[luatex] What happens to glyphs not in the font?

[Taco Hoekwater]

Hi,

On 25 Mar 2014, at 23:32, Arno Trautmann <Arno.Trautmann at gmx.de> wrote:

> Martin Schröder wrote:
>> 2014-03-25 22:12 GMT+01:00 Arno Trautmann <Arno.Trautmann at gmx.de>:
>>> Martin Schröder wrote:
>>>> I'd expect
>>>> Missing character: There is no � in font cmr10!
>>>> (maybe even with an "ß" :)
>>> 
>>> Well – no. The minimal example I posted compiles just fine, neither a
>>> warning or an error. (With an “eszett” in case it was broken by my mail
>>> client?)
>> 
>> Yes, but that's clearly a bug.
> 
> oh … I thought it was a feature. Same happens with pdfTeX, btw.

In pdftex you probably see nothing because it depends on the setting of
\tracinglostchars. In luatex, there was a bug, where nothing was ever
printed except in some odd cases inside math and the virtual font definition
processing.
 
I’ve committed a fix that checks during shipout and,  with \tracinglostchars=2, 
I now get this output on the terminal:

  [1{/Users/taco/context/tex/texmf/fonts/map/pdftex/plain/pdftex.map}
  Missing character: There is no ß (U+00DF) in font cmr10!
  ]

that is not completely perfectly right, because it is not really a character at 
that point, but that is mostly cosmetics, and this message is a bit easier to
comprehend than ‘Missing glyph’.

Best wishes,
Taco