[PATCH] linux/fs.h - Convert debug functions declared inline __attribute__((format (printf,x,y) to statement expression macros

David Rientjes rientjes@google.com
Wed Feb 27 05:45:00 GMT 2008


On Tue, 26 Feb 2008, Matthew Wilcox wrote:

> On Tue, Feb 26, 2008 at 08:02:27PM -0800, Joe Perches wrote:
> > Converting inline __attribute__((format (printf,x,y) functions
> > to macros or statement expressions produces smaller objects
> > 
> > before:
> > $ size vmlinux
> >    text    data     bss     dec     hex filename
> > 4716770  474560  618496 5809826  58a6a2 vmlinux
> > after:
> > $ size vmlinux
> >    text    data     bss     dec     hex filename
> > 4716706  474560  618496 5809762  58a662 vmlinux
> 
> > -static inline void __attribute__((format(printf, 1, 2)))
> > -__simple_attr_check_format(const char *fmt, ...)
> > -{
> > -	/* don't do anything, just let the compiler check the arguments; */
> > -}
> > +/* don't do anything, just let the compiler check the arguments; */
> > +
> > +#define __simple_attr_check_format(fmt, args...) \
> > +	do { if (0) printk(fmt, ##args); } while (0)
> 
> That's very interesting.  It's only 64 bytes, but still, it's not
> supposed to have any different effect.  Could you distill a test case
> for the GCC folks and file it in their bugzilla?
> 

I'm not seeing any change in text size with allyesconfig after applying 
this patch with latest git:

   text	   data	    bss	    dec	    hex	filename
32696210	5021759	6735572	44453541	2a64ea5	vmlinux.before
32696210	5021759	6735572	44453541	2a64ea5	vmlinux.after

Joe, what version of gcc are you using?

		David



More information about the Gcc mailing list