X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcode%2Ffloat.lisp;h=3b5690b15d997f4eff494d9ed55226f62f3b08f3;hb=b31eab5875e8058a2fdfcb879e23c2724d25a278;hp=88ffb3784ef85c8737a076e77b8001f28ce238e6;hpb=b049b6c0e09815ca01f79090dd8343efcaac72a1;p=sbcl.git

diff --git a/src/code/float.lisp b/src/code/float.lisp
index 88ffb37..3b5690b 100644
--- a/src/code/float.lisp
+++ b/src/code/float.lisp
@@ -810,12 +810,13 @@
          (truly-the fixnum (%unary-round number))
          (multiple-value-bind (bits exp) (integer-decode-float number)
            (let* ((shifted (ash bits exp))
-                  (rounded (if (and (minusp exp)
-                                    (oddp shifted)
-                                    (eql (logand bits
-                                                 (lognot (ash -1 (- exp))))
-                                         (ash 1 (- -1 exp))))
-                               (1+ shifted)
+                  (rounded (if (minusp exp)
+                               (let ((fractional-bits (logand bits (lognot (ash -1 (- exp)))))
+                                     (0.5bits (ash 1 (- -1 exp))))
+                                 (cond
+                                   ((> fractional-bits 0.5bits) (1+ shifted))
+                                   ((< fractional-bits 0.5bits) shifted)
+                                   (t (if (oddp shifted) (1+ shifted) shifted))))
                                shifted)))
              (if (minusp number)
                  (- rounded)