Michael Tautschnig <[email protected]> writes: >> In this specific case, it would probably be fine for the MIT Kerberos code >> base to change this line to instead be: >> >> #if !defined(TARGET_OS_MAC) > ^ (Sure? I don't think negation is due here.)
Ack, you're correct. I reversed the sense. > So I do believe that > ^\s*#\s*if\s+[a-zA-Z_][a-zA-Z0-9_]*\s*$ > is almost always wrong as those should really be #ifdef ... or #if > defined(...), but there may be more complex expressions that are wrong > as well. Fixing this appears to be a worthwhile (but indeed possibly > non-trivial) goal. There used to be a coding style that recommended #if over #ifdef for stuff like this, but I forget why. I'm not sure if you can use #ifdef with #elif. I've always avoided doing so, but have to admit having not looked it up in the C standard. I generally agree with you that it would be better to write -Wundef-clean code, but a lot of examples from, say, Autoconf are not -Wundef-clean, so I suspect there's a lot of this out there. And since behavior of an undefined variable in preprocessor directives is well-defined by the standard, you'll probably get pushback against making it a rule. -- Russ Allbery ([email protected]) <http://www.eyrie.org/~eagle/> -- To UNSUBSCRIBE, email to [email protected] with a subject of "unsubscribe". Trouble? Contact [email protected]
