Avoid mangling name for tpl class member. Fix #68

[upsuper]

Not sure whether it is the right thing to do.

[highfive]

Warning

• These commits modify unsafe code. Please review it carefully!

[emilio]

Hmm... So I though this avoided getting the mangling for unspecialized methods, but this also avoids that in specialized methods.

I'm fine with not getting symbols for non-specialized templates, because it makes no particular sense (and I guess are the ones that crash), but I guess we can still parse the ones for specialized templates? (Though I think we don't use them yet?).

TLDR: Does a check like self.is_template() && self.specialized() != self instead of just self.is_template() still make the crash go away?

[emilio]

Otherwise I'm fine with merging this, I guess.

[emilio]

Oh, and thanks for digging into this btw :-)

[upsuper]

The minimal reproduce code is:

template<class M> struct A;
template<class C> struct A<void(C::*)()> { static int v; };

and it crashes at the static variable v. Given A<void(C::*)()> looks like a specialized template (correct me if I'm wrong. I'm not very familiar with these concepts), I suppose checking is_specialized wouldn't fix the crash?

[emilio]

Well, it's not specialized completely, since you still don't know the C type.

Does something like:

template<class M> struct A;
template<>
struct A<int> {
    static int foo;
};

still crash?

[emilio]

Also, even if it still crashes, can you add a comment on the cursor_mangling function saying why we're returning early? I don't want anybody to remove it accidentally :)

[upsuper]

That doesn't crash. But how can we check whether one template is fully specialized? It seems to me specialized() is for finding the less specialized one the template is from.

[emilio]

Hm... that's right. I think you can do:

fn is_complete_template_specialization(&self) -> bool {
    self.is_template() && self.num_template_args() > 0
}

Since the last method only works for complete specializations.

[emilio]

You can drop the parent.is_template() check here, since is already part of is_fully_specialized_template().

[upsuper]

You can't, because is_fully_specialized_template() is negated, so if you remove parent.is_template(), it would return true for non-templates.

[emilio]

r=me with that

@bors-servo: delegate+

[bors-servo]

✌️ @upsuper can now approve this pull request

[emilio]

You're right,

@bors-servo: r+

[bors-servo]

📌 Commit dd5962b has been approved by emilio

[bors-servo]

⚡ Test exempted - status