[Development] Compiler warnings

[Milian Wolff]

On Friday 17 October 2014 12:44:09 Bo Thorsen wrote:
> Den 17-10-2014 12:22, Julien Blanc skrev:
> > On 17/10/2014 10:15, Christian Kandeler wrote:
> >> On 10/17/2014 08:48 AM, Kurt Pattyn wrote:
> >>> As we are developing for aerospace, avionics, defence and healthcare, we
> >>> are confronted on a daily basis with a lot of very stringent rules that
> >>> we have to comply with (irrespective if some people might find these
> >>> rules outdated, stupid, ridiculous or not). That's why we always
> >>> compile with as much compiler warnings as possible. Our code must be
> >>> audited by an external office anyways, so we better make sure we can
> >>> avoid a bad report as soon as possible. Some examples of 'stupid' rules
> >>> (which after second consideration aren't that stupid after all): - a
> >>> switch statement must always have a default statement (also all cases
> >>> must be handled)>> 
> >> Doesn't this actually make the code *worse* when using enums? Adding a
> >> default statement when you handle all possible values will inhibit
> >> genuine compiler warnings when you forget to add a case for a newly
> >> added enum value. In fact, this is almost guaranteed to happen in a
> >> non-trivial project, so this rule seems almost absurdly wrong to me.
> > 
> > That one is always subject to debate. There is one thing not to forget
> > in favor of this rule : enums are *not* guaranted to have a value
> > amongst the defined ones. Undefined behaviour in that case is not an
> > option.
> > 
> > I wish i could have both a default statement and my compiler warning…
> 
> switch (enumValue) {
> case E1: ...; break;
> case E2: ...; break;
> 
> case Nope1:
> case Nope2:
>    // Intentionally not handled
>    break;
> }
> 
> Boom. Can I invoice you for this now? :)

I think you are missing something:

enum Foo {
Bar = 1, Baz = 2
};

Foo foo = static_cast<Foo>(3);

Now what do you do without a default clause?

Bye
-- 
Milian Wolff | milian.wolff at kdab.com | Software Engineer
KDAB (Deutschland) GmbH&Co KG, a KDAB Group company
Tel. Germany +49-30-521325470, Sweden (HQ) +46-563-540090
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