Since #15233 has been merged, the `lockdata` becomes a static local variable with a well-defined initialization order: https://github.com/bitcoin/bitcoin/blob/36c0abd8f61ba859d53b1e59014720282c97c143/src/sync.cpp#L93-L96

Its destructor `~LockData()` [is called at program exit](https://en.cppreference.com/w/cpp/utility/program/exit).

At the same time, "if a function-local ... static object was destroyed and then that function is called from the destructor..., the _behavior is undefined_."

It seems possible that at program exit the `lockdata` object is destroyed before a global `RecursiveMutex` destructor calls `DeleteLock()`, which in turn calls `GetLockData()` with UB.
{
    pop_lock();
}
std::string LocksHeld()
{
    std::string result;
    for (const std::pair<void*, CLockLocation>& i : g_lockstack)
        result += i.second.ToString() + std::string("\n");
    return result;
}
void AssertLockHeldInternal(const char* pszName, const char* pszFile, int nLine, void* cs)
{
    for (const std::pair<void*, CLockLocation>& i : g_lockstack)
        if (i.first == cs)
            return;
    tfm::format(std::cerr, "Assertion failed: lock %s not held in %s:%i; locks held:\n%s", pszName, pszFile, nLine, LocksHeld());
    abort();
}
void AssertLockNotHeldInternal(const char* pszName, const char* pszFile, int nLine, void* cs)
{
    for (const std::pair<void*, CLockLocation>& i : g_lockstack) {
        if (i.first == cs) {
            tfm::format(std::cerr, "Assertion failed: lock %s held in %s:%i; locks held:\n%s", pszName, pszFile, nLine, LocksHeld());
            abort();
        }
    }
}
void DeleteLock(void* cs)