swizzling not supported on linux

[Raildex]

on Windows, the following compiles:

clipport.xy = glm::max(clipport.xy(), parent_vis.xy());
clipport.zw = glm::min(clipport.zw(), parent_vis.zw());

where clipport and parent_vis are vec4.

On linux, this does not work. it complains that you can't assignt to a function call.