Repository navigation
Collision on CONNECT_DEFERRED #1935
Description
Godot version
4.5
godot-cpp version
4.5
System information
Windows 11
Issue description
The Windows SDK defines CONNECT_DEFERRED as a hex value with a preprocessor statement in winnetwk.h. However, Godot’s Object class uses it as an enum value name inside ConnectFlags.
A fix is present inside godot_cpp/core/defs.hpp:
#undef CONNECT_DEFERRED // override from Windows SDK, clashes with Object enum
The issue is that the header is #pragma once, meaning that if defs.hpp is ever included before the Windows SDK, the fix stops working because the header can't be included again. In a large codebase, making sure that the right include order is respected everywhere is a very complex task.
A way to make this fix more reliable would be to move the #undef statements inside defs.hpp to another header that doesn't have a #pragma once directive. They are already guarded by #ifdef clauses, so this should be okay in theory.
Steps to reproduce
- Include any Godot header that has
godot_cpp/core/defs.hppin its include chain - Include
Windows.h - Include
godot_cpp/core/defs.hpp - Try to use
CONNECT_DEFERRED: Windows's define hasn't been undefined bydefs.hpp
Minimal reproduction project
Compile with scons, the following errors are thrown:
- 'constant': illegal token on right side of '::'
- type 'unknown-type' unexpected
See src\example_class.h for the problematic code and explanation comments.
Activity
dsnopek commentedon Feb 23, 2026
Thanks for the report!
I'm not sure this is something we can fully handle on the godot-cpp side, since godot-cpp isn't the one including
windows.h. If someone builds a GDExtension and they are includingwindows.h, I think the only fully reliable fix is making surewindows.his included before any godot-cpp headers. We could consider switchingdefs.hppback from#pragma onceto using header guards (and maybe put the#undefoutside of them), but that'll only improve things in a couple situations, not all of them