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In-Reply-To: <d82c40a1-72de-aba1-67a3-60293b6cf34b@ispras.ru>
From: Rui Ueyama <rui314@gmail.com>
Date: Sun, 15 May 2022 19:52:42 +0800
Message-ID: <CACKH++ZXawavQzYkYMuwXk9+NkspJO2XuBgHnfeFXot8qHyYMA@mail.gmail.com>
Subject: Re: [PATCH] lto-plugin: add support for feature detection
To: Alexander Monakov <amonakov@ispras.ru>
Cc: =?UTF-8?Q?Martin_Li=C5=A1ka?= <mliska@suse.cz>, 
 GCC Patches <gcc-patches@gcc.gnu.org>, Jan Hubicka <hubicka@ucw.cz>
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On Sun, May 15, 2022 at 7:37 PM Alexander Monakov <amonakov@ispras.ru> wrote:
>
> On Sun, 15 May 2022, Rui Ueyama wrote:
>
> > > Can you simply restart the linker on first call to get_symbols_v2 instead?
> >
> > I could, but it may not be a safe timing to call exec(2). I believe we
> > are expected to call cleanup_hook after calling all_symbols_read_hook,
> > and it is not clear what will happen if we abruptly terminate and
> > restart the current process. For example, doesn't it leave temporary
> > files on disk?
>
> Regarding files, as far as I can tell, GCC plugin will leave a 'resolution file'
> on disk, but after re-exec it would recreate it anyway.

Does it recreate a temporary file with the same file name so that
there's no temporary file left on the disk after the linker finishes
doing LTO?