[Patch,fortran] Backtrace support (PR30498)

[Tobias Burnus]

Hi Paul,

Paul Thomas wrote:
> I dutifully did the patching and rebuilt my tree, only to get:
> Program received signal SIGSEGV: Segmentation fault.
> Backtrace for this error:
>  unable to produce a backtrace, sorry!
> So I seem to have tested three lines. *sigh*.  It looks nice but I can
> do nothing with it right now.
That's Cygwin, right? The implementation only works with GLIBC's
backtrace() function.
We should find out how we could offer something similar on other platforms.
Does MacOS has a glibc? Or do they use a different libc?

Tobias