On 6/18/26 5:15 PM, Jakub Jelinek wrote:
On Thu, Jun 18, 2026 at 04:37:44PM -0400, Jason Merrill wrote:
On 6/18/26 3:20 PM, Marek Polacek wrote:
Currently, we include all the built-ins like __builtin_fdimf32x in
the result of members_of. We probably should skip them. This patch
uses DECL_IS_UNDECLARED_BUILTIN so that we skip __builtin_abs but
include abs.
On ^^:: this reduces the # of elements from 2591 to 653.
PR c++/125819
gcc/cp/ChangeLog:
* reflect.cc (namespace_members_of): Skip
DECL_IS_UNDECLARED_BUILTIN functions.
Why only functions? I'd think we want to skip all kinds of built-in decls.
I think it would be weird if builtins are hidden from members_of (sure, the
__integer_pack can be an exception), users can use say
decltype (::__builtin_fdimf32x) etc. too, so why should we hide them from
users during reflection through which they can query them similarly?
I expect people to use reflection to ask about the contents of the
program rather than the compiler; for the latter there is __has_builtin.
And as you mention in your followup, a lot of the built-ins don't play
well with the C++ type system. It seems to me most consistent to just
exclude them from members_of.
I also don't expect people to use explicit :: when naming a built-in.
Jason
