This isn't a question but rather a quick report for my future reference - I
need to circle back and try to characterize this problem more fully when I'm
not on deadline and can run some additional tests with Boost 1.32.0.
Environment:
- MS 7.1 compiler w/their STL distribution
- Boost 1.31.0 (my client doesn't want to update to 1.32.0 until after this
release)
Summary:
boost::variant registered as an internal edge property map member on a BGL
graph causes the resultant graph to be inaccessible due to what appears to be
incorrect initialization of both the internal vertex and edge property maps.
I SUSPECT THAT THE ROOT CAUSE OF THIS CAN BE TRACKED BACK TO A MS 7.1
COMPILER BUG due to the fact that attempts to compile my test code results in
either of (a) an C1001 Internal Compiler Error (b) a error-free compile and a
completely screwed runtime.
Details:
The boost::variant in question is bounded by several unique specializations
of a fully-specialized class. As follows:
// pseudocode
class A;
class B;
class C;
template class edge_exeuctor
{};
template <> class edge_executor;
template <> class edge_exeuctor;
tempalte <> class edge_exeuctor;
template <> class edge_executor;
tempalte <> class edge_executor;
template <> class edge_executor;
typedef boost::variant<
edge_executor,
edge_executor,
edge_executor,
edge_executor,
edge_executor,
edge_executor > variant_edge_t;
The graph in question is declared as:
enum vertex_foo_property_t { vertex_foo_property = 801 };
enum edge_foo_property_t {edge_foo_property = 802 };
BOOST_INSTALL_PROPERTY(vertex, foo_property);
BOOST_INSTALL_PROPERTY(edge, foo_property);
typedef property > vertex_properties_t;
typedef property edge_properties_t;
typedef adjacency_list graph_t;
typedef graph_traits::edges_size_type edges_size_t;
Failure:
// THE TEST CODE WILL NOT ALWAYS COMPILE W/MS 7.1
// HALF THE TIME IT BOMBS W/C1001 INTERNAL COMPILER ERROR
// when it does compile, no errors are reported by the following runtime
behavior is observed
graph_t g;
edges_size_t edge_count = num_edges(g); // <- protection fault
// stepping into num_edges in a debug build reveals that both vertex and edge
property maps point to uninitialized memory (0xcdcdcdcd)
// removing variant_edge_t from edge_properties_t and replacing with an int
works as expected...
----
- Chris
