This is the mail archive of the gcc-patches@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: Implement -Wswitch-fallthrough


On 07/12/2016 04:30 AM, Marek Polacek wrote:
On Tue, Jul 12, 2016 at 12:27:31PM +0200, Richard Biener wrote:
On Mon, Jul 11, 2016 at 9:43 PM, Marek Polacek <polacek@redhat.com> wrote:
The switch fallthrough has been widely considered a design defect in C, a
misfeature or, to use Marshall Cline's definition, evil.  The overwhelming
majority of the time you don't want to fall through to the next case, but it is
easy to forget to "break" at the end of the case, making this far too error
prone.  Yet GCC (and probably other compilers, too) doesn't have the ability to
warn in this case.  A feature request for such warning was opened back in 2002,
but it's mostly been untouched since.  But then the [[fallthrough]] attribute was
approved for C++17 [1], and that's what has got me to do all this.

I don't like this too much given the churn it requires in GCC itself.
If [[fallthrough]]
was approved for C++17 is there sth similar proposed for C?  Like a keyword
__Fallthrough?

I don't think there is.
But maybe there should be ;-) We've got a couple folks (Martin S and Carlos) that participate in that standards body and could propose it.

jeff


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]