> On Tue, 10 Dec 2024, Jan Hubicka wrote:
>
> > Hi,
> > int:
> > struct foo
> > {
> > int a;
> > void bar() const;
> > ~foo()
> > {
> > if (a != 42)
> > __builtin_abort ();
> > }
> > };
> > __attribute__ ((noinline))
> > void test(const struct foo a)
> > {
> > int b = a.a;
> > a.bar();
> > if (a.a != b)
> > __builtin_printf ("optimize me away");
> > }
> > struct foo is passed by invisible reference. As discussed in the PR,
> > since it is declared const, it can not change before function test
> > returns. This makes it possible to optimize out the conditional.
>
> Doesn't this break the case where 'a' is declared mutable?
Hmm, good point. declaring a mutable definitely lets me to chagne value
in bar. I am adding Jason and Jonatan to CC.
We could probably special case types containing mutable if such code is
valid?
Honza
