On 4/18/20 11:53 AM, Linus Torvalds wrote:
On Sat, Apr 18, 2020 at 11:41 AM Randy Dunlap rdunlap@infradead.org wrote:
Fix gcc empty-body warning when -Wextra is used:
Please don't do this.
First off, "do_empty()" adds nothing but confusion. Now it syntactically looks like it does something, and it's a new pattern to everybody. I've never seen it before.
Secondly, even if we were to do this, then the patch would be wrong:
if (cmpxchg(p, ACL_NOT_CACHED, sentinel) != ACL_NOT_CACHED)
/* fall through */ ;
do_empty(); /* fall through */That comment made little sense before, but it makes _no_ sense now.
What fall-through? I'm guessing it meant to say "nothing", and somebody was confused. With "do_empty()", it's even more confusing.
Thirdly, there's a *reason* why "-Wextra" isn't used.
The warnings enabled by -Wextra are usually complete garbage, and trying to fix them often makes the code worse. Exactly like here.
OK, no problem. That's why PATCH 0/9 says RFC.
Oops. Crap. It was *supposed* to say RFC. :(