Fix some warnings on OS X

Author: nobu-k

test/object_with_zone.cpp

@@ -908,7 +908,7 @@ TEST(object_with_zone, forward_list)
         msgpack::object obj(v1, z);
         EXPECT_EQ(obj.as<forward_list<int> >(), v1);
         v1.front() = 42;
-        EXPECT_EQ(obj.as<forward_list<int> >().front(), kElements - 1);
+        EXPECT_EQ(obj.as<forward_list<int> >().front(), static_cast<int>(kElements - 1));
     }
 }
 

test/pack_unpack.cpp

@@ -332,7 +332,7 @@ TEST(unpack, insufficient_bytes_ref)
     }
     catch (msgpack::insufficient_bytes const&) {
         EXPECT_TRUE(true);
-        EXPECT_EQ(off, 0);
+        EXPECT_EQ(off, 0u);
     }
 }
 
@@ -350,7 +350,7 @@ TEST(unpack, insufficient_bytes_object_handle)
     }
     catch (msgpack::insufficient_bytes const&) {
         EXPECT_TRUE(true);
-        EXPECT_EQ(off, 0);
+        EXPECT_EQ(off, 0u);
     }
 }
 
@@ -369,6 +369,6 @@ TEST(unpack, insufficient_bytes_zone)
     }
     catch (msgpack::insufficient_bytes const&) {
         EXPECT_TRUE(true);
-        EXPECT_EQ(off, 0);
+        EXPECT_EQ(off, 0u);
     }
 }

test/pack_unpack_c.cpp

@@ -83,7 +83,7 @@ TEST(pack, insufficient)
 
     success = msgpack_unpack_next(&msg, sbuf->data, 1, &offset);
     EXPECT_EQ(MSGPACK_UNPACK_CONTINUE, success);
-    EXPECT_EQ(0, offset);
+    EXPECT_EQ(0u, offset);
 
     msgpack_unpacked_destroy(&msg);