerator);
+    return scm_wta_dispatch_1 (g_scm_numerator, z, SCM_ARG1, s_scm_numerator);
 }
 #undef FUNC_NAME
 
@@ -8766,7 +8775,8 @@ SCM_PRIMITIVE_GENERIC (scm_denominator, "denominator", 1, 0, 0,
   else if (SCM_REALP (z))
     return scm_exact_to_inexact (scm_denominator (scm_inexact_to_exact (z)));
   else
-    SCM_WTA_DISPATCH_1 (g_scm_denominator, z, SCM_ARG1, s_scm_denominator);
+    return scm_wta_dispatch_1 (g_scm_denominator, z, SCM_ARG1,
+                               s_scm_denominator);
 }
 #undef FUNC_NAME
 
@@ -8808,7 +8818,8 @@ SCM_PRIMITIVE_GENERIC (scm_magnitude, "magnitude", 1, 0, 0,
                             SCM_FRACTION_DENOMINATOR (z));
     }
   else
-    SCM_WTA_DISPATCH_1 (g_scm_magnitude, z, SCM_ARG1, s_scm_magnitude);
+    return scm_wta_dispatch_1 (g_scm_magnitude, z, SCM_ARG1,
+                               s_scm_magnitude);
 }
 #undef FUNC_NAME
 
@@ -8854,7 +8865,7 @@ SCM_PRIMITIVE_GENERIC (scm_angle, "angle", 1, 0, 0,
       else return scm_from_double (atan2 (0.0, -1.0));
     }
   else
-    SCM_WTA_DISPATCH_1 (g_scm_angle, z, SCM_ARG1, s_scm_angle);
+    return scm_wta_dispatch_1 (g_scm_angle, z, SCM_ARG1, s_scm_angle);
 }
 #undef FUNC_NAME
 
@@ -8873,7 +8884,8 @@ SCM_PRIMITIVE_GENERIC (scm_exact_to_inexact, "exact->inexact", 1, 0, 0,
   else if (SCM_INEXACTP (z))
     return z;
   else
-    SCM_WTA_DISPATCH_1 (g_scm_exact_to_inexact, z, 1, s_scm_exact_to_inexact);
+    return scm_wta_dispatch_1 (g_scm_exact_to_inexact, z, 1,
+                               s_scm_exact_to_inexact);
 }
 #undef FUNC_NAME
 
@@ -8894,7 +8906,8 @@ SCM_PRIMITIVE_GENERIC (scm_inexact_to_exact, "inexact->exact", 1, 0, 0,
       else if (SCM_COMPLEXP (z) && SCM_COMPLEX_IMAG (z) == 0.0)
        val = SCM_COMPLEX_REAL (z);
       else
-       SCM_WTA_DISPATCH_1 (g_scm_inexact_to_exact, z, 1, s_scm_inexact_to_exact);
+       return scm_wta_dispatch_1 (g_scm_inexact_to_exact, z, 1,
+                                   s_scm_inexact_to_exact);
 
       if (!SCM_LIKELY (DOUBLE_IS_FINITE (val)))
        SCM_OUT_OF_RANGE (1, z);
@@ -9282,46 +9295,6 @@ scm_from_double (double val)
   return z;
 }
 
-#if SCM_ENABLE_DEPRECATED == 1
-
-float
-scm_num2float (SCM num, unsigned long pos, const char *s_caller)
-{
-  scm_c_issue_deprecation_warning
-    ("`scm_num2float' is deprecated. Use scm_to_double instead.");
-
-  if (SCM_BIGP (num))
-    {
-      float res = mpz_get_d (SCM_I_BIG_MPZ (num));
-      if (!isinf (res))
-       return res;
-      else
-       scm_out_of_range (NULL, num);
-    }
-  else
-    return scm_to_double (num);
-}
-
-double
-scm_num2double (SCM num, unsigned long pos, const char *s_caller)
-{
-  scm_c_issue_deprecation_warning
-    ("`scm_num2double' is deprecated. Use scm_to_double instead.");
-
-  if (SCM_BIGP (num))
-    {
-      double res = mpz_get_d (SCM_I_BIG_MPZ (num));
-      if (!isinf (res))
-       return res;
-      else
-       scm_out_of_range (NULL, num);
-    }
-  else
-    return scm_to_double (num);
-}
-
-#endif
-
 int
 scm_is_complex (SCM val)
 {
@@ -9445,7 +9418,8 @@ SCM_PRIMITIVE_GENERIC (scm_log, "log", 1, 0, 0,
 {
   if (SCM_COMPLEXP (z))
     {
-#if HAVE_COMPLEX_DOUBLE && HAVE_CLOG && defined (SCM_COMPLEX_VALUE)
+#if defined HAVE_COMPLEX_DOUBLE && defined HAVE_CLOG \
+  && defined (SCM_COMPLEX_VALUE)
       return scm_from_complex_double (clog (SCM_COMPLEX_VALUE (z)));
 #else
       double re = SCM_COMPLEX_REAL (z);
@@ -9470,7 +9444,7 @@ SCM_PRIMITIVE_GENERIC (scm_log, "log", 1, 0, 0,
     return log_of_fraction (SCM_FRACTION_NUMERATOR (z),
                            SCM_FRACTION_DENOMINATOR (z));
   else
-    SCM_WTA_DISPATCH_1 (g_scm_log, z, 1, s_scm_log);
+    return scm_wta_dispatch_1 (g_scm_log, z, 1, s_scm_log);
 }
 #undef FUNC_NAME
 
@@ -9517,7 +9491,7 @@ SCM_PRIMITIVE_GENERIC (scm_log10, "log10", 1, 0, 0,
                        log_of_fraction (SCM_FRACTION_NUMERATOR (z),
                                         SCM_FRACTION_DENOMINATOR (z)));
   else
-    SCM_WTA_DISPATCH_1 (g_scm_log10, z, 1, s_scm_log10);
+    return scm_wta_dispatch_1 (g_scm_log10, z, 1, s_scm_log10);
 }
 #undef FUNC_NAME
 
@@ -9530,7 +9504,8 @@ SCM_PRIMITIVE_GENERIC (scm_exp, "exp", 1, 0, 0,
 {
   if (SCM_COMPLEXP (z))
     {
-#if HAVE_COMPLEX_DOUBLE && HAVE_CEXP && defined (SCM_COMPLEX_VALUE)
+#if defined HAVE_COMPLEX_DOUBLE && defined HAVE_CEXP \
+  && defined (SCM_COMPLEX_VALUE)
       return scm_from_complex_double (cexp (SCM_COMPLEX_VALUE (z)));
 #else
       return scm_c_make_polar (exp (SCM_COMPLEX_REAL (z)),
@@ -9544,10 +9519,74 @@ SCM_PRIMITIVE_GENERIC (scm_exp, "exp", 1, 0, 0,
       return scm_from_double (exp (scm_to_double (z)));
     }
   else
-    SCM_WTA_DISPATCH_1 (g_scm_exp, z, 1, s_scm_exp);
+    return scm_wta_dispatch_1 (g_scm_exp, z, 1, s_scm_exp);
+}
+#undef FUNC_NAME
+
+
+SCM_DEFINE (scm_i_exact_integer_sqrt, "exact-integer-sqrt", 1, 0, 0,
+           (SCM k),
+           "Return two exact non-negative integers @var{s} and @var{r}\n"
+           "such that @math{@var{k} = @var{s}^2 + @var{r}} and\n"
+           "@math{@var{s}^2 <= @var{k} < (@var{s} + 1)^2}.\n"
+           "An error is raised if @var{k} is not an exact non-negative integer.\n"
+           "\n"
+           "@lisp\n"
+           "(exact-integer-sqrt 10) @result{} 3 and 1\n"
+           "@end lisp")
+#define FUNC_NAME s_scm_i_exact_integer_sqrt
+{
+  SCM s, r;
+
+  scm_exact_integer_sqrt (k, &s, &r);
+  return scm_values (scm_list_2 (s, r));
 }
 #undef FUNC_NAME
 
+void
+scm_exact_integer_sqrt (SCM k, SCM *sp, SCM *rp)
+{
+  if (SCM_LIKELY (SCM_I_INUMP (k)))
+    {
+      scm_t_inum kk = SCM_I_INUM (k);
+      scm_t_inum uu = kk;
+      scm_t_inum ss;
+
+      if (SCM_LIKELY (kk > 0))
+       {
+         do
+           {
+             ss = uu;
+             uu = (ss + kk/ss) / 2;
+           } while (uu < ss);
+         *sp = SCM_I_MAKINUM (ss);
+         *rp = SCM_I_MAKINUM (kk - ss*ss);
+       }
+      else if (SCM_LIKELY (kk == 0))
+       *sp = *rp = SCM_INUM0;
+      else
+       scm_wrong_type_arg_msg ("exact-integer-sqrt", SCM_ARG1, k,
+                               "exact non-negative integer");
+    }
+  else if (SCM_LIKELY (SCM_BIGP (k)))
+    {
+      SCM s, r;
+
+      if (mpz_sgn (SCM_I_BIG_MPZ (k)) < 0)
+       scm_wrong_type_arg_msg ("exact-integer-sqrt", SCM_ARG1, k,
+                               "exact non-negative integer");
+      s = scm_i_mkbig ();
+      r = scm_i_mkbig ();
+      mpz_sqrtrem (SCM_I_BIG_MPZ (s), SCM_I_BIG_MPZ (r), SCM_I_BIG_MPZ (k));
+      scm_remember_upto_here_1 (k);
+      *sp = scm_i_normbig (s);
+      *rp = scm_i_normbig (r);
+    }
+  else
+    scm_wrong_type_arg_msg ("exact-integer-sqrt", SCM_ARG1, k,
+                           "exact non-negative integer");
+}
+
 
 SCM_PRIMITIVE_GENERIC (scm_sqrt, "sqrt", 1, 0, 0,
                       (SCM z),
@@ -9585,7 +9624,7 @@ SCM_PRIMITIVE_GENERIC (scm_sqrt, "sqrt", 1, 0, 0,
         return scm_from_double (sqrt (xx));
     }
   else
-    SCM_WTA_DISPATCH_1 (g_scm_sqrt, z, 1, s_scm_sqrt);
+    return scm_wta_dispatch_1 (g_scm_sqrt, z, 1, s_scm_sqrt);
 }
 #undef FUNC_NAME