[RFC] Turn off -Wmaybe-uninitialized completely and move it to W=1

From: Borislav Petkov
Date: Mon Jun 16 2014 - 09:21:02 EST


Hi,

so 3.16-rc1 adds this false positive from gcc, see below (triggers on
4.9 and 4.8.2). Now, it is firing wrong and gcc people tell me there's
no way for the compiler to know that the "from" and "to" values will NOT
be used in the error case, i.e. thus the "maybe" aspect.

So, we've disabled it for -Os already:

e74fc973b6e5 ("Turn off -Wmaybe-uninitialized when building with -Os")

maybe we want to disable it by default on all and move it to W=1. This
way people can still have it fire but not by default. And from what I've
seen so far, it is mostly firing wrong and it is becoming annoying.

So what do people think, any reasons for keeping it enabled by default?

Thanks.

---

fs/direct-io.c: In function â__blockdev_direct_IOâ:
fs/direct-io.c:920:9: warning: âtoâ may be used uninitialized in this function [-Wmaybe-uninitialized]
while (from < to) {
^
fs/direct-io.c:913:16: note: âtoâ was declared here
size_t from, to;
^
fs/direct-io.c:1034:9: warning: âfromâ may be used uninitialized in this function [-Wmaybe-uninitialized]
from += this_chunk_bytes;
^
fs/direct-io.c:913:10: note: âfromâ was declared here
size_t from, to;


--
Regards/Gruss,
Boris.

Sent from a fat crate under my desk. Formatting is fine.
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