[Bug libstdc++/69388] Allow functexcept.cc definitions to be replaced

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69388

--- Comment #3 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Following discussion with one of the libc++ developers, we're considering some
common API that would allow an aplication to globally turn those throws into
aborts, so that redefining them would be unnecessary.

One possibility is to link to some new lib (say, libnothrow.so) which would run
a static initializer or provide a definition for a weak symbol, causing the
__throw_xxx functions to unconditionally abort. That would not require a
special libstdc++ built without exceptions, and would mean that the choice is
fixed by the app at link-time (not dependent on which libstdc++.so happens to
be chosen by the dynamic linker, one that throws or one that aborts).