vrp functions crash server

[cvvergara]

Problem

Server crash

To Reproduce

I was experimenting with what would happen if the code of the vrp functions were executed from a different extension name, this experiment is to look forward to move the vrp functions to a public different repository
So, I created a pgRouting extension and a vrpRouting extension with exactly the same code of pgRouting
and on the vrpRouting extension I ran:

PREPARE No_problem_query AS
SELECT * FROM vrp_pickDeliver(
    $$ SELECT * FROM orders ORDER BY id $$,
    $$ SELECT * FROM vehicles ORDER BY id$$,
    $$ SELECT * FROM pgr_dijkstraCostMatrix(
        'SELECT * FROM edge_table ',
        (SELECT array_agg(id) FROM (SELECT p_node_id AS id FROM orders
        UNION
        SELECT d_node_id FROM orders
        UNION
        SELECT start_node_id FROM vehicles) a),
        directed => false)
    $$
);

this is combines pgRouting and vrpRouting

SELECT * FROM vrp_pickDeliver(
...
$$ SELECT * FROM pgr_dijkstraCostMatrix(
...

Which generated a server crash.
The way it generated the server crash was as follows:
For simplification:
pgtap test = pgtap test with one or more queries that combines the 2 extensions
test = a pgtap test can have or can not have a query that combines the 2 extensions
Ran a pgtap test without problems, but when the next test started the server crash happened.

2021-01-17 09:05:24.776 CST [15181] HINT:  In a moment you should be able to reconnect to the database and repeat your command.
2021-01-17 09:05:24.777 CST [19237] vicky@pgr_test__db__test WARNING:  terminating connection because of crash of another server process
2021-01-17 09:05:24.777 CST [19237] vicky@pgr_test__db__test DETAIL:  The postmaster has commanded this server process to roll back the current transaction and exit, because another server process exited abnormally and possibly corrupted shared memory.
2021-01-17 09:05:24.777 CST [19237] vicky@pgr_test__db__test HINT:  In a moment you should be able to reconnect to the database and repeat your command.

Expectation

No server crash

Solution
I suspect it was because the code is using a singleton which creates a pointer only once, but when the process ends, it loads a different instance and the pointer do not match to the new instance.

Remove the singleton and use something different.

Sample Data
pgRouting's sampledata