(*foo)[index] = bar;

foo->insert(std::pair<KeyType,ValueType>(myKey, myValue));

...
typedef std::map<int, SCNode*> SCNodeMap;
...


void StemAndCycle::getCycleNodes(SCNodeMap* cycleNodes)
{
    (*cycleNodes)[root->getId()] = root;

    SCNode* tmp = root->getSucc();
    while(tmp->getId() != root->getId())
    {
        // (*cycleNodes)[tmp->getId()] == tmp; // crashes (in loop below)
        cycleNodes->insert(std::pair<int, SCNode*>(tmp->getId(), tmp));//OK
        std::pair<int, SCNode*> it = *(cycleNodes->find(tmp->getId()));
        tmp = tmp->getSucc();
    }

    // debugging; print ids of all the SCNode objects in the collection
    std::map<int, SCNode*>::iterator it = cycleNodes->begin();
    while(it != cycleNodes->end())
    {
        std::pair<int, SCNode*> p = (*it);
        SCNode* tmp = (*it).second; // null except for it = cycleNodes->begin()
        std::cout << "tmp node id: "<<tmp->getId()<<std::endl;
        it++;
    }

}

(*cycleNodes)[tmp->getId()] == tmp;

(*cycleNodes)[tmp->getId()] = tmp;

if ( amap[x] == 42 ) {
   ...
}