On Fri, 15 Dec 2000, Andrea Arcangeli wrote:
> On Fri, Dec 15, 2000 at 11:18:35AM -0800, Ulrich Drepper wrote:
> > Andrea Arcangeli <andrea@suse.de> writes:
> >
> > > x()
> > > {
> > >
> > > switch (1) {
> > > case 0:
> > > case 1:
> > > case 2:
> > > case 3:
> > > ;
> > > }
> > > }
> > >
> > > Why am I required to put a `;' only in the last case and not in all
> > > the previous ones? Or maybe gcc-latest is forgetting to complain about
> > > the previous ones ;)
> >
> > Your C language knowledge seems to have holes. It must be possible to
> > have more than one label for a statement. Look through the kernel
> > sources, there are definitely cases where this is needed.
>
> I don't understand what you're talking about. Who ever talked about
> "more than one label"?
In simple terms all four `case'es form a single entity and therefore a
statement is necessary AFTER them and not in the MIDDLE. That is why gcc
doesn't complain about the `previous' ones.
> The only issue here is having 1 random label at the end of a compound
> statement. Nothing else.
That is NOT the issue. It has nothing to do with the compound statement.
There should be a statement after ONE OR MORE "case"s, but here
case 0: case 1: case 2: case 3:
is NOT followed by a statement.
> And yes I can see that the whole point of the change is that they want
> to also forbids this:
>
> x()
> {
> goto out;
> out:
> }
Again this is a similar case. But if you write
x()
{
goto out1;
goto out2;
out1:
out2:
}
GCC will complain the absence of a statement after `out1:out2:`, but not
two complains for `out1' and `out2', because they form a single entity.
Anuradha
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