[cairo] Issue with Cairo Font Cache

[Lawrence D'Oliveiro]

On Wed, 18 Mar 2015 16:44:41 -0400, Jian Ye wrote:

>> Are you doing the user_data dance as documented here
>> <http://cairographics.org/manual/cairo-FreeType-Fonts.html#cairo-ft-font-face-create-for-ft-face>?
>
> No I didn't do it.

You must. And remember that, as a result of that, Cairo has stolen the
reference to the FT_Face (which it will dispose of with FT_Done_Face
that you gave it to call when it is done). So if you want to keep
working with the same FT_Face object, you must call FT_Reference_Face
on it to get your own reference (and balance that with your own call to
FT_Done_Face when you are done).