[SYCL] Fix library destructor priority value

[alexbatashev]

No description provided.

[romanovvlad]

What about setting something like 110 to let other libraries to have a destructor which works after SYCL one.
@smaslov-intel @alexbatashev What do you think?

[alexbatashev]

Makes sense, I think

[smaslov-intel]

Should we document it somewhere what priority are for what? And how it interacts with no priority specified?

[alexbatashev]

I conducted a small experiment:

#include <iostream>

__attribute__((destructor(101))) static void syclUnload101() {
    std::cout << "101\n";
}

__attribute__((destructor(102))) static void syclUnload102() {
    std::cout << "102\n";
}

__attribute__((destructor(110))) static void syclUnload110() {
    std::cout << "110\n";
}

__attribute__((destructor(105))) static void syclUnload105() {
    std::cout << "105\n";
}

__attribute__((destructor)) static void syclUnload() {
    std::cout << "default\n";
}

int main() {
    std::cout << "Hi\n";
    return 0;
}

The result is the same for both GCC and Clang:

Hi
default
110
105
102
101