#unordered_map find triggers Segment Fault

11 messages · Page 1 of 1 (latest)

obtuse marsh
#

I have the following class and when the schedule method tries to execute find, internally it reaches out to .empty method which triggers a Segment Fault error because of the inner current_sizevariable (debug view says: <read memory from 0xf0000000788 failed (0 of 8 bytes read)>):

template <std::size_t N>
using TimelineEvent = etl::vector<Event, N>;

template <std::size_t S, std::size_t N>
using Arrangement = etl::unordered_map<unsigned int, TimelineEvent<N>, S, S>;

template <std::size_t S, std::size_t N>
class Timeline
{
private:
    Transport* transport_;
    Arrangement<S, N> arrangement_;
    etl::deque<unsigned int, S> timeline_;

public:
    Timeline(Transport* transport) : transport_(transport), arrangement_() {}
    ~Timeline() = default;

    //copy
    Timeline(const Timeline&) = delete;
    Timeline& operator=(const Timeline&) = delete;

    // move
    Timeline(Timeline&&) = delete;
    Timeline& operator=(Timeline&&) = delete;

    void schedule(Event event)
    {
        if(arrangement_.find(event.time) != arrangement_.end())
        {
            arrangement_[event.time] = TimelineEvent<N>{event};

            auto it = etl::lower_bound(timeline_.begin(), timeline_.end(), event.time);

            timeline_.insert(it, event.time);
        }
    }
...

Usage example:

Timeline<4, 2> timeline{&transport};

timeline.schedule({{0, n8}, {0, n4}, {n4, n2}, {n2, n1}});

Any ideas why?

steady duneBOT
#

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knotty moth
#

I don't see current_size there.

obtuse marsh
#

current_size is a variable inside .empty which is part of the unordered_map implementation. .find uses .empty internally

south hatch
#

do you have a repo with some of this code in there? i was going to try to replicate it on my end until i noticed you're using non-STL containers (are those from the embedded template library?). if you can provide an easy way to run an example I can take a look to see if anything stands out.

obtuse marsh
#

Thanks for the help @south hatch . I've figured out that the problem was to due with my call to .schedule which should make use of etl::move (analogous to std::move). Unfortunately debugging only made it worse, since the stack trace pointed in a completely different direction.

steady duneBOT
#

@obtuse marsh Has your question been resolved? If so, type !solved :)

obtuse marsh
#

!solved

steady duneBOT
#

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south hatch