21.5/win32 + gnus

I get this really annoying bug in using Gnus under 21.5/win32_native: sometimes it ends up in executing execute_rare_opcode in src/bytecode.c, the opcode being null. This is trapped with an abort(). The problem is that: - I compiled xemacs/latest cvs in both optimized and debug mode, with no difference - I compiled gnus and have no shadows on my path except (build-report) - once gnus triggered this bug, I can't do nothing : it happens each time I try to restart it, just before redisplaying the Group buffer. For the moment, I have replaced the abort() in case of unknown opcode, with invalid_byte_code ("invalid opcode in instruction stream", make_int (opcode)); in the hop I could trap what triggers this annoying problem. Anybody with similar experience ? -- Fabrice