Unexpected negative edge weight error in boost::prim_minimum_spanning_tree

Question

The following code throws "negative edge weight" on prim_minimum_spanning_treecall even though i am using only positive numbers. What should be changed to make it work?

typedef boost::property<vertex_distance_t, int> VertexProperty;
typedef boost::property<edge_weight_t, int> EdgeProperty;
typedef adjacency_list<vecS, vecS, undirectedS, VertexProperty, EdgeProperty> Graph;

typedef pair<int, int> Edge;

Edge edges[] =      {Edge(0, 1), Edge(1, 2)};
int weights[] =     {2, 1}; // this works: int weights[] =   {1, 2}; 

Graph g(edges, edges + sizeof(edges)/sizeof(Edge), weights, 3);
std::vector<Graph::vertex_descriptor> predecessors(num_vertices(g));
boost::prim_minimum_spanning_tree(g, &predecessors[0]);

Note: I can make it succeed by tweaking weight values.

Compiler : MS Visual Studio 2010 C++ Boost version: 1.54

Answer 1

This was a Boost bug, and is already fixed: if anyone else sees this behavior from 1.54, just update to 1.55 or newer.