[Windows] Fix windows build with mingw.

Forces ".dll" extension for library when building with mingw.

Override GDN_EXPORT which is incorrectly defined in the upstream
gdnative headers (3.x) and godot-cpp include (4.0) when building for
windows with mingw.

1 files changed, 6 insertions, 0 deletions

diff --git a/src/init_gdextension.cpp b/src/init_gdextension.cpp
index c923881..b252379 100644
--- a/src/init_gdextension.cpp
+++ b/src/init_gdextension.cpp
@@ -37,6 +37,12 @@
 #include "WebRTCLibDataChannel.hpp"
 #include "WebRTCLibPeerConnection.hpp"
 
+#ifdef _WIN32
+// See upstream godot-cpp GH-771.
+#undef GDN_EXPORT
+#define GDN_EXPORT __declspec(dllexport)
+#endif
+
 using namespace godot;
 using namespace godot_webrtc;