[Bug c++/30357] Enum typecast warning

[redi at gcc dot gnu dot org]

------- Comment #3 from redi at gcc dot gnu dot org  2009-12-08 21:30 -------
(In reply to comment #2)
> I am not sure this is such a good idea. A casting typically means "I want to
> really do this". GCC normally suppress warnings when casting is added. A
> warning when you assign when enum type to another and the first enum is not a
> subset of the second could still be useful, but the casting should prevent the
> warning.

That won't even compile without a cast, in C++ there is no implicit conversion
to enumeration types.

> I am not sure what happens for such assignment, is it undefined behaviour?

If the source value is within the range of the target enum it's well-defined. 
It might be reasonable to warn as part of -Wconversion except that usually
applies to implicit conversions, and for enums the implicit conversion isn't
allowed.


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30357