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From:   Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Date:   Mon, 19 Apr 2021 23:03:23 +0200
Message-ID: <CANiq72kEUEskKC=qA5q1ZiAJC9KKUcndVh6iZx_vJ1P=injF-g@mail.gmail.com>
Subject: Re: [PATCH 04/13] Kbuild: Rust support
To:     Matthew Wilcox <willy@infradead.org>
Cc:     dsterba@suse.cz, Peter Zijlstra <peterz@infradead.org>,
        Miguel Ojeda <ojeda@kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        rust-for-linux <rust-for-linux@vger.kernel.org>,
        Linux Kbuild mailing list <linux-kbuild@vger.kernel.org>,
        Linux Doc Mailing List <linux-doc@vger.kernel.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Alex Gaynor <alex.gaynor@gmail.com>,
        Geoffrey Thomas <geofft@ldpreload.com>,
        Finn Behrens <me@kloenk.de>,
        Adam Bratschi-Kaye <ark.email@gmail.com>,
        Wedson Almeida Filho <wedsonaf@google.com>,
        Michael Ellerman <mpe@ellerman.id.au>
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On Mon, Apr 19, 2021 at 10:18 PM Matthew Wilcox <willy@infradead.org> wrote:
>
> Yes, I agree, we need a better story for name mangling.
> My proposal is that we store a pretty name which matches the source
> (eg rust_binder::range_alloc) and a sha1 of the mangled symbol
> (40 bytes of uninteresting hex).  Symbol resolution is performed against
> the sha1.  Printing is of the pretty name.  It should be obvious from
> the stack trace which variant of a function is being called, no?

If the pretty name is only `rust_binder::range_alloc`, that would not
be enough, since (in this case) that is a module name (i.e. the
namespace of the `DescriptorState` type). The function being called
here is `fmt` (the one outside the `<>`), which is a method of the
`Debug` trait.

We could perhaps reduce this down to:

    rust_binder::range_alloc::DescriptorState::fmt

without much ambiguity (in most cases).

Cheers,
Miguel