Refactoring conditional directives that break parts of statements.

[lzmths]

A suggestion to compile entire statements and expressions, as suggested by code style guidelines from the Linux Kernel and practitioners.

https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/Documentation/CodingStyle#n892
https://www.cqse.eu/en/blog/living-in-the-ifdef-hell/

It might improve code understanding, maintainability and error-proneness.