https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100047
Aldy Hernandez <aldyh at gcc dot gnu.org> changed:
What |Removed |Added
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CC| |aldyh at gcc dot gnu.org,
| |law at gcc dot gnu.org
--- Comment #3 from Aldy Hernandez <aldyh at gcc dot gnu.org> ---
(In reply to Martin Sebor from comment #2)
> Confirmed with GCC 11 and 10 and -Og only with the GCC 11 IL below. The
> warning depends on a number of optimizations only a few of which are enabled
> at -Og so it has a higher rate of false positives there. For GCC 12 with
> -Og we might consider removing -Wmaybe-uninitialized from -Wall.
The threaders reduce the false positive rate for -Wuninitialized and friends,
however hardly any of them run at -O1 and -Og:
$ ./cc1 a.c -fdump-tree-all-details -quiet -I/tmp -Og -Wall
$ ls a.c.*thread*
a.c.034t.ethread
I think the only semi-useful threader at -O1 is DOM which uses evrp under the
covers.
An uneducated suggestion would be to remove these warnings from Wall at < O2.
Though I think if we convert the threading done at DOM to use the backward
threader (when ranger can do floats), we should be able to get this at -O1,
assuming we agree on the time penalty.
