Re: [patch] Support C++11 rvalue (move constructor)

[Tom Tromey <tromey@redhat.com>]

CCing Jonathan Wakely.

Jan> currently one cannot debug C++11 move constructors, one gets:

This is PR 14441.  Also see the thread:
https://sourceware.org/ml/gdb/2012-10/msg00108.html

I think Jonathan started a branch for this...

Jan> Therefore there is a KFAIL in the testcase for it.  I do not think
Jan> GDB needs to handle && differently - except for displaying &&
Jan> instead of &.

Is that also true for inferior calls?
I didn't look.

Jan>     or to add new main_type::flag_ref_is_rvalue valid only for
Jan>     TYPE_CODE_REF but that is sure not a clean implementation.

If the semantics of the two kinds of references are sufficiently
similar, then I don't think it is actually so bad.

Jan> (2) One would need to add type.rvalue_reference_type (besides
Jan> type.reference_type) to prevent leaks of types.  This would mean
Jan> increasing the current sizeof (struct type) 40 -> 48.  The proper
Jan> solution is to rather implement reference counting or garbage
Jan> collecting of types and merge struct type into struct main_type.

Maybe the size increase isn't that important.
Alternatively maybe it can be handled like qualifiers.

Jan> Anyway currently I find the patch below as a good enough hack as currently
Jan> I find it a bit blocker when using C++11.

It seems reasonable to me -- an improvement, and not blocking any future
improvements.

Tom