diff --git a/hash/doc/changes.qbk b/hash/doc/changes.qbk
index f7ab411..ba870de 100644
--- a/hash/doc/changes.qbk
+++ b/hash/doc/changes.qbk
@@ -179,4 +179,8 @@
 * Fixed strict aliasing violation
   ([@https://github.com/boostorg/functional/pull/3 GitHub #3]).
 
+[h2 Boost 1.63.0]
+
+* Fixed some warnings.
+
 [endsect]
diff --git a/hash/test/Jamfile.v2 b/hash/test/Jamfile.v2
index ca4903b..1da2da8 100644
--- a/hash/test/Jamfile.v2
+++ b/hash/test/Jamfile.v2
@@ -12,7 +12,7 @@ project hash-tests
         #<toolset>intel:<cxxflags>-strict-ansi
         <toolset>gcc:<cxxflags>"-pedantic -Wstrict-aliasing -fstrict-aliasing -Wextra -Wsign-promo -Wunused-parameter -Wconversion -Wfloat-equal -Wshadow"
         <toolset>darwin:<cxxflags>"-pedantic -Wstrict-aliasing -fstrict-aliasing -Wextra -Wsign-promo -Wunused-parameter -Wconversion -Wfloat-equal -Wshadow"
-        <toolset>clang:<cxxflags>"-pedantic -Wstrict-aliasing -fstrict-aliasing -Wextra -Wsign-promo -Wunused-parameter -Wconversion -Wfloat-equal -Wshadow"
+        <toolset>clang:<cxxflags>"-pedantic -Wstrict-aliasing -fstrict-aliasing -Wextra -Wsign-promo -Wunused-parameter -Wsign-conversion -Wconversion -Wfloat-equal -Wshadow"
         #<toolset>msvc:<warnings-as-errors>on
         #<toolset>gcc:<warnings-as-errors>on
         #<toolset>darwin:<warnings-as-errors>on
diff --git a/include/boost/functional/hash/hash.hpp b/include/boost/functional/hash/hash.hpp
index 0a8ceeb..2e21091 100644
--- a/include/boost/functional/hash/hash.hpp
+++ b/include/boost/functional/hash/hash.hpp
@@ -168,10 +168,10 @@ namespace boost
         template <class T>
         inline std::size_t hash_value_signed(T val)
         {
-             const int size_t_bits = std::numeric_limits<std::size_t>::digits;
+             const unsigned int size_t_bits = std::numeric_limits<std::size_t>::digits;
              // ceiling(std::numeric_limits<T>::digits / size_t_bits) - 1
              const int length = (std::numeric_limits<T>::digits - 1)
-                 / size_t_bits;
+                 / static_cast<int>(size_t_bits);
 
              std::size_t seed = 0;
              T positive = val < 0 ? -1 - val : val;
@@ -189,10 +189,10 @@ namespace boost
         template <class T>
         inline std::size_t hash_value_unsigned(T val)
         {
-             const int size_t_bits = std::numeric_limits<std::size_t>::digits;
+             const unsigned int size_t_bits = std::numeric_limits<std::size_t>::digits;
              // ceiling(std::numeric_limits<T>::digits / size_t_bits) - 1
              const int length = (std::numeric_limits<T>::digits - 1)
-                 / size_t_bits;
+                 / static_cast<int>(size_t_bits);
 
              std::size_t seed = 0;
 
@@ -236,7 +236,7 @@ namespace boost
         inline void hash_combine_impl(boost::uint64_t& h,
                 boost::uint64_t k)
         {
-            const uint64_t m = UINT64_C(0xc6a4a7935bd1e995);
+            const boost::uint64_t m = UINT64_C(0xc6a4a7935bd1e995);
             const int r = 47;
 
             k *= m;