[XeTeX] handling malformed UTF-8 input

[Taco Hoekwater]

Will Robertson wrote:
> On 21/02/2008, at 8:42 PM, Jonathan Kew wrote:
> 
>> What do others think about this -- should "invalid UTF-8 byte
>> sequence" be an error rather than a warning and fallback?

In such cases, luatex gives a "... contains an invalid utf-8 sequence"
error, replaces the culprit with U+FFFD, and continues hoping
to find proper utf-8 from then on.

Luatex doesn't have a "byte" mode, so it can't fallback to that,
not even if it wanted to. (but I don't. I am happily generating
so many errors that users will be very likely abort the run and
fix the file).

Best wishes,
Taco