How to fix error "ERROR: godot_nativescript_register_property: Attempted to register method on non-existent class."?

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:bust_in_silhouette: Asked By Robotex

I’m using GDNative script and I see this error messages at game start.

ERROR: godot_nativescript_register_property: Attempted to register method on non-existent class.
   At: modules/gdnative/nativescript/godot_nativescript.cpp:122.
ERROR: godot_nativescript_register_property: Attempted to register method on non-existent class.
   At: modules/gdnative/nativescript/godot_nativescript.cpp:122.
ERROR: godot_nativescript_register_property: Attempted to register method on non-existent class.
   At: modules/gdnative/nativescript/godot_nativescript.cpp:122.
ERROR: godot_nativescript_register_property: Attempted to register method on non-existent class.
   At: modules/gdnative/nativescript/godot_nativescript.cpp:122.

and at the end:

ERROR: get_symbol: No valid library handle, can't get symbol from GDNative object
   At: modules/gdnative/gdnative.cpp:501.
ERROR: terminate: No valid library handle, can't terminate GDNative object
   At: modules/gdnative/gdnative.cpp:406.

What does it mean? What is wrong?

:bust_in_silhouette: Reply From: sash-rc

All these messages are very generic.
The most meaningful (No valid library handle) says by some reason a library not found (by godot) or it is not properly configured.

Yes, I’m making that library. I need to fix it.

Robotex | 2020-12-06 17:46

Yes, exactly so.

sash-rc | 2020-12-07 10:02

Are you kidding me?

Robotex | 2020-12-10 17:24