On Fri, May 26, 2017 at 02:13:56PM -0600, Martin Sebor wrote:
> On 05/26/2017 01:59 PM, David Malcolm wrote:
> > Ping:
> > https://gcc.gnu.org/ml/gcc-patches/2017-05/msg00334.html
> >
> > On Thu, 2017-05-04 at 14:16 -0400, David Malcolm wrote:
> > > As of r247522, fix-it-hints can suggest the insertion of new lines.
> > >
> > > This patch updates -Wimplicit-fallthrough to provide suggestions
> > > with fix-it hints, showing the user where to insert "break;" or
> > > fallthrough attributes.
> > >
> > > For example:
> > >
> > > test.c: In function 'set_x':
> > > test.c:15:9: warning: this statement may fall through [-Wimplicit
> > > -fallthrough=]
> > > x = a;
> > > ~~^~~
> > > test.c:22:5: note: here
> > > case 'b':
> > > ^~~~
> > > test.c:22:5: note: insert '__attribute__ ((fallthrough));' to
> > > silence this warning
> > > + __attribute__ ((fallthrough));
> > > case 'b':
> > > ^~~~
> > > test.c:22:5: note: insert 'break;' to avoid fall-through
> > > + break;
> > > case 'b':
> > > ^~~~
>
> I haven't read the patch but the notes above make me wonder:
>
> If the location of at least one of t hints is always the same
> as that of the first "note: here" would it make sense to lose
> the latter and reduce the size of the output? (Or lose it in
> the cases where one of the fix-it hints does share a location
> with it).
I agree that it's a tad verbose but I'm not sure if it'd be easy
to suppress printing
case 2:
^~~~
more times simple enough. So I'd be fine with the current state.
I'd also be happy with e.g.
a.c: In function ‘foo’:
a.c:7:9: warning: this statement may fall through [-Wimplicit-fallthrough=]
x = 1;
~~^~~
a.c:8:5: note: here
case 2:
^~~~
a.c:8:5: note: insert ‘__attribute__ ((fallthrough));’ to silence this warning
+ __attribute__ ((fallthrough));
or insert ‘break;’ to avoid fall-through
+ break;
but I don't think we've got the means to do so.
On the patch, I'd think that add_newline_fixit_with_indentation doesn't
belong to gimplify.c, even though it only has one user. But I won't be
able to approve it in any case.
Marek
