Hello,
> > what exactly is the semantics of the cleanup for TARGET_EXPR?
> > Documentation says:
> >
> >
> >>Often, a @code{TARGET_EXPR} occurs on the right-hand side of an
> >>assignment, or as the second operand to a comma-expression which is
> >>itself the right-hand side of an assignment, etc. In this case, we say
> >>that the @code{TARGET_EXPR} is ``normal''; otherwise, we say it is
> >>``orphaned''.
> >
> > ...
> >
> >>If this expression is orphaned, then this expression must be executed
> >>when the statement containing this expression is complete.
> >
> >
> > What does "etc." in the definition of ``normal'' mean? Is say target_expr
> > in
> >
> > a = b ? TARGET_EXPR : something;
> >
> > orphaned? If TARGET_EXPR is not orphaned, is it allowed to run its cleanup?
>
> That should be considered a "normal" use, just like "a = TARGET_EXPR".
>
> In the abstract, the best thing might be for there to be a TARGET_EXPR
> around the entire COND_EXPR, but IIRC, the way it works is that there
> will be a TARGET_EXPR for each arm of the conditional. Here, the
> cleanups should not be run. However, if it were just "b ? TARGET_EXPR :
> something", then the cleanups should be run; that would be an orphaned use.
umm... OK. Could you please provide an example (that could perhaps also
be added to documentation) of how TARGET_EXPRs are used, that would
explain the rationale behind this semantics?
Zdenek
