Do you need the vtable bug fixed?

[Martin v. Loewis]

As some of you know, there is an old bug in g++ involving virtual base
classes, and virtual function calls in constructors, on Linux
(i.e. with vtable thunks).

I have proposed a patch some months ago, and asked for inclusion of
this patch in gcc 2.95. This patch would fix the bug, at the expense
of binary compatibility: Code using the bug fix cannot be linked with
old code, anymore (in C++ applications where the bug potentially
occurs).

Therefore, this patch introduces the bug fix as an option: people that
need the bug fix can recompile everything with -fvtable-thunks=2. The
default would be the same as in egcs 1.1 (i.e vtable-thunks=1 on
Linux, no vtable-thunks elsewhere).

So far, the g++ maintainers have not decided whether to include that
fix or not. If people interested in that issue could speak up, maybe
that would help in finding a decision - if nobody is interested, this
would likely also help in finding a decision.

Regards,
Martin