[Bug c++/84582] [8 Regression] Rejected valid C++ code since r257961

[jason at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84582

Jason Merrill <jason at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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                 CC|                            |jason at gcc dot gnu.org

--- Comment #5 from Jason Merrill <jason at gcc dot gnu.org> ---
(In reply to Jakub Jelinek from comment #2)
> Given:
> class C {
>   static const long b = 0;
>   static const unsigned c = (b);
> };
> class D {
>   static const long b = 0;
>   static const unsigned c = b;
> };
> template <class> class A {
>   static const long b = 0;
>   static const unsigned c = (b);
> };
> template <class> class B {
>   static const long b = 0;
>   static const unsigned c = b;
> };
> 
> we only reject the A case.
> For D and B there is just INTEGER_CST, and for C and A we have:
> (unsigned int) (long int) *(const long int &) &b
> because of the parens.
> The reason why it is accepted outside of template and not inside of it is
> that
> cxx_constant_init calls is_nondependent_static_init_expression which calls
> instantiation_dependent_expression_p and that is true in A::c.

Right, because &b is value-dependent.  I guess force_paren_expr can't do that
transformation in a template.