[Bug c++/87951] GCC warns about reaching end of non-void function when all switch is completely handled

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87951

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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                 CC|                            |jakub at gcc dot gnu.org

--- Comment #13 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
(In reply to Jonathan Wakely from comment #12)
> It's not a useless warning. If I call your function from comment 7 like
> this, I get undefined behaviour:
> 
>   CoverMyBases( Enum{2} );
> 
> Your switch is undefined for this code. That's what GCC is warning you
> about. To tell GCC you will never call the function with any value except
> Enum::A or Enum::B, add
> 
>   default: __builtin_unreachable();

Maybe better to add it after the switch if you want to make sure that you get a
warning with -Wswitch if a new enumerator is added.