This is the mail archive of the
elfutils-devel@sourceware.org
mailing list for the elfutils project.
Re: [PATCH] elfcmp: fix self-comparison error with GCC 6
- From: Mark Wielaard <mjw at redhat dot com>
- To: elfutils-devel at lists dot fedorahosted dot org
- Date: Mon, 11 Apr 2016 17:13:58 +0200
- Subject: Re: [PATCH] elfcmp: fix self-comparison error with GCC 6
On Mon, 2016-04-11 at 16:00 +0200, david.abdurachmanov(a)cern.ch wrote:
> From: David Abdurachmanov <davidlt@cern.ch>
>
> Noticed with Fedora 24 Alpha, gcc (GCC) 6.0.0 20160406
> (Red Hat 6.0.0-0.20).
>
> elfcmp.c: In function ‘main’:
> elfcmp.c:364:199: error: self-comparison always evaluates
> to false [-Werror=tautological-compare]
> if (unlikely (name1 == NULL || name2 == NULL
> @@ -368,7 +368,7 @@ main (int argc, char *argv[])
> && sym1->st_shndx != SHN_UNDEF)
> || sym1->st_info != sym2->st_info
> || sym1->st_other != sym2->st_other
> - || sym1->st_shndx != sym1->st_shndx))
> + || sym1->st_shndx != sym2->st_shndx))
> {
> // XXX Do we want to allow reordered symbol tables?
> symtab_mismatch:
Thanks! And oops. Applied since that was obviously wrong.
Nice that GCC caught that. I am slightly surprised my own GCC6 testing
didn't find this. I am using upstream gcc (GCC) 6.0.0 20160410
(experimental). Did you have to do anything special on your Fedora setup
to make GCC detect this?
Thanks,
Mark