On Thu, 11 Jul 2019 at 00:39, Bryce Adelstein Lelbach aka wash
<brycelelbach_at_[hidden]> wrote:
>
> On Wed, Jul 10, 2019 at 12:09 PM Ville Voutilainen
> <ville.voutilainen_at_[hidden]> wrote:
> >
> > On Wed, 10 Jul 2019 at 22:06, Tom Honermann <tom_at_[hidden]> wrote:
> >
> > > You are implying that the include translation is mandatory. Is that your argument?
> > >
> > > Yes. The wording in [cpp.include]p7 seems fairly clear regarding that.
> >
> > Not at all. "If the header identified by the header-name denotes an
> > importable header" is implementation-defined. The set
> > of importable headers is allowed to be whatever the implementation
> > decides, including an empty set.
>
> Not exactly.
>
> http://eel.is/c++draft/module.import#5 says "A
> module-import-declaration that specifies a header-name H imports a
> synthesized header unit ..." and later "H shall identify an importable
> header."
>
> So H must be a part of that set of importable headers. Yes?

Well, if it's not, the program is ill-formed. Did you read
http://lists.isocpp.org/modules/2019/07/0490.php ?