[Rcpp-devel] (Very) rare segfault

[Gregor Kastner]

Thanks to all three of you for your blazing responses.

> | 1. Try running the code with `gctortue(TRUE)` on,

Currently running. Extrapolating from the performance I see now I expect the
bug to reappear in <10 years...

> | 2. Try running with a debugger (gdb, lldb, valgrind),
> | 3. Try running with sanitizers (see e.g. Dirk's docker
> containers: https:// | github.com/eddelbuettel/docker-ubuntu-r)
> 
> 3.b  Also https://github.com/eddelbuettel/docker-debian-r with newer
> compilers 
> | This should help provide you (and/or us) enough information to diagnose
> the | problem.

That requires a bit more studying on my side; I'll get to that immediately
after finishing those 3 open papers :)

> Moonshoot:  Do you by chance insert RNGScope instances?  We have at times
> have had issues with their handshaking of state back to R, temp objects etc
> pp.

Alas, magician! Indeed, removing the "RNGScope scope;" line seems to put and
end to the weirdness. I guess I'll rely on the seed being set in R for now.

BTW, I can now confirm that the issue appeared during the transition from
0.10.6 to 0.11.0.

I really hope to be able to provide some more information some time soon.

Thanks for now,
Gregor