Tweak the float hashing algorithm to perform fewer calls to ldexp for some

types and possibly generate a better hash value.


[SVN r34273]

libs/functional

@@ -1 +1 @@
-Subproject commit a4d9b52094098474d1ba3772ca20e7b6ccdec6b4
+Subproject commit cae97c67d8cf3ef9a3582eed309c544ebe3d51eb