UST integration is broken

UST integration is broken

[Sergio Durigan Junior]

Hello,

I am working on something related to static tracepoints markers, which
is related to UST (http://lttng.org/ust).  I did some modifications on
the code, and was trying to test the result, when I realized I did not
have UST installed here.  Ok, so I decided to compile it and install
locally just for a quick test, and after some time struggling with
compilation flags, I noticed that the current UST does not support GDB
anymore.  For more information, see this commit:

http://git.lttng.org/?p=ust.git;a=commit;h=fe566790e6be3f27f0befd85b715a3e84977bf6c

I also noticed that the header file ust/ust.h is not installed, thus
making the configure process useless.  I am sending this message because
I am in doubt about what to do: should we completely remove the support
from GDB (since according to the commit message above, the
implementation is going to be revamp'ed), or just temporarily disable
it?  I was going to send a patch for the latter, but decided to ask
first.

Thanks,

Sergio.

Re: UST integration is broken

[Sergio Durigan Junior]

Sergio Durigan Junior <sergiodj@redhat.com> writes:

> I also noticed that the header file ust/ust.h is not installed, thus
> making the configure process useless.  I am sending this message because
> I am in doubt about what to do: should we completely remove the support
> from GDB (since according to the commit message above, the
> implementation is going to be revamp'ed), or just temporarily disable
> it?  I was going to send a patch for the latter, but decided to ask
> first.

Or we could just check for the UST version, and not compile if it is
greater than XYZ.

Re: UST integration is broken

[Tom Tromey]

>>>>> "Sergio" == Sergio Durigan Junior <sergiodj@redhat.com> writes:

Sergio> I also noticed that the header file ust/ust.h is not installed, thus
Sergio> making the configure process useless.  I am sending this message because
Sergio> I am in doubt about what to do: should we completely remove the support
Sergio> from GDB (since according to the commit message above, the
Sergio> implementation is going to be revamp'ed), or just temporarily disable
Sergio> it?  I was going to send a patch for the latter, but decided to ask
Sergio> first.

I would just leave things as they are.  When UST starts using the SDT
probes, we can revisit the situation.

Meanwhile, for your testing, I would just use an older version of UST.

Tom

Re: UST integration is broken

[Yao Qi]

On 01/07/2012 10:37 AM, Sergio Durigan Junior wrote:
> I am working on something related to static tracepoints markers, which
> is related to UST (http://lttng.org/ust).  I did some modifications on
> the code, and was trying to test the result, when I realized I did not
> have UST installed here.  Ok, so I decided to compile it and install
> locally just for a quick test, and after some time struggling with
> compilation flags, I noticed that the current UST does not support GDB
> anymore.  For more information, see this commit:
> 
> http://git.lttng.org/?p=ust.git;a=commit;h=fe566790e6be3f27f0befd85b715a3e84977bf6c
> 

libinproctrace.so is unable to build with UST after 0.11
release.  GDB support in UST was temporarily removed from UST by the
commit you pointed out.  GDB CVS trunk is still able to build with UST
0.11 and URCU 0.5.3.

> I also noticed that the header file ust/ust.h is not installed, thus
> making the configure process useless.  I am sending this message because
> I am in doubt about what to do: should we completely remove the support
> from GDB (since according to the commit message above, the
> implementation is going to be revamp'ed), or just temporarily disable
> it?  I was going to send a patch for the latter, but decided to ask
> first.

If UST 0.11 is installed, everything still works well, otherwise, UST
stuff will not be compiled.  So I disagree to disable it temporarily.

There has been a PR for this issue,

  gdb 7.2 can't build with lttng-ust 0.12
  http://sourceware.org/bugzilla/show_bug.cgi?id=12699

-- 
Yao (齐尧)