[PATCH][_GLIBCXX_DEBUG] libbacktrace integration

[François Dumont]

On 07/05/21 4:26 pm, Jonathan Wakely wrote:
> On 05/05/21 12:33 +0100, Jonathan Wakely wrote:
>> On 24/04/21 15:46 +0200, François Dumont via Libstdc++ wrote:
>>> Hi
>>>
>>>     Here is the patch to add backtrace generation on _GLIBCXX_DEBUG 
>>> assertions thanks to libbacktrace.
>
> Ville pointed out that we'll need to use libbacktrace for
> std::stacktrace <https://wg21.link/P0881R7> anyway, and it would be
> useful if/when we add support for C++ Contracts to the lirbary.
>
> So let's integrate libbacktrace into libstdc++ properly. Jakub
> suggested doing it how libsanitizer does it, which is to rebuild the
> libbacktrace sources as part of the libsanitizer build, using the
> preprocessor to rename the symbols so that they use reserved names.
> e.g. rename backtrace_full to __glibcxx_backtrace_full or something
> like that.
>
> I'll work on getting it building as part of libstdc++ (or maybe as a
> separate static library for now, as we do for libstdc++fs.a) and then
> you can rework your Debug Mode patch to depend on the private version
> of libbacktrace included with libstdc++ (instead of expecting users to
> provide it themselves).
>
Ok, thanks for the info.

I will perhaps extract the non-backtrace related stuff from this patch 
then and I'll rework the backtrace part later.