Re: 7.7 Regression when loading a trace file

On 01/29/2014 09:59 PM, Marc Khouzam wrote:
> Hi guys,
> 
> sorry for the late message but I just noticed a regression with the proposed 7.7 when loading a tracefile.  The created inferior no longer has an execution (no pid, no thread), and no MI execution event is seen anymore (=thread-group-started or =thread-created).  So, I cannot load a trace file in Eclipse anymore.
> 

I had a change on this area

  [RFC] Don't create inferior in tfile target.
  https://sourceware.org/ml/gdb-patches/2013-05/msg00068.html

but not sure it is the causer.  I'll dig deep tomorrow.

What MI output is needed for Eclipse to load a trace file successfully?
=thread-group-started and =thread-created?

> 
> Broken session:
> 
>> gdb.7.7 -i mi ~/runtime-TestDSF/Producer/Debug/Producer
> =thread-group-added,id="i1"
> ~"GNU gdb (GDB) 7.7.50.20140128-cvs\n"
> (gdb) 
> target tfile /tmp/trace1
> &"target tfile /tmp/trace1\n"
> =tsv-created,name="trace_timestamp",initial="0"\n
> [...]
> 
> ========== no MI event about a process or thread  ================
> 

Since GDB opens a trace file, instead of a live inferior, it is
reasonable to me that no thread is created.

> ^done
> (gdb) 
> -list-thread-groups
> ^done,groups=[{id="i1",type="process",executable="/home/lmckhou/runtime-TestDSF/Producer/Debug/Producer"}]
> 
> ================= No pid field ======================

Likewise, it is reasonable to me that there is no pid field.

> 
> Working session:
> 
>> gdb.7.6 -i mi ~/runtime-TestDSF/Producer/Debug/Producer
> =thread-group-added,id="i1"
> ~"GNU gdb (GDB) 7.6.1\n"
> (gdb) 
> target tfile /tmp/trace
> &"target tfile /tmp/trace\n"
> =thread-group-started,id="i1",pid="1"
> =thread-created,id="1",group-id="i1"
> 
> ============= Notice the above two MI events ====================
> 
> =tsv-created,name="trace_timestamp",initial="0"\n
> ^done
> (gdb) 
> -list-thread-groups
> ^done,groups=[{id="i1",type="process",pid="1",executable="/home/lmckhou/runtime-TestDSF/Producer/Debug/Producer"}]
> 
> ============= Notice the pid field ==================
> 

-- 
Yao (齐尧)