config: add comment clarifying virtual destructor.

Just in case anybody else is like me and gets confused.

Signed-off-by: Greg Farnum <gregory.farnum@dreamhost.com>

diff --git a/src/common/config.h b/src/common/config.h
index 54d49942b6c76e63f2602e24fd7954066beedebe..93565f19f4dccd5c62e6b206b4d8e481721cbcf4 100644 (file)
--- a/src/common/config.h
+++ b/src/common/config.h
@@ -527,7 +527,8 @@ struct config_option {
 
 class md_config_obs_t {
 public:
-  virtual ~md_config_obs_t();
+  virtual ~md_config_obs_t(); // we won't actually use this, but it's safest
+  // when you have virtual functions
   virtual const char** get_tracked_conf_keys() const = 0;
   virtual void handle_conf_change(const md_config_t *conf,
                          const std::set <std::string> &changed) = 0;