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Re: GIMPLE Question
On Fri, Feb 25, 2011 at 11:33:58AM -0800, Andrew Pinski wrote:
> On Fri, Feb 25, 2011 at 11:21 AM, Kyle Girard <kyle@kdmanalytics.com> wrote:
> >
> >> ? That *is* the content of the bar method. ?What exactly do you expect to see
> >> happening when you assign a class with no members? ?There's nothing to do!
> >
> >
> > I was hoping to see the assignment. ?My example might have been a little
> > too simple. ?Here's a slightly more complex example:
> >
> > foo.hh
> >
> > class A
> > {
> > public:
> > ? void yay(){};
> > };
>
> A is still an empty class, try adding "int a;" and you will see some code there.
The fact that passing an empty class has zero cost is used quite a bit in
the design of the standard library to generate efficient specialized
templates. The empty objects are just used to select the correct
overloaded form.