segfault when copying btGimpactMeshShape

[mqnc]

I've been bitten by the following simplified code:

#include <BulletCollision/CollisionShapes/btTriangleMesh.h>
#include <BulletCollision/Gimpact/btGImpactShape.h>

int main()
{
    btTriangleMesh mesh = btTriangleMesh();

    mesh.addTriangle(
        btVector3(1, 0, 0),
        btVector3(0, 1, 0),
        btVector3(0, 0, 1)
	);
 
    btGImpactMeshShape gimpactShape = btGImpactMeshShape(&mesh);
    gimpactShape.updateBound();

    btGImpactMeshShape gimpactShape2 = btGImpactMeshShape(gimpactShape);
    gimpactShape2.updateBound();

    return 0;
}

This is because the implicit copy constructor just copies m_mesh_parts and the parts then get deleted twice upon destruction. Providing an explicit copy constructor solves this issue:

btGImpactMeshShape(const btGImpactMeshShape& other): btGImpactShapeInterface(other)
{
	m_meshInterface = other.m_meshInterface;
	//m_mesh_parts = other.m_mesh_parts; // this is what the implicit copy ctor does which causes the segfault
	buildMeshParts(m_meshInterface);
}

However, I haven't found many copy ctors throughout the code... Is there some agreement that shapes shouldn't be copied? Could we at least delete the default copy constructor?