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get invalid pointer or invalid free() error when copying adjacency_matrix to a vector

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Dal 19/12/2022.

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Descrizione

data structure question

I have been trying to preload adjacency matrices with bundled properties to a std::vector of adjacency matrices in order to benchmark some uni project algorithm and not by chance measure the time to set up the graph.
In that instance i tried different approaches to copy a prototype g0:

  • std::fill wouldn't work as AM is not a value type.
  • boost::copy_graph() wouldn't work due to AM not being a list type
  • using std::vector::emplace to construct the graph in place using a constructor declared in the documentation and the AM.hpp: one (of 2) with the edge iterators and num_nodes. * Luckily boost::edges(graph_t) provides such a thing. But it wouldn't work as the edge-iterator-pair provided does not include a .first member. There is one that needs an a property iterator ep_it. i haven't found any information on how do make one and if this is meant for bundled properties.
  • using std::vector::push_back(g0) which works until the final "}" and then crashes when freeing or with a "munmap_chunk(): invalid pointer" error. g0 being a predefined graph i want to fill the vector with. It seems plausible as AM seems to be copy constructible. But apparently not entirely. Or maybe the property maps aren't.
    However: after running through the algorithms there seems to be no change to g0. So it does not seem to be a "shallow copy" problem. Also valgrind does not report any memory leaks. But lots of errors.
    This also happens when copy constructing only 2 graphs.
  • on a sidenote: the documentation for iterator constructible suggests passing the number of edges too as it may speed up some processes. The AM does not seem to provide such a thing in the documentation in the section member functions (i.e. constructors).
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