boost::polygon::operators::operator* crashes on a specific pair of polygons

[ckozhukhin@…]

The issue appears to be caused by int overflow - if I halve the value of coordinates of both polygons operator* works correctly.

Polygon1: (-2147483646, -2147483646), (429496729, -2147483646), (2147483646, 2147483646)

Polygon2: (-1288490188, -2147483646), (1288490188, -2147483646), (1288490188, 2147483646), (-1288490188, 2147483646)

Code snippet:

namespace bp = boost::polygon;
using namespace boost::polygon::operators;

typedef bp::polygon_data<int> Polygon;
typedef bp::polygon_traits<Polygon>::point_type Point;
typedef std::vector<Polygon> PolygonSet;

...

Polygon p1 = makeBoostPolygon(...);
Polygon p2 = makeBoostPolygon(...);
PolygonSet ps1;
ps1 += p1;
PolygonSet ps2;
ps2 += p2;
PolygonSet intersection;
assign(intersection, ps1*ps2); // Crashes with access violation

[Constantine Kozhukhin <ckozhukhin@…>]

Forgot to mention - I observed the crash on Windows x64 in Visual Studio 2010 Express.

[Andrii Sydorchuk]

Hi,

Thanks for the report. If possible, could you attach the full code snippet or file?

Thanks, Andrii

[ckozhukhin@…]

Crash reproducer

[ckozhukhin@…]

Andrii, I attached VC++ project with the reproducer. I used VS 2010 Express. In Debug configuration it triggers a debug assertion in line 45

	ps1 += p1;

[Andrii Sydorchuk]

The issue was related to the integer overflow. I've fixed the problem. Please apply the attached patch or sync with the trunk branch: ​https://svn.boost.org/svn/boost/trunk/boost/polygon/