crash in rav1e_config_unref() after upgrade from v0.5.1 to v0.6.3

[arancino1]

after upgrading from v0.5.1 to v0.6.3 the function rav1e_config_unref() crashes under Win10 64bit when called from C/C++ with an access violation reading at 0x03F. It doesn't matter if any encoding took place or not. Just creating a context with RaContext * ctx = rav1e_context_new(cfg); and any subsequent free via rav1e_config_unref(ctx); crashes.

No difference in rav1e.dll is delay loaded or LoadLibrary()/GetProcAddress() was being used.