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From: Jonathan Wakely <jwakely.gcc@gmail.com>
Date: Fri, 5 Aug 2022 17:55:39 +0100
Message-ID: <CAH6eHdTs2HcjVTkha6irihRCoRvxAS6RtZu+g4_8h8AFojcuTw@mail.gmail.com>
Subject: Re: Reason for missing notes for incomplete-type errors in standard
 headers
To: Julian Lenz <j.j.lenz@swansea.ac.uk>
Cc: "gcc@gcc.gnu.org" <gcc@gcc.gnu.org>
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On Fri, 5 Aug 2022 at 17:39, Julian Lenz via Gcc <gcc@gcc.gnu.org> wrote:
>
> Hi everybody,
>
> TL;DR:
>
> What is the reason that `error: '<some class>' has incomplete type` does
> not give a note about where the forward declaration happened for
> standard library classes?

Probably because the declaration happens in a system header.

Does -Wsystem-headers change it?