r6rs fldiv, etc. need to return nan for zero divisor

svn: r11012

collects/rnrs/arithmetic/flonums-6.ss

@@ -49,24 +49,56 @@
 
 (define-fl abs flabs (a) nocheck)
 
-(provide fldiv-and-mod
-         fldiv0-and-mod0)
+(provide fldiv flmod fldiv-and-mod
+         fldiv0 flmod0 fldiv0-and-mod0)
+(define (fldiv a b)
+  (unless (inexact-real? a)
+    (raise-type-error 'fldiv "flonum" a))
+  (unless (inexact-real? b)
+    (raise-type-error 'fldiv "flonum" b))
+  (if (zero? b)
+      +nan.0
+      (div a b)))
+(define (flmod a b)
+  (unless (inexact-real? a)
+    (raise-type-error 'flmod "flonum" a))
+  (unless (inexact-real? b)
+    (raise-type-error 'flmod "flonum" b))
+  (if (zero? b)
+      +nan.0
+      (mod a b)))
 (define (fldiv-and-mod a b)
   (unless (inexact-real? a)
     (raise-type-error 'fldiv-and-mod "flonum" a))
   (unless (inexact-real? b)
     (raise-type-error 'fldiv-and-mod "flonum" b))
-  (div-and-mod a b))
-(define-fl div fldiv (a b) nocheck)
-(define-fl mod flmod (a b) nocheck)
+  (if (zero? b)
+      (values +nan.0 +nan.0)
+      (div-and-mod a b)))
 (define (fldiv0-and-mod0 a b)
   (unless (inexact-real? a)
     (raise-type-error 'fldiv0-and-mod0 "flonum" a))
   (unless (inexact-real? b)
     (raise-type-error 'fldiv0-and-mod0 "flonum" b))
-  (div0-and-mod0 a b))
-(define-fl div0 fldiv0 (a b) nocheck)
-(define-fl mod0 flmod0 (a b) nocheck)
+  (if (zero? b)
+      (values +nan.0 +nan.0)
+      (div0-and-mod0 a b)))
+(define (fldiv0 a b)
+  (unless (inexact-real? a)
+    (raise-type-error 'fldiv0 "flonum" a))
+  (unless (inexact-real? b)
+    (raise-type-error 'fldiv0 "flonum" b))
+  (if (zero? b)
+      +nan.0
+      (div0 a b)))
+(define (flmod0 a b)
+  (unless (inexact-real? a)
+    (raise-type-error 'flmod0 "flonum" a))
+  (unless (inexact-real? b)
+    (raise-type-error 'flmod0 "flonum" b))
+  (if (zero? b)
+      +nan.0
+      (mod0 a b)))
 
 (define (flnumerator c)
   (if (inexact-real? c)