diff --git a/ci/build_cmake.sh b/ci/build_cmake.sh
index e10d8ceb..4c07a09c 100755
--- a/ci/build_cmake.sh
+++ b/ci/build_cmake.sh
@@ -26,7 +26,7 @@ else
     export ARCH_FLAG="-m64"
 fi
 
-cmake -DMSGPACK_CXX11=${CXX11} -DMSGPACK_CXX17=${CXX17} -DMSGPACK_32BIT=${BIT32} -DMSGPACK_CHAR_SIGN=${CHAR_SIGN} -DMSGPACK_DEFAULT_API_VERSION=${API_VERSION} -DMSGPACK_USE_X3_PARSE=${X3_PARSE} -DCMAKE_CXX_FLAGS=${ARCH_FLAG} ${ZLIB32} -fsanitize=undefined ..
+cmake -DMSGPACK_CXX11=${CXX11} -DMSGPACK_CXX17=${CXX17} -DMSGPACK_32BIT=${BIT32} -DMSGPACK_CHAR_SIGN=${CHAR_SIGN} -DMSGPACK_DEFAULT_API_VERSION=${API_VERSION} -DMSGPACK_USE_X3_PARSE=${X3_PARSE} -DCMAKE_CXX_FLAGS="${ARCH_FLAG} ${CXXFLAGS} -fsanitize=undefined" ${ZLIB32} ..
 
 ret=$?
 if [ $ret -ne 0 ]
diff --git a/include/msgpack/v1/adaptor/boost/fusion.hpp b/include/msgpack/v1/adaptor/boost/fusion.hpp
index 73e1766b..d47a7f24 100644
--- a/include/msgpack/v1/adaptor/boost/fusion.hpp
+++ b/include/msgpack/v1/adaptor/boost/fusion.hpp
@@ -21,11 +21,23 @@
 #include "msgpack/adaptor/cpp11/tuple.hpp"
 #endif // #if !defined (MSGPACK_USE_CPP03)
 
+#if defined(__GNUC__)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wconversion"
+#endif // defined(__GNUC__)
+
 #include <boost/fusion/support/is_sequence.hpp>
 #include <boost/fusion/sequence/intrinsic/size.hpp>
 #include <boost/fusion/algorithm/iteration/for_each.hpp>
 #include <boost/fusion/sequence/intrinsic/at.hpp>
 #include <boost/fusion/include/mpl.hpp>
+
+
+#if defined(__GNUC__)
+#pragma GCC diagnostic pop
+#endif // defined(__GNUC__)
+
+
 #include <boost/mpl/size.hpp>
 
 namespace msgpack {
diff --git a/include/msgpack/v1/adaptor/boost/msgpack_variant.hpp b/include/msgpack/v1/adaptor/boost/msgpack_variant.hpp
index acd35d52..ecf8ac17 100644
--- a/include/msgpack/v1/adaptor/boost/msgpack_variant.hpp
+++ b/include/msgpack/v1/adaptor/boost/msgpack_variant.hpp
@@ -26,7 +26,18 @@
 #include "msgpack/adaptor/vector.hpp"
 #include "msgpack/adaptor/map.hpp"
 
+
+#if defined(__GNUC__)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wconversion"
+#endif // defined(__GNUC__)
+
 #include <boost/variant.hpp>
+
+#if defined(__GNUC__)
+#pragma GCC diagnostic pop
+#endif // defined(__GNUC__)
+
 #include <boost/operators.hpp>
 
 namespace msgpack {
diff --git a/include/msgpack/v1/adaptor/boost/optional.hpp b/include/msgpack/v1/adaptor/boost/optional.hpp
index 70791fe9..bd51cdf2 100644
--- a/include/msgpack/v1/adaptor/boost/optional.hpp
+++ b/include/msgpack/v1/adaptor/boost/optional.hpp
@@ -14,6 +14,11 @@
 #include "msgpack/adaptor/adaptor_base.hpp"
 #include "msgpack/adaptor/check_container_size.hpp"
 
+#if defined(__GNUC__)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wconversion"
+#endif // defined(__GNUC__)
+
 // To suppress warning on Boost.1.58.0
 #if defined(__GNUC__) && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)) || defined(__clang__)
 #pragma GCC diagnostic push
@@ -26,6 +31,10 @@
 #pragma GCC diagnostic pop
 #endif // defined(__GNUC__) && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)) || defined(__clang__)
 
+#if defined(__GNUC__)
+#pragma GCC diagnostic pop
+#endif // defined(__GNUC__)
+
 namespace msgpack {
 
 /// @cond
diff --git a/test/msgpack_cpp11.cpp b/test/msgpack_cpp11.cpp
index c5c532bf..f3569293 100644
--- a/test/msgpack_cpp11.cpp
+++ b/test/msgpack_cpp11.cpp
@@ -1461,7 +1461,7 @@ TEST(MSGPACK_TIMESPEC, timespec_object_with_zone_zero)
 TEST(MSGPACK_TIMESPEC, timespec_pack_convert_32bit_sec)
 {
     std::stringstream ss;
-    timespec val1{ std::numeric_limits<decltype(std::declval<timespec>().tv_sec)>::is_signed ? INT32_MAX : UINT32_MAX, 0 };
+    timespec val1{ std::numeric_limits<decltype(std::declval<timespec>().tv_sec)>::is_signed ? time_t(INT32_MAX) : time_t(UINT32_MAX), 0 };
 
     msgpack::pack(ss, val1);
     std::string const& str = ss.str();
@@ -1477,7 +1477,7 @@ TEST(MSGPACK_TIMESPEC, timespec_pack_convert_32bit_sec)
 TEST(MSGPACK_TIMESPEC, timespec_object_with_zone_32bit_sec)
 {
     msgpack::zone z;
-    timespec val1{ std::numeric_limits<decltype(std::declval<timespec>().tv_sec)>::is_signed ? INT32_MAX : UINT32_MAX, 0 };
+    timespec val1{ std::numeric_limits<decltype(std::declval<timespec>().tv_sec)>::is_signed ? time_t(INT32_MAX) : time_t(UINT32_MAX), 0 };
     msgpack::object obj(val1, z);
     timespec val2 = obj.as<timespec>();
     EXPECT_EQ(val1.tv_sec, val2.tv_sec);