Re: NULL

[Luca Barbato <lu_zero@gentoo.org>]

On 09/01/13 15:47, Rich Felker wrote:
> On Wed, Jan 09, 2013 at 03:42:07PM +0100, Luca Barbato wrote:
>> On 09/01/13 12:02, John Spencer wrote:
>>> 2) change musl so it is compatible with those apps. this would mean:
>>> #if defined(__GNUC__) && defined(__cplusplus__)
>>> #define NULL __null
>>> #elif defined (__cplusplus__)
>>> #define NULL 0
>>> #else
>>> #define NULL (void *) 0 /* for C code */
>>> #end
>>> this change is the easiest solution: any problem will be magically fixed.
>>
>> I'm not sure if there is a way to warn properly at compile time for that
>> specific usage.
> 
> __attribute__ ((sentinel)) may be used. Adding this to the appropriate
> gtk headers (even just as a temporary debugging measure if it's not
> desirable permanently) would catch all the bugs calling gtk variadic
> functions.

That would be worthy notwithstanding.

>> IMHO going with 2+3 is the only safe way to grant musl more support
> 
> 2 is not appropriate as written (it's more complexity, and ugly, and
> in multiple locations). 3 already exists; it's called GCC.

=/

>> I wonder why in the hell C++ can't use the (void *) 0 definition or
>> equivalent.
> 
> Because then char *s = NULL; would be a constraint violation.

Indeed, how foolish of me.

lu