How can I print the result of sizeof() at compile time in C?

Question

How can I print the result of sizeof() at compile time in C?

For now I am using a static assert (home brewed based on other web resources) to compare the sizeof() re

Answer 1

One more way (that actually works):

char __foo[sizeof(MyStruct) + 1] = {[sizeof(MyStruct)] = ""};

Works with old'ish gcc 5.x. Yields an error like this:

a.c:8:54: error: initializer element is not computable at load time
a.c:8:54: note: (near initialization for 'a[8]')

p.s. obviously, this one is (very) gcc specific. All other methods weren't working for me.