On 23.07.2013, at 23:52, Peter Maydell wrote: > On 23 July 2013 22:36, Alexander Graf <ag...@suse.de> wrote: >> >> >> Am 23.07.2013 um 23:16 schrieb Peter Maydell <peter.mayd...@linaro.org>: >> >>> On 23 July 2013 20:15, Peter Maydell <peter.mayd...@linaro.org> wrote: >>>> I had a thought about this. Suppose we have our class header >>>> files do something like this: >>>> >>>> #ifdef MYCLASS_IMPLEMENTATION >>>> #define PRIVATE >>>> #else >>>> #ifdef __GNUC__ >>>> #define PRIVATE __attribute__((deprecated("this is a private field"))) >>>> #else >>>> #define PRIVATE >>>> #endif >>>> >>>> typedef struct MyObject { >>>> int publicfield; >>>> int privatefield PRIVATE; >>>> } MyObject; >>> >>> Forgot to say, but if people don't think this is an >>> intrinsically terrible idea I'll put together a patch that >>> does this sometime this week. >> >> I like the idea, but could we make this slightly less upper case? Something >> like >> >> __private int privatefield; >> >> feels more readable imho. > > Well, __ is using the reserved namespace, but we could use something > else, and it looks like gcc lets us put the attribute at the front. > Since we'll want to undef whatever we pick after the struct is defined > we can actually use pretty much anything without worrying about it > stealing namespace.
Very nice :). And it aligns pretty well with the __user hint in Linux. > (We could even use just 'private' if we didn't mind (a) not being > able to compile with a C++ compiler and (b) confusing everybody > completely :-)) > >> Or maybe >> >> struct MyObject { >> PUBLIC_FIELDS >> __field int publicfield; >> PRIVATE_FIELDS >> __field int privatefield; >> } > > I can't see an obvious way to make those do the right > thing with the C preprocessor... am I missing something? No, I'm probably just daydreaming :). Macros can't redefine other defines, so this probably won't work.... So yes, prepending the visibility on every field seems to be the most straight forward choice. Alex