[Bf-committers] Policies about patches modifying third-parties libraries.

[Bastien Montagne]

Hi,

Under build_files/build_environment/patches we have a bunch of small 
patches for the libraries we build using make deps. Most of them are 
about fixing builds for some platform or architecture, which is a bit 
annoying but acceptable imho.

However, today I discovered that Blender cannot be built with vanilla 
USD library, at all. The patch used on this library adds some new 
function to its API, which (hack over hack) is not even declared in its 
headers, but in Blender code itself.

I would very much like to propose to strictly forbid such dirty 
practices, which violate completely the very idea of libraries, 
especially on OSs like linux, where distributions try very hard to only 
use dynamically linked shared libraries.

Any library that would need that kind of modifications should be put in 
extern/, and explicitly built as part of Blender itself. Or at the very 
least, we should explicitly maintain our own 'fork' of it, with requests 
to the main repo/maintainers to integrate our changes or otherwise 
propose a solution to the problem.

But I do hope there are ways to avoid such ugly changes anyway?

Cheers,
Bastien