Use casts for finicky comparison signedness

Author: sodabrew

ext/mysql2/client.c

@@ -349,7 +349,7 @@ static VALUE rb_connect(VALUE self, VALUE user, VALUE pass, VALUE host, VALUE po
         /* avoid an early timeout due to time truncating milliseconds off the start time */
         if (elapsed_time > 0)
           elapsed_time--;
-        if (elapsed_time >= wrapper->connect_timeout)
+        if (elapsed_time >= (time_t)wrapper->connect_timeout)
           break;
         connect_timeout = wrapper->connect_timeout - elapsed_time;
         mysql_options(wrapper->client, MYSQL_OPT_CONNECT_TIMEOUT, &connect_timeout);

ext/mysql2/result.c

@@ -747,7 +747,7 @@ static VALUE rb_mysql_result_fetch_fields(VALUE self) {
     wrapper->fields = rb_ary_new2(wrapper->numberOfFields);
   }
 
-  if (RARRAY_LEN(wrapper->fields) != wrapper->numberOfFields) {
+  if ((unsigned)RARRAY_LEN(wrapper->fields) != wrapper->numberOfFields) {
     for (i=0; i<wrapper->numberOfFields; i++) {
       rb_mysql_result_fetch_field(self, i, symbolizeKeys);
     }