Currently if you try to put an export function and a non-extern function in an array, you get an error because the types don't match: extern functionts and non-extern functions have different calling conventions. Same is true for "cold" functions.

However, we can always use the C calling convention - the other conventions are just more optimal if we don't have to. So when the user would get a calling convention type mismatch, instead, cause the calling convention of the affected functions to all switch to the C calling convention, then all the types are satisfied and the user doesn't have to care that a function was declared "cold" or "export".