X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcode%2Firrat.lisp;h=c4e9ad46387daaf3b3f2b13a16cee2efb1e2493e;hb=2a03fda8299baea66cb9a6955d414dcc27af5ac9;hp=5f901c910233db1e52550551e29bae529234b101;hpb=1b87bfbe482c555879d2a902e88f9d147ead394e;p=sbcl.git

diff --git a/src/code/irrat.lisp b/src/code/irrat.lisp
index 5f901c9..c4e9ad4 100644
--- a/src/code/irrat.lisp
+++ b/src/code/irrat.lisp
@@ -211,6 +211,7 @@
                    (when (zerop (logior y-ihi y-lo))
                      (return-from real-expt (coerce 1d0 rtype)))
                    ;; +-NaN return x+y
+                   ;; FIXME: Hardcoded qNaN/sNaN values are not portable.
                    (when (or (> x-ihi #x7ff00000)
                              (and (= x-ihi #x7ff00000) (/= x-lo 0))
                              (> y-ihi #x7ff00000)
@@ -334,11 +335,20 @@
   "Return the logarithm of NUMBER in the base BASE, which defaults to e."
   (if base-p
       (cond
-        ((zerop base) 0f0) ; FIXME: type
+        ((zerop base)
+         (if (or (typep number 'double-float) (typep base 'double-float))
+             0.0d0
+             0.0f0))
         ((and (typep number '(integer (0) *))
               (typep base '(integer (0) *)))
          (coerce (/ (log2 number) (log2 base)) 'single-float))
-        (t (/ (log number) (log base))))
+        ((and (typep number 'integer) (typep base 'double-float))
+         ;; No single float intermediate result
+         (/ (log2 number) (log base 2.0d0)))
+        ((and (typep number 'double-float) (typep base 'integer))
+         (/ (log number 2.0d0) (log2 base)))
+        (t
+         (/ (log number) (log base))))
       (number-dispatch ((number number))
         (((foreach fixnum bignum))
          (if (minusp number)