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Re: Don't set DECL_IGNORED_P on a cdtor function

> So, I understand correctly, we're now going to again emit .debug_frame
> for DECL_IGNORED_P functions.  That seems good to me, as it helps us
> display unwind information through such functions.  I think that's a
> strong argument that we should always emit .debug_frame, independent of
> whether a function is ignored/artificial.


> There are 3 parts to the comment:
> 1. Setting breakpoints
> 2. Backtraces
> 3. Crashing
> Eric's patch solves (2).
> I don't think (1) or (3) are sufficient reasons to avoid setting
> DECL_IGNORED_P.  Almost all functions might crash (e.g., by extending
> the stack beyond the allocated maximum stack size) and *some* users
> might want to set breakpoints anywhere.  (Of course, they can always set
> a breakpoint by PC or by object-file symbol name anyhow.)
> The key issues are that (a) we have no source for these
> compiler-generated functions, and (b) they don't correspond to anything
> in the source program.  If I say "step" off the end of a C++ "main", I
> don't want to end up in one of these functions; I want to end up in the
> first C++ destructor being called by them.  That's the C++ view of the
> world; these cdtor functions are just implementation details.
> So, I think we should consider the issue closed, with Eric's patch.

Your comment seems to imply that Geoff's patch should be reverted too. :-)

Eric Botcazou

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