Rémi Bernon (@rbernon) commented about include/appnotify.h:
+#include <windows.h>
+#ifdef _CONTRACT_GEN +#define PSM_APP_API_HOST +#endif
+#ifdef __cplusplus +extern "C" { +#endif
+#if defined(PSM_APP_API_HOST) +#define APICONTRACT +#else +#define APICONTRACT DECLSPEC_IMPORT +#endif
As you're never defining _CONTRACT_GEN, this will always expand to DECLSPEC_IMPORT, which I think is wrong within the twinapi.appcore module.
You should add `EXTRADEFS = -D_CONTRACT_GEN` in its Makefile.in.