Where: trunk #417, Version 2.2.9.412.
Expression v1 = v2[v3] is not compiled, where v1, v2 and v3 are vectors with integers. But v2[v3] is correctly compiled to subvector construction involving type indexed_subvector which cannot be assigned to a vector due to lack of type classification in indexed_subvector definition.
Current workaround: v1 = v2.copy_subvector(v3);