librbd: handle NULL old_format pointer in detect_format()'s logging

Signed-off-by: Dan Mick <dan.mick@inktank.com>

diff --git a/src/librbd.cc b/src/librbd.cc
index 2881e246c2e92faeff557f37a7bc36ceeee78449..e5178679d6c9ac7e6b75ed921c0d0db9fd97341a 100644 (file)
--- a/src/librbd.cc
+++ b/src/librbd.cc
@@ -128,7 +128,8 @@ namespace librbd {
     }
 
     ldout(cct, 20) << "detect format of " << name << " : "
-                  << (*old_format ? "old" : "new") << dendl;
+                  << (old_format ? (*old_format ? "old" : "new") :
+                      "don't care")  << dendl;
     return 0;
   }