segfault when clearing the messages vector

[sphaero]

Just testing the MidiIn example and added sending the messages vector through osc. Now running into segfaults when clearing the messages vector.

So receiving the messages like this

void newMidiMessage(ofxMidiMessage& msg)
    {
        midiMessages.push_back(msg);
        // remove any old messages if we have too many
        while(midiMessages.size() > maxMessages) {
            midiMessages.erase(midiMessages.begin());
        }
    }

But clearing the vector when they are send:

// clear captured midi messages
    std::vector<ofxMidiMessage>::iterator itr = midiIn.midiMessages.begin();
    while (itr != midiIn.midiMessages.end() )
    {
        itr = midiIn.midiMessages.erase(itr);
    }

(could also be midiIn.midiMessages.clear() )

However this segfaults on midiMessages.erase(midiMessages.begin()); which is puzzling unless this is happening in multiple threads?

Is the ofEvent originating from a different thread? Or any other ideas?

Rg,

Arnaud

[sphaero]

It does seem to be a threading issue. Adding mutex locks around the code modifying the midiMessages vector makes it stable!

[danomatika]

added sending the messages vector through osc.

Yes, this can happen if you start to have multiple threads involved, ie. MIDI and OSC receiver etc. I can add a note to the example about this.

[danomatika]

Ok, see e44c14a1fc76fe33786cb21f2fd908d0b4217605.