In the following example, it seems
that 'bar' could be optimized to
return '1' and every else could be
optimized away. Or am I missing
something? Do I need to add
some specific compiler flags?
static int a = 1;
static int *p;
extern
void foo(void)
{
p = &a;
}
extern
int bar(void)
{
retu
Am Dienstag, den 11.02.2020, 21:43 +0100 schrieb Richard Biener:
> On February 11, 2020 9:32:14 PM GMT+01:00, "Uecker, Martin"
>
> wrote:
> >
> > In the following example, it seems
> > that 'bar' could be optimized to
> > return '1&#x
Hi all,
the following code compiles into a mov instruction
on x86_64. I wonder why. The struct has alignment 4,
so a mov might not be atomic if the struct is not
alligned to its full size. For this reason,
I expected a call to libatomic instead
(LLVM does this). What am I missing?
The docume
I tested a recent GCC from git and noticed a couple
of new warnings for VLA parameters.
(Martin, I assume this is your work. First, let me
say: thank you! I think this is really important.)
Here is some feedback from running this on an
existing code base. See below for comments and
toy example
> On Wed, Nov 04, 2020 at 07:31:42PM +0100, Uros Bizjak wrote:
> > Hello!
> >
> > I was looking at the recent linux patch series [1] where segment
> > qualifiers (named address spaces) were introduced to handle percpu
> > variables. In the patch [2], the author mentions that:
> >
> > --q--
> > U
Am Montag, den 16.11.2020, 12:10 +0100 schrieb Peter Zijlstra:
> ( restoring at least linux-toolcha...@vger.kernel.org, since that
> seems
> to have gone missing )
>
> On Mon, Nov 16, 2020 at 10:11:50AM +0100, Richard Biener wrote:
> > On Sun, Nov 15, 2020 at 11
Am Dienstag, den 17.11.2020, 11:31 -0800 schrieb Linus Torvalds:
> On Tue, Nov 17, 2020 at 11:25 AM Jakub Jelinek wrote:
> >
> > It would need to be typeof( (typeof(type)) (type) ) to not be that
> > constrained on what kind of expressions it accepts as arguments.
>
> Yup.
>
> > Anyway, it won'
Hi Richard,
Am Mittwoch, den 17.04.2019, 11:41 +0200 schrieb Richard Biener:
> On Wed, Apr 17, 2019 at 11:15 AM Peter Sewell
> wrote:
> >
> > On 17/04/2019, Richard Biener wrote:
> > > On Fri, Apr 12, 2019 at 5:31 PM Peter Sewell
> > > wrote:
...
> > > So this is not what GCC implements whi
Am Mittwoch, den 17.04.2019, 14:41 +0200 schrieb Richard Biener:
> On Wed, Apr 17, 2019 at 1:53 PM Uecker, Martin
> wrote:
> >
> > > Since
> > > your proposal is based on an abstract machine there isn't anything
> > > like a pointer with mult
Am Mittwoch, den 17.04.2019, 15:34 +0200 schrieb Richard Biener:
> On Wed, Apr 17, 2019 at 2:56 PM Uecker, Martin
> wrote:
> >
> > Am Mittwoch, den 17.04.2019, 14:41 +0200 schrieb Richard Biener:
> > > On Wed, Apr 17, 2019 at 1:53 PM Uecker, Martin
> > &g
Am Donnerstag, den 18.04.2019, 11:56 +0200 schrieb Richard Biener:
> On Thu, Apr 18, 2019 at 11:31 AM Richard Biener
> wrote:
> >
> > On Wed, Apr 17, 2019 at 4:12 PM Uecker, Martin
> > wrote:
> > >
> > > Am Mittwoch, den 17.04.2019, 15:34 +0200 schr
Am Donnerstag, den 18.04.2019, 11:45 +0100 schrieb Peter Sewell:
> On Thu, 18 Apr 2019 at 10:32, Richard Biener
> wrote:
> An equality test of two pointers, on the other hand, doesn't necessarily
> mean that they are interchangeable. I don't see any good way to
> avoid that in a provenance sem
Am Donnerstag, den 18.04.2019, 14:30 +0200 schrieb Richard Biener:
> On Thu, Apr 18, 2019 at 1:57 PM Uecker, Martin
> wrote:
> >
> > Am Donnerstag, den 18.04.2019, 11:56 +0200 schrieb Richard Biener:
> > > On Thu, Apr 18, 2019 at 11:31 AM Richard Biener
> >
Am Donnerstag, den 18.04.2019, 14:42 +0200 schrieb Richard Biener:
> On Thu, Apr 18, 2019 at 2:20 PM Uecker, Martin
> wrote:
> >
> > Am Donnerstag, den 18.04.2019, 11:45 +0100 schrieb Peter Sewell:
> > > On Thu, 18 Apr 2019 at 10:32, Richard Biener
> > > wro
Am Donnerstag, den 18.04.2019, 07:42 -0600 schrieb Jeff Law:
> On 4/18/19 6:20 AM, Uecker, Martin wrote:
> > Am Donnerstag, den 18.04.2019, 11:45 +0100 schrieb Peter Sewell:
> > > On Thu, 18 Apr 2019 at 10:32, Richard Biener
> > > wrote:
...
> > 4.) Compile
Am Donnerstag, den 18.04.2019, 15:49 +0100 schrieb Peter Sewell:
> On Thu, 18 Apr 2019 at 14:54, Uecker, Martin
> wrote:
> >
> > Am Donnerstag, den 18.04.2019, 07:42 -0600 schrieb Jeff Law:
> > > On 4/18/19 6:20 AM, Uecker, Martin wrote:
> > > > Am Donnerst
Am Freitag, den 19.04.2019, 10:19 +0200 schrieb Jens Gustedt:
> Hello,
>
> On Thu, 18 Apr 2019 14:42:22 +0200 Richard Biener
> wrote:
>
> > On Thu, Apr 18, 2019 at 2:20 PM Uecker, Martin
> > wrote:
> > > 1.) Compilers do not use conditional equivalences for
Am Freitag, den 19.04.2019, 10:35 +0100 schrieb Peter Sewell:
> On 19/04/2019, Jens Gustedt wrote:
> > Hello Peter,
> >
> > On Fri, 19 Apr 2019 10:11:43 +0100 Peter Sewell
> > wrote:
> >
> > > On 19/04/2019, Jakub Jelinek wrote:
> > > > On Fri, Apr 19, 2019 at 10:19:28AM +0200, Jens Gustedt wr
Am Mittwoch, den 24.04.2019, 21:30 +0200 schrieb Philipp Klaus Krause:
> Am 24.04.19 um 20:41 schrieb Jeff Law:
> > > > > 4.) Compilers make sure that exposed objects never
> > > > > are allocated next to each other (as Jens proposed).
> > > >
> > > > Ugh. Not sure how you enforce that. Consider
Hi,
I have a proposal for making changes to the rules for
compatibility of tagged types in C2X (N2366). This was
received with interest by WG14, so there is a chance
that this could get accepted into C2X.
In particular, the idea is to make structs (+ unions, enums)
with the same tag and the sa
Am Mittwoch, den 02.10.2019, 12:47 +0200 schrieb Richard Biener:
> On Wed, Oct 2, 2019 at 12:46 PM Richard Biener
> wrote:
> >
> > On Tue, Oct 1, 2019 at 7:49 PM Uecker, Martin
> > wrote:
...
> > >
> > > In particular, the idea is to make structs (+
Am Mittwoch, den 02.10.2019, 14:18 +0200 schrieb Richard Biener:
> On Wed, Oct 2, 2019 at 1:57 PM Uecker, Martin
> wrote:
> >
Thank you for your answers.
> > Finally, how does LTO does it? It somehow also needs to unify
> > different tagged types? Could we reus
Am Mittwoch, den 02.10.2019, 15:12 +0200 schrieb Richard Biener:
> On Wed, Oct 2, 2019 at 3:10 PM Richard Biener
> wrote:
> >
> > On Wed, Oct 2, 2019 at 2:35 PM Uecker, Martin
> > wrote:
> > >
> > > Am Mittwoch, den 02.10.2019, 14:18 +0200 schrieb Rich
Am Mittwoch, den 02.10.2019, 17:37 +0200 schrieb Richard Biener:
> On October 2, 2019 3:55:43 PM GMT+02:00, "Uecker, Martin"
>
> wrote:
> > Am Mittwoch, den 02.10.2019, 15:12 +0200 schrieb Richard Biener:
> > > On Wed, Oct 2, 2019 at 3:10 PM Richard Biener
&g
Am Freitag, den 04.10.2019, 12:29 +0200 schrieb Richard Biener:
> On Wed, Oct 2, 2019 at 8:24 PM Uecker, Martin
> wrote:
> >
> > Am Mittwoch, den 02.10.2019, 17:37 +0200 schrieb Richard Biener:
> >
> > ...
> >
> > > > > Oh, and LT
Am Freitag, den 04.10.2019, 14:28 +0200 schrieb Richard Biener:
> On Fri, Oct 4, 2019 at 1:55 PM Uecker, Martin
> wrote:
> >
> > Am Freitag, den 04.10.2019, 12:29 +0200 schrieb Richard Biener:
> > > On Wed, Oct 2, 2019 at 8:24 PM Uecker, Martin
> > > wrot
Hi,
I want to add run-time support for checking for equality of
the size expressions where pointers to variable-length arrays
are required to be compatible.
I wonder if you could give some advise on how to approach
this. One general question is where this should be added.
For example, I think it
Hi Richard,
I noticed that GCC 11 has different behavior in the following
example relative to 10.2 with -O2. I wonder whether this
is an intentional change and if yes, what are the rules?
Thanks!
Martin
https://godbolt.org/z/57res7ax1
#include
#include
__attribute__((__noinline__, __weak_
Am Montag, den 17.05.2021, 09:08 +0200 schrieb Richard Biener:
> On Sun, May 16, 2021 at 8:57 AM Uecker, Martin
> wrote:
> >
> >
> > Hi Richard,
> >
> > I noticed that GCC 11 has different behavior in the following
> > example relative to 10.2
Am Montag, den 17.05.2021, 09:44 +0200 schrieb Richard Biener:
> On Mon, May 17, 2021 at 9:32 AM Uecker, Martin
> wrote:
> >
> >
> > Am Montag, den 17.05.2021, 09:08 +0200 schrieb Richard Biener:
> > > On Sun, May 16, 2021 at 8:57 AM Uecker, Martin
> >
I wonder if we could get a nice short command-line option
for recommended safety/security related flags.
We have -Ox for optimization and -Wall for a useful set
of recommended warnings.
I am thinking about options such as
-ftrapv
-fsanitize=undefined -fsanitize-undefined-trap-on-error
-fstack
Hi Richard,
here is another case where it seems that TBAA goes
wrong. Since this is not in a loop, it seems this
is something else than what we discussed. Is
this a known issue?
Best,
Martin
#include
#include
union u {
long x;
long long y;
};
__attribute__((noinline,noclone))
long tes
Am Dienstag, dem 29.11.2022 um 14:58 + schrieb Michael Matz:
> Hey,
>
> On Tue, 29 Nov 2022, Alex Colomar via Gcc wrote:
>
> > How about the compiler parsing the parameter list twice?
>
> This _is_ unbounded look-ahead. You could avoid this by using "."
> for
> your new syntax. Use someth
Hi,
Am Dienstag, dem 29.11.2022 um 15:44 + schrieb Michael Matz:
> Hey,
>
> On Tue, 29 Nov 2022, Uecker, Martin wrote:
>
> > It does not require any changes on how arrays are represented.
> >
> > As part of VM-types the size becomes part of the type and this
34 matches
Mail list logo
