[Bug c++/60702] thread_local initialization

[tinrow at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60702

Kan Wang <tinrow at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |tinrow at gmail dot com

--- Comment #5 from Kan Wang <tinrow at gmail dot com> ---
+1 for this. If class member has thread-local storage and is first accessed
through member access operator (e.g. a.foo), it is not initialized as expected.

The short code snippet below reproduces the bug on g++ 4.8 - 7.1

#include <iostream>
int init() {
    std::cout << "init" << std::endl;
    return 0;
}

struct A {
    static thread_local int foo;
};
thread_local int A::foo { init() };

int main() {
    A a;
    int i = a.foo;
    std::cout << "--- should be initialized above ---" << std::endl;
    i = A::foo;
    return i;
}

Output:
--- should be initialized above ---
init