This is the mail archive of the
gcc-bugs@gcc.gnu.org
mailing list for the GCC project.
[Bug fortran/68649] [6 Regression] note: code may be misoptimized unless -fno-strict-aliasing is used
- From: "dominiq at lps dot ens.fr" <gcc-bugzilla at gcc dot gnu dot org>
- To: gcc-bugs at gcc dot gnu dot org
- Date: Wed, 02 Dec 2015 11:42:22 +0000
- Subject: [Bug fortran/68649] [6 Regression] note: code may be misoptimized unless -fno-strict-aliasing is used
- Auto-submitted: auto-generated
- References: <bug-68649-4 at http dot gcc dot gnu dot org/bugzilla/>
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68649
Dominique d'Humieres <dominiq at lps dot ens.fr> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Ever confirmed|0 |1
--- Comment #6 from Dominique d'Humieres <dominiq at lps dot ens.fr> ---
> seems certainly related, but PR68560 doesn't yield the worrying
> 'code may be misoptimized unless -fno-strict-aliasing is used'.
> I'll just add a dependency.
IMO these warnings are false positive (aka bogus). The minimal set of options
to get the warning for the test in comment 1 is '-flto -fstrict-aliasing'.
> I'm thinking the issue is on the Fortran FE side, LTO shouldn't know
> the language involved. I guess some middle end person might need to have
> a look however.
IMO the first step is to understand why LTO is emitting these warning on valid
Fortran code. Then, if this not due to a bug in LTO, it will be time to find
how Fortran intrinsics have to be "decorated" to avoid the warnings.