Re: [Libunwind-devel] Build glibc linking libunwind

[Paul Pluzhnikov]

On Wed, Oct 12, 2011 at 4:14 AM, Ken Werner <address@hidden> wrote:
> On 09/24/2011 11:46 PM, Fabio wrote:
>>
>> Hi all,
>> I am trying to build glibc and link libunwind to get a backtrace at
>> the beginning of some glibc function like strcpy for example but I
>> can't get them to build.
>> I include -lunwind in the CFLAGS and I export
>> LD_LIBRARY_PATH=/usr/local/lib, but when it comes to build ld.so it
>> fails:
>>
>> /home/wintermute/tesi/glibc/2.14/custom/glibc-2.14/string/strcpy.c:43:
>> undefined reference to `_Ux86_getcontext'
>> /home/wintermute/tesi/glibc/2.14/custom/glibc-2.14/string/strcpy.c:44:
>> undefined reference to `_ULx86_init_local'
>> collect2: ld returned 1 exit status
>>
>> Am I missing something? Sorry for asking a dumb question and thanks in
>> advance.
>
> I suspect you're on a system where the linker does not pull in indirect
> shared libs (the default behavior of recent Debian or Fedora based distros).
> I had a similar issue - see:
> http://lists.gnu.org/archive/html/libunwind-devel/2011-03/msg00002.html.
> You're probably just missing to link against libunwind-x86_64.so. Adding
> -lunwind-x86 to your CLFAGS/LDFLAGS should be sufficient.

The link failure is while linking ld.so itself. It better not use
libunwind-x86_64.so (or any other shared library) for obvious reasons.


-- 
Paul Pluzhnikov