On Thu, 24 Mar 2005 11:29:09 -0800, Mark Mitchell <[EMAIL PROTECTED]> wrote:
19317 C++ problems with temporary return values
This patch breaks Qt builds. One of my patches is implicated, but I believe that the consensus is that this is an NRV bug. Jason made several attempts at fixing this. Does anyone know what the current status is?
Basically, the problem is that the return slot optimization in expand_call is incompatible with the NRVO; if the callee shares the return slot with a variable, the caller can't share it with an object which escapes. expand_call has no way of checking whether "target" escapes, so I think we probably just need to disable the optimization there.
I agree that now is not the time for heroic fixes. Would you be willing to work up a patch to disable the expand_call optimization?
Thanks,
-- Mark Mitchell CodeSourcery, LLC [EMAIL PROTECTED] (916) 791-8304
