For locations inside the execution trace, the back trace is computed
based on the information stored in the execution trace.
+* New remote packets
+
+qXfer:btrace:read's annex
+ The qXfer:btrace:read packet supports a new annex 'delta' to read
+ branch trace incrementally.
+
*** Changes in GDB 7.7
* Improved support for process record-replay and reverse debugging on