Assertion failed when trying to add system

[smarchevsky]

#include <entityx/entityx.h>

#include <iostream>
#include <cassert>

namespace ex = entityx;
using namespace std;
struct vec2 {
    float x, y;
    vec2(float x, float y) : x(x), y(y) {}
    vec2() : x(0), y(0) {}
    vec2 operator+(const vec2 &v) { return vec2(x + v.x, y + v.y); }
    vec2 &operator+=(const vec2 &v) { return *this = *this + v; }
    void log() { std::cout << x << " " << y << std::endl; }
};
struct Position : vec2 {
    Position() {}
    Position(float x, float y) : vec2(x, y) {}
};

struct Direction : vec2 {
    Direction() {}
    Direction(float x, float y) : vec2(x, y) {}
};

struct MovementSystem : public ex::System<MovementSystem> {
    void update(entityx::EntityManager &es, entityx::EventManager &events, ex::TimeDelta dt) override {
        const float fdt = static_cast<float>(dt);
        es.each<Position, Direction>([fdt](ex::Entity entity, Position &pos, Direction &dir) {
            pos.x += dir.x * fdt;
            pos.y += dir.y * fdt;
        });
    }
};

int main() {
    entityx::EntityX world;
    world.systems.add<MovementSystem>();
    world.systems.configure();
    world.systems.update<MovementSystem>(1.2);
    entityx::Entity entity = world.entities.create();
    entity.assign<Position>(1.0f, 2.0f);
    entity.assign<Direction>(1.0f, 2.0f);
}

When add line "world.systems.add();" - I receive a runtime assert:

CppTest: malloc.c:2401: sysmalloc: Assertion `(old_top == initial_top (av) && old_size == 0) || ((unsigned long) (old_size) >= MINSIZE && prev_inuse (old_top) && ((unsigned long) old_end & (pagesize - 1)) == 0)' failed. The program has unexpectedly finished.

[alecthomas]

What OS/compiler/versions?

[smarchevsky]

Sorry, I just noticed while debugging. I linked Anax and EntityX in one project. Just did it to try different ECS. Breakpoint moved to Anax headers.

[alecthomas]

Ok.