Hi Mathieu, I know nothing about the topic and I probably out-of-scope. On Fri, 26 Feb 2021 at 15:14, Mathieu Othacehe wrote: > I'm trying to fix a memory corruption in the remote-server process of > Cuirass since a few days. Even though I don't have a usable core dump > file yet, I'm pretty sure the error comes from the "zmq-msg-init" > procedure of Guile-Simple-ZMQ. > > This procedure creates a bytevector, call the C function zmq_msg_init to > initialize it, adds zmq_msg_close as pointer finalizer and returns a > wrapped pointer. > > My understanding is that the wrapped pointer that is passed around in > Cuirass ensures that the underlying bytevector is not garbage collected > until the pointer goes out of scope. However, some assertions failures > such as this one: > > --8<---------------cut here---------------start------------->8--- > Assertion failed: check () (src/msg.cpp:394) > --8<---------------cut here---------------end--------------->8--- > > let me think that the bytevector is garbage collected, while ZMQ is > still using it. Some help would be much appreciated here :). From ’zmq-msg-init’ defined here: and why is ’zmq-message-content’ used for? Since ’message’ is initialized with zero, I guess. Well, I am confused by: --8<---------------cut here---------------start------------->8--- (let ((content-ptr (zmq_msg_data (message->pointer message))) [...] (pointer->bytevector content-ptr size)))) … (let ((msg (pointer->message! msg-pointer))) (when content-bv (let ((target (zmq-message-content msg))) (bytevector-copy! content-bv 0 target 0 len))) msg)))) --8<---------------cut here---------------end--------------->8--- Is ’target’ at the same address than ’msg’? Maybe ’target’ creates somehow a dangling pointer. Cheers, simon