diff --git a/tests/float.lisp b/tests/float.lisp
index eeb221b1d8664c3596af76b6f7b0d2b7f3cd2e30..55b901334fe1ef6f24b600f5819f623ed6a83cce 100644
--- a/tests/float.lisp
+++ b/tests/float.lisp
@@ -21,3 +21,25 @@
     (let ((x (float (expt 10 k) 1d0)))
       (assert-equalp k (log x 10)))))
 
+(compile 'clog2
+	 #'(lambda (x)
+	     (declare (type (double-float (0d0)) x))
+	     (log x 2)))
+
+(compile 'clog10
+	 #'(lambda (x)
+	     (declare (type (double-float (0d0)) x))
+	     (log x 10)))
+
+(define-test log2.compiled
+  (loop for k from -1074 to 1023 do
+    (let ((x (scale-float 1d0 k)))
+      (assert-equalp k (clog2 x)))))
+
+(define-test log10.compiled
+  (loop for k from 0 to 22 do
+    (let ((x (float (expt 10 k) 1d0)))
+      (assert-equalp k (clog10 x)))))
+
+
+