On Wed, 2017-11-15 at 12:25 -0500, David Malcolm wrote:
> 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
Actually, https://gcc.gnu.org/ml/gcc-regression/2017-11/msg00157.html
has a tighter range: r254628 vs r254635.
Looking at:
svn log -r r254628:r254635 |less
I see msebor's r254630 ("PR c/81117 - Improve buffer overflow checking
in strncpy") has:
* gimple.c (gimple_build_call_from_tree): Set call location.
with:
+ gimple_set_location (call, EXPR_LOCATION (t));
Maybe that's it? (nothing else in that commit range seems to affect
locations).
Dave
