[Bug c/105863] RFE: C23 #embed

["jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105863

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

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

--- Comment #7 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
_Embed opens the pandorra box what should happen when you stringify it or try
to token paste it together with something else etc.

Anyway, for GCC implementation of what C23 specifies, I wonder if we shouldn't
implement it in separate steps, first in a dumb way of just expanding it always
into preprocessor token, a path that could perhaps then be kept for the smaller
sizes when it isn't worth doing something smart.
And only in the second step try to add optimizations to it (guess for C those
could be easier than for C++ because C doesn't try to tokenize everything
first, so for C when we peek at the large embed token outside of the language
contexts where we know how to handle those (e.g. most importantly inside of
aggregate initializers) we could simply replace the token with expanded form of
it, say if one uses
void foo (...);
void bar ()
{
  foo (
#embed "foo_arguments"
  );
}
it would work without having to bother too much about that specific case.
The LLVM current pull request for this is
https://github.com/llvm/llvm-project/pull/68620
I think we should try to use same options where reasonable.