On Wed, 2017-11-15 at 12:06 -0500, David Malcolm wrote:
> On Wed, 2017-11-15 at 08:03 -0500, Nathan Sidwell wrote:
> > g++.dg/lambda/lambda-switch.C Has recently regressed.
>
> g++.dg/cpp0x/lambda/lambda-switch.C
>
> > It appears the
> > location of a warning message has moved.
> >
> > l = []() // { dg-warning "statement will never
> > be executed" }
> > {
> > case 3: // { dg-error "case" }
> > break; // { dg-error "break" }
> > }; <--- warning now here
> >
> > We seem to be diagnosing the last line of the statement, not the
> > first.
> > That seems not a useful.
> >
> > I've not investigated what patch may have caused this, on the
> > chance
> > someone might already know?
> >
> > nathan
>
> The warning was added in r236597 (aka
> 1398da0f786e120bb0b407e84f412aa9fc6d80ee):
>
> +2016-05-23 Marek Polacek <pola...@redhat.com>
> +
> + PR c/49859
> + * common.opt (Wswitch-unreachable): New option.
> + * doc/invoke.texi: Document -Wswitch-unreachable.
> + * gimplify.c (gimplify_switch_expr): Implement the -Wswitch-
> unreachable
> + warning.
>
> which had it at there (23:7).
>
> r244705 (aka 3ef7eab185e1463c7dbfa2a8d1af5d0120cf9f76) moved the
> warning from 23:7 up to the "[] ()" at 19:6 in:
>
> +2017-01-20 Marek Polacek <pola...@redhat.com>
> +
> + PR c/64279
> [...snip...]
> + * g++.dg/cpp0x/lambda/lambda-switch.C: Move dg-warning.
>
> I tried it with some working copies I have to hand:
> - works for me with r254387 (2017-11-03)
> - fails for me with r254700 (2017-11-13)
>
> so hopefully that helps track it down.
>
> Dave
Searching in the November archives of the gcc-regression ML for
"lambda-switch.c":
https://gcc.gnu.org/cgi-bin/search.cgi?wm=wrd&form=extended&m=all&s=D&q=lambda-switch.c&ul=%2Fml%2Fgcc-regression%2F2017-11%2F%25
showed e.g.:
https://gcc.gnu.org/ml/gcc-regression/2017-11/msg00173.html
"Regressions on trunk at revision 254648 vs revision 254623"
which says this is a new failure somewhere in that range; so it
presumably happened sometime on 2017-11-10 after r254623 and up to
(maybe ==) r254648.
Looking at:
svn log -r r254623:r254648 |less
nothing jumps out at me as being related.
Hope this is helpful
Dave
