--- a/Float.st	Tue Jun 20 12:19:25 2017 +0200
+++ b/Float.st	Tue Jun 20 12:22:03 2017 +0200
@@ -754,13 +754,14 @@
 %}
 
     "
-	self getFPUControl
+     self getFPUControl
     "
+
+    "Modified (comment): / 20-06-2017 / 11:51:58 / cg"
 !
 
 setFPUControl
-    "set the fpu control word.
-     We want 64 bit precision for long double here"
+    "BORLAND only: set the fpu control word for 64 bit precision for long doubles here"
 
 %{
 #ifdef __BORLANDC__
@@ -773,8 +774,10 @@
 %}
 
     "
-	self setFPUControl
+     self setFPUControl
     "
+
+    "Modified (comment): / 20-06-2017 / 11:51:54 / cg"
 ! !
 
 !Float class methodsFor:'queries'!
@@ -2327,7 +2330,7 @@
 !Float methodsFor:'special access'!
 
 exponent
-    "extract a normalized floats exponent.
+    "extract a normalized float's exponent.
      The returned value depends on the float-representation of
      the underlying machine and is therefore highly unportable.
      This is not for general use.
@@ -2335,13 +2338,22 @@
      0.5 .. 1.0 and the float's value is: mantissa * 2^exp"
 
 %{  /* NOCONTEXT */
-
+    double myVal;
     double frac;
     int exp;
 
-    frac = frexp(__floatVal(self), &exp);
-    RETURN (__mkSmallInteger(exp));
+    myVal = __floatVal(self);
+    // ouch: math libs seem to not care for NaN here;
+#if 1
+    // should we?
+    if (! (isnan(myVal) || isinf(myVal)))
+#endif
+    {
+        frac = frexp(myVal, &exp);
+        RETURN (__mkSmallInteger(exp));
+    }
 %}.
+    ^ super exponent
 
     "
      1.0 exponent
@@ -2353,7 +2365,11 @@
      0.25 exponent
      0.2 exponent
      0.00000011111 exponent
+     0.0 exponent
+     1e1000 exponent
     "
+
+    "Modified: / 20-06-2017 / 11:34:43 / cg"
 !
 
 mantissa
@@ -2365,12 +2381,20 @@
      0.5 .. 1.0 and the floats value is mantissa * 2^exp"
 
 %{  /* NOCONTEXT */
-
+    double myVal;
     double frac;
     int exp;
 
-    frac = frexp(__floatVal(self), &exp);
-    RETURN (__MKFLOAT(frac));
+    myVal = __floatVal(self);
+    // ouch: math libs seem to not care for NaN here;
+#if 1
+    // should we?
+    if (! (isnan(myVal) || isinf(myVal)))
+#endif
+    {
+        frac = frexp(myVal, &exp);
+        RETURN (__MKFLOAT(frac));
+    }    
 %}.
     ^ super mantissa
 
@@ -2383,7 +2407,11 @@
 
      0.00000011111 exponent
      0.00000011111 mantissa
+
+     1e1000 mantissa
     "
+
+    "Modified: / 20-06-2017 / 11:37:13 / cg"
 ! !
 
 !Float methodsFor:'testing'!