[MPEG-OTSPEC] Some research on TT instructions and cubics

[Laurence Penney]

Is this a serious issue? Surely all binary formats have trillions of potential configurations of bits that do not conform to the spec. If your complaint is about the idea of undefined behaviour in a spec, then there are numerous instances of that would be up for discussion. If you want undefined behaviour to be replaced by insistence that a font should be rejected, then I think that goes against the ethos of many real-world font processors.

- Laurence

> On 23 Sep 2023, at 15:44, Jonathan Kew <jfkthame at gmail.com> wrote:
> 
> On 23/09/2023 15:26, Laurence Penney wrote:
>> Dear Hin-Tak,
>> Please review the official proposal document (not the .md file I referred to previously), in particular page 3, where the language used may be more to your liking ("must" means no need to speak of "undefined"):
> 
> But... page 3 there explicitly says: "If any of the conditions below are not met, the behavior is undefined."
> 
> JK
> 
>> https://github.com/harfbuzz/boring-expansion-spec/blob/main/iso_docs/WG03_otf-improvements.pdf
> 
>