--- cvsroot/microscheme/scheme.c	2015/12/01 02:42:35	1.54
+++ cvsroot/microscheme/scheme.c	2015/12/01 03:03:11	1.55
@@ -4001,20 +4001,21 @@
     {
 #if USE_MATH
       case OP_INEX2EX:         /* inexact->exact */
-        {
-          if (is_integer (x))
-            s_return (x);
+        if (!is_integer (x))
+          {
+            RVALUE r = rvalue_unchecked (x);
 
-          RVALUE r = rvalue_unchecked (x);
+            if (r == (RVALUE)(IVALUE)r)
+              x = mk_integer (SCHEME_A_ rvalue_unchecked (x));
+            else
+              Error_1 ("inexact->exact: not integral:", x);
+          }
 
-          if (r == (RVALUE)(IVALUE)r)
-            s_return (mk_integer (SCHEME_A_ rvalue_unchecked (x)));
-          else
-            Error_1 ("inexact->exact: not integral:", x);
-        }
+        s_return (x);
 
       case OP_EXP:  s_return (mk_real (SCHEME_A_ exp  (rvalue (x))));
-      case OP_LOG:  s_return (mk_real (SCHEME_A_ log  (rvalue (x))));
+      case OP_LOG:  s_return (mk_real (SCHEME_A_ log  (rvalue (x))
+                                                 / (cadr (args) == NIL ? 1 : log (rvalue (cadr (args))))));
       case OP_SIN:  s_return (mk_real (SCHEME_A_ sin  (rvalue (x))));
       case OP_COS:  s_return (mk_real (SCHEME_A_ cos  (rvalue (x))));
       case OP_TAN:  s_return (mk_real (SCHEME_A_ tan  (rvalue (x))));
@@ -4022,13 +4023,10 @@
       case OP_ACOS: s_return (mk_real (SCHEME_A_ acos (rvalue (x))));
 
       case OP_ATAN:
-        if (cdr (args) == NIL)
-          s_return (mk_real (SCHEME_A_ atan (rvalue (x))));
-        else
-          {
-            pointer y = cadr (args);
-            s_return (mk_real (SCHEME_A_ atan2 (rvalue (x), rvalue (y))));
-          }
+        s_return (mk_real (SCHEME_A_
+           cdr (args) == NIL
+             ? atan (rvalue (x))
+             : atan2 (rvalue (x), rvalue (cadr (args)))));
 
       case OP_SQRT:
         s_return (mk_real (SCHEME_A_ sqrt (rvalue (x))));