Bug#809953: mathgl: FTBFS with libpng16

[tobi at debian.org]

Source: mathgl
Severity: important
User: libpng at packages.debian.org
Usertags: libpng16-transition

Dear mathgl maintainer,

Currently we are preparing the transistion of libpng1.2 to libpng1.6.
The transistion bug is #650601.

A rebuilt of all packages depending on libpng-dev and libpng12-dev
has been done. The result with buildlogs can be found here:
https://libpng.sviech.de/

mathgl FTBFS during this rebuild. The buildlog is available at
https://libpng.sviech.de/mathgl.build

The Titanpad at https://titanpad.com/libpng16-transistion might give
you clues about what went wrong as well as some recipes/pointers how
to fix them. Please feel free to amend the information on the pad as
you might see fit. A plain-text, non java-script version is here:
https://titanpad.com/ep/pad/export/libpng16-transistion/latest 

Please try to make mathgl compatible with libpng16 and then make sure
to B-D on libpng-dev only, if the fix makes it possible to compile it
against libdev12 and libdev16. If you can only make in a non-backward
compatible way, please B-D on libpng16-dev. 

This bug will become RC as soon as the transistion starts.

Best regards, 
-- 
tobi