Re: [PR c++/20103] failure to gimplify constructors for addressabletypes

[Mark Mitchell <mark at codesourcery dot com>]

Alexandre Oliva wrote:
> > This doesn't look quite right.  First, we're trying to get rid of
> > tsubst_copy; we should not add new calls.  You should do the RECURs
> > here, and then build up the new node.
>
>
> I'd have to use build3 (TARGET_EXPR...) or introduce a new call to
> create a target_expr with given slot, initial and cleanup, because
> AFAICT there isn't any that takes a cleanup.

Yes, you should use build3.

> They don't, and they can't without this piece of code.  When we tsubst
> INITIAL, an incomplete array type (T[]), that had been used as the
> type of the slot and the target_expr itself in
> finish_compound_literal(), called while processing a template,
> digest_init() (or something else; I no longer remember exactly)
> completes the array type with the number of entries in the INITIAL
> CONSTRUCTOR.  

Then you should tsubst the INITIAL first, and unconditionally copy the 
type to the TARGET_EXPR when you use build3.  Or, even better, call the 
same functions in semantics.c that the parser would call if not in a 
template.  In other words, call finish_compound_literal again, from 
pt.c.  That's the overall design: we try to reuse the same semantic 
routines again at template instantiation time.

--
Mark Mitchell
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mark@codesourcery.com
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