[Bug c/62024] __atomic_always_lock_free is not a constant expression

[amanieu at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62024

--- Comment #2 from Amanieu d'Antras <amanieu at gmail dot com> ---
A similar error happens when trying to use the result of
__atomic_always_lock_free as the size of an array:

int array[__atomic_always_lock_free(sizeof(int), 0)];

test.c:1:5: error: variably modified ‘array’ at file scope