On Tue, May 28, 2019 at 10:07:12AM -0400, Jason Merrill wrote:
> > "or captures a structured binding (explicitly or implicitly), the program is
> > ill-formed."
> > Is P0588R1 a DR that would be applied to older standards?
>
> P0588 was certainly intended to apply to C++17, but I'd treat this as
> overriding it, and not complain.
Ok.
> > --- gcc/cp/decl.c.jj 2019-05-20 14:52:26.871375569 +0200
> > +++ gcc/cp/decl.c 2019-05-20 15:48:33.563599150 +0200
> > + && (DECL_NAMESPACE_SCOPE_P (decl) || TREE_STATIC (decl)))
> > + if (TREE_STATIC (v[i]))
>
> When can a structured binding not be TREE_STATIC?
All the block scope structured bindings that aren't explicitly static
nor thread_local are not TREE_STATIC, and we really can't mangle them (and
cp_maybe_mangle_decomp is called on them). And newly we need to mangle
even block scope structured bindings that are static or thread_local.
As extern isn't allowed (yet), perhaps all DECL_NAMESPACE_SCOPE_P (decl)
structured bindings are TREE_STATIC and I could replace the
DECL_NAMESPACE_SCOPE_P (decl) test in cp_maybe_mangle_decomp
with TREE_STATIC (decl) instead.
Jakub
