diff --git a/test/FixedPointMathLib.t.sol b/test/FixedPointMathLib.t.sol
index 6d2e85e4e..1e816510d 100644
--- a/test/FixedPointMathLib.t.sol
+++ b/test/FixedPointMathLib.t.sol
@@ -928,6 +928,7 @@ contract FixedPointMathLibTest is SoladyTest {
         assertEq(FixedPointMathLib.log2(10), 3);
         assertEq(FixedPointMathLib.log2(20), 4);
         assertEq(FixedPointMathLib.log2(30), 4);
+        assertEq(FixedPointMathLib.log2(40), 5);
         assertEq(FixedPointMathLib.log2(1024), 10);
         assertEq(FixedPointMathLib.log2(1048576), 20);
         assertEq(FixedPointMathLib.log2(1073741824), 30);