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From: Richard Biener <richard.guenther@gmail.com>
Date: Fri, 4 Sep 2020 09:13:41 +0200
Message-ID: <CAFiYyc0=eW5c8TLFDvzhj50K5KdCoZa98_PPJsQji_szthwiJg@mail.gmail.com>
Subject: Re: A silly question regarding function types
To: Gary Oblock <gary@amperecomputing.com>
Cc: "gcc@gcc.gnu.org" <gcc@gcc.gnu.org>
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On Fri, Sep 4, 2020 at 4:39 AM Gary Oblock via Gcc <gcc@gcc.gnu.org> wrote:
>
> Note, isn't a problem, rather, it's something that puzzles me.
>
> On walking a function types argument types this way
>
> for ( arg =3D TYPE_ARG_TYPES ( func_type);
>        arg !=3D NULL;
>        arg =3D TREE_CHAIN ( arg))
>     {
>        .
>        .
>      }
>
> I noticed an extra void argument that didn't exist
> tagged on the end.
>
> I then noticed other code doing this (which I copied:)
>
> for ( arg =3D TYPE_ARG_TYPES ( func_type);
>         arg !=3D NULL && arg !=3D void_list_node;
>         arg =3D TREE_CHAIN ( arg))
>      {
>          .
>          .
>       }
>
> What is going on here???

Without a void_list_node on the end it's a variadic function

> Thanks,
>
> Gary
>
>
>
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