So I am wondering if it is guaranteed that t.a == 0 and t.b == 1? This will always be true so long as a comes before b in the class declaration and nothing else calls f() between the initialization of a and b. Class members are initialized in the order they are declared in … Read more
I’m pretty sure it’s defined, and x should have the value 1. ยง3.6.2/1 says: “Objects with static storage duration (3.7.1) shall be zero-initialized (8.5) before any other initialization takes place.” After that, I think it’s all pretty straightforward.
You have answered your own question. Static initialization order is undefined, and the most elegant way around it (while still doing static initialization i.e. not refactoring it away completely) is to wrap the initialization in a function. Read the C++ FAQ items starting from https://isocpp.org/wiki/faq/ctors#static-init-order