free(): invalid pointer when using sorted query with std::list

[Simon PIERRE, EURODECISION]

Describe the bug
A memory corruption seems to occur when using sorted queries with std::list in any components.

To Reproduce

1. Compile the cpp/queries/sorting example with the first lines modified as follow

#include <sorting.h>
#include <iostream>
+#include <list>

struct Position {
    double x, y;
+    std::list<char> test;
};

// Order by x member of Position
int compare_position(
[...]

Expected behavior
The example compile and run just fine.

Current behavious

-- First iteration
{1,0}
{2,0}
{4,0}
{5,0}
{6,0}

-- Second iteration
{2,0}
{4,0}
{5,0}
{6,0}
{7,0}

-- System iteration
{2,0}
{3,0}
{4,0}
{5,0}
{6,0}
{7,0}
free(): invalid pointer
Aborted

Additional context

Compiled on windows WSL2 : g++ (Ubuntu 11.4.0-1ubuntu1~22.04) 11.4.0
Release and debug cause the same issue.

The list seems to be in a weird state in the destructor.

This is currently completely preventing me from used sorting. But otherwise thanks for the great work!

[Sander Mertens]

Fixed!