On Sun, 2009-09-27 at 14:24 -0300, Cesar Eduardo Barros wrote:
I took a quick look, and all uses seem to be directly in a boolean context (within an if()), so there would be no problem. Besides, the unlikely() all these macros end with does a double negation, meaning even if it is an int, it will be either 0 or 1 (but I am not sure I am reading these macros right - it seems CONFIG_TRACE_BRANCH_PROFILING turns all unlikely() into likely()).
In fact, I was expecting no change at all, since gcc should be able to see it is being treated as a boolean (perhaps I am trusting gcc too much). And to make matters even more confusing, my own test changing all __ret_warn_once to bool and dropping the !! caused an _increase_ of 598 bytes (x86-64 defconfig).
text data bss dec hex filename
8100553 1207148 991988 10299689 9d2929 vmlinux.warnret.before
8101119 1207180 991988 10300287 9d2b7f vmlinux.warnret.after
(And yes, data increased again.)
Did you have the CONFIG_TRACE_BRANCH_PROFILING option enabled for the
test above?
If this was just your regular base line config , then that is odd .. I
also would think worse case would be no size reduction .. I did my
compile test on x86-32 btw..