Re: [PATCH 1/5] btrfs: add verbose version of ASSERT

[David Sterba <dsterba@suse.cz>]

On Wed, Apr 16, 2025 at 03:03:18PM +0000, Johannes Thumshirn wrote:
> On 16.04.25 11:09, David Sterba wrote:
> > +
> > +/* Verbose assert, use to print any relevant values of the condition. */
> > +#define VASSERT(expr, fmt, ...)					\
> > +	(likely(expr) ? (void)0 : btrfs_assertfail_verbose(#expr, __FILE__, __LINE__, \
> > +							   fmt, __VA_ARGS__))
> >   #else
> >   #define ASSERT(expr)	(void)(expr)
> > +#define VASSERT(expr, fmt, ...)		(void)(expr)
> >   #endif
> 
> Ahm stupid question (applies for ASSERT() as well), doesn't that 
> generate code as well when CONFIG_BTRFS_ASSERT=n? So we're doing a lot 
> of potentially unneeded tests?

It should not generate any code. It's parsed, syntax-checked and as the
result is cast to void it's thrown out and optimized out (-O2).