Export freezes in __search_from_socket

[huwpascoe]

Describe the bug
Exporting complicated materials with grouped nodes causes blender to freeze indefinitely.

Tracked it down to __search_from_socket, where the stack randomly goes up and down about 60 levels deep. I've managed to temporarily fix it with hack for my own personal use but this is obviously a serious bug that needs fixing.

.blend file/ .gltf (mandatory)
mrp.zip

Version
Windows 10
Blender 4.2

[julienduroure]

to freeze indefinitely.

Not really. Exported on 37.7s on my computer.

This is a duplicate of #2140 #2278

Root cause is a bad perf on bpy node.links iteration.

Probably the same issue (and same fix can be applied ?) than 35dd7f6