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bug#43725: 28.0.50; Include feature/native-comp into master
From: |
Pip Cet |
Subject: |
bug#43725: 28.0.50; Include feature/native-comp into master |
Date: |
Fri, 19 Feb 2021 15:00:16 +0000 |
On Fri, Feb 19, 2021 at 2:35 PM Andrea Corallo <akrl@sdf.org> wrote:
> > On Fri, Feb 19, 2021 at 2:16 PM Andrea Corallo <akrl@sdf.org> wrote:
> >> >> > comp.c:1174:22: warning: logical ‘or’ of collectively exhaustive
> >> >> > tests is always true [-Wlogical-op]
> >> >> > 1174 | if (val > LONG_MAX || val < LONG_MIN)
> >> >> > | ^~
> >> >> >
> >> >> > Not sure what's the best way to silence it or if we want to revert to
> >> >> > the previous formulation.
> >> >>
> >> >> Maybe it's me, but I had a hard time parsing that warning. IIUC, the
> >> >> tests are both trivially false? And oring two trivially false
> >> >> conditions shouldn't trigger a warning, should it?
> >> >
> >> > No, I think it tries to say that val is always either greater than
> >> > LONG_MAX or smaller than LONG_MIN.
> >>
> >> Exactly, the warning is about the fact that all the other conditions
> >> will never be evaluated. The phrasing is admittedly quite cryptic tho.
> >
> > I thought you said this was a setup where the argument _does_ fit a long?
>
> There we are dispatching if 'val' can be expressed or not with a long.
>
> 'val' is an EMACS_INT so depending on the configuration it might fit in
> a long by definition, when this happen GCC sees the first condition in
> or as always true etc etc... :)
So val is greater than LONG_MAX? How can this happen?
I've got some initial results here that seem to show a serious bug in
my backend in this situation, and I hope it's not a gcc bug...
- bug#43725: 28.0.50; Include feature/native-comp into master, (continued)
- bug#43725: 28.0.50; Include feature/native-comp into master, Pip Cet, 2021/02/19
- bug#43725: 28.0.50; Include feature/native-comp into master, Eli Zaretskii, 2021/02/19
- bug#43725: 28.0.50; Include feature/native-comp into master, Andrea Corallo, 2021/02/19
- bug#43725: 28.0.50; Include feature/native-comp into master, Pip Cet, 2021/02/19
- bug#43725: 28.0.50; Include feature/native-comp into master, Andrea Corallo, 2021/02/19
- bug#43725: 28.0.50; Include feature/native-comp into master, Eli Zaretskii, 2021/02/19
- bug#43725: 28.0.50; Include feature/native-comp into master,
Pip Cet <=
- bug#43725: 28.0.50; Include feature/native-comp into master, Andrea Corallo, 2021/02/19
- bug#43725: 28.0.50; Include feature/native-comp into master, Andy Moreton, 2021/02/19
bug#43725: 28.0.50; Include feature/native-comp into master, Andrea Corallo, 2021/02/18
bug#43725: 28.0.50; Include feature/native-comp into master, Andrea Corallo, 2021/02/18