On Mon, Nov 1, 2021 at 8:56 AM Aaron Ballman <aaron_at_[hidden]> wrote:

> On Fri, Oct 29, 2021 at 10:00 PM Hubert Tong via Liaison
> <liaison_at_[hidden]> wrote:
> >
> > It seems the C standard has a rule regarding the shift state of the
> spelling of string literals in the source file but neither the C standard
> nor the C++ standard specify what shift state should be observed just prior
> to the terminating NUL of a string literal. Is this lack of normative
> encouragement or requirement for the string to be in the initial shift
> state prior to the terminating NUL just a defect?
> >
> > Note that NUL is required by C to be encodable in any shift state;
> therefore, the need to insert NUL does not "naturally" cause strings in
> non-initial shift states to return to the initial shift state.
>
> I'm by no means an expert in this area, but does 5.2.1.2p1-2 cover this?
>
> 1 ...
> - A byte with all bits zero shall be interpreted as a null
> character independent of shift state. Such a byte shall not occur as
> part of any other multibyte character.
>
> 2 For source files, the following shall hold:
> - An identifier, comment, string literal, character constant, or
> header name shall begin and end in the initial shift state.
> ...
>
> So NUL is required to be interpreted regardless of shift state (per
> p1), and after the null, the string literal has to end in the initial
> shift state (per p2).
>

The shift state in the source has at most a tenuous relationship with the
shift state that would be observed in the contents of the string literal at
runtime.


>
> (Sorry if I'm misunderstanding something. This may also be worth
> asking on the SG16 mailing lists due to their expertise.)
>

I was hoping to get a comment from the C side as well.


>
> ~Aaron
>
>
>
>
> >
> > -- HT
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