DTrace and clang -- ERROR: ctfmerge: kernel.debug: Cannot get sect .note.GNU-stack data

[Brandon Gooch]

On Dec 2, 2010, at 5:10 PM, Kostik Belousov <kostikbel at gmail.com> wrote:

> On Wed, Dec 01, 2010 at 11:48:10AM -0600, Brandon Gooch wrote:
>> I recently attempted to enable DTrace on a system running HEAD built
>> with clang, and saw this error scrolling by when the kernel and
>> modules were being built:
>> 
>> ERROR: ctfmerge: kernel.debug: Cannot get sect .note.GNU-stack data
>> 
>> Each module being built also displayed a similar message as to the above.
>> 
>> ERROR: ctfmerge: module_name: Cannot get sect .note.GNU-stack data
>> 
>> I've followed instructions here for building with clang:
>> 
>> http://wiki.freebsd.org/BuildingFreeBSDWithClang
>> 
>> ...and here for DTrace:
>> 
>> http://wiki.freebsd.org/DTrace
>> 
>> I've completed several rounds of building world and kernel from SVN
>> r216082 to r216095. Each time, it seems that kernel in world aren't
>> "in sync"
>> 
>> # netstat
>> netstat: no namelist
>> 
>> I can build the kernel using gcc, and DTrace (and netstat) output is
>> good. I haven't rebuilt world yet with gcc, as it takes a while, but
>> I'll certainly be doing that at some point I'm sure :)
>> 
>> Any debugging hints appreciated...
> 
> What is the revision of sources used to build the _installed_ version
> of libelf.so ? Make sure that it contains r210324.
> 
> I am unable to reproduce your problem with gcc/WITH_CTF=1, where gcc
> config is changed to emit .note.GNU-stack marker sections, similar to
> clang config.

I wasn't able to produce it using GCC either :)

I was informed that using DTrace with a clang-built system isn't supported.

-Brandon