On Wed, Nov 23, 2016 at 11:36 AM, Jakub Jelinek <ja...@redhat.com> wrote:
> On Wed, Nov 23, 2016 at 10:42:57AM -0500, Jason Merrill wrote:
>> OK, but I wonder why we don't do constant initialization of that variable...
>
> Dunno either, check_initializer simply returns the call to the constructor
> for the var. I've tried something like:
>
> --- gcc/cp/decl.c.jj 2016-11-21 19:47:06.000000000 +0100
> +++ gcc/cp/decl.c 2016-11-23 17:31:15.963594787 +0100
> @@ -6339,7 +6339,27 @@ check_initializer (tree decl, tree init,
> init_code = NULL_TREE;
> }
> else
> - init = NULL_TREE;
> + {
> + init = NULL_TREE;
> + if (TREE_CODE (init_code) == CALL_EXPR)
> + {
> + tree callee = get_callee_fndecl (init_code);
> + /* If INIT_CODE is a call to constexpr ctor,
> + see if we can optimize it into a constant
> + initialization. */
> + if (callee
> + && DECL_DECLARED_CONSTEXPR_P (callee)
> + && DECL_CONSTRUCTOR_P (callee)
> + && !flag_no_inline)
> + {
> + init = maybe_constant_value (init_code);
> + if (TREE_CODE (init) == CALL_EXPR)
> + init = NULL_TREE;
> + else
> + init_code = NULL_TREE;
> + }
> + }
> + }
> }
>
> if (init && TREE_CODE (init) != TREE_VEC)
>
> but store_init_value still doesn't like that and turns it into a runtime
> initialization.
>
> So, shall I check the patch in and defer the rest to you, or just defer it?
Go ahead and check it in.
Jason
