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Date:   Sun, 17 Sep 2023 17:07:18 +0200
From:   Thomas =?utf-8?Q?Wei=C3=9Fschuh?= <linux@weissschuh.net>
To:     Willy Tarreau <w@1wt.eu>
Cc:     Paul Walmsley <paul.walmsley@sifive.com>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        Albert Ou <aou@eecs.berkeley.edu>,
        Shuah Khan <shuah@kernel.org>, linux-kernel@vger.kernel.org,
        linux-riscv@lists.infradead.org, linux-kselftest@vger.kernel.org
Subject: Re: [PATCH 2/4] tools/nolibc: avoid unused parameter warnings for
 ENOSYS fallbacks
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References: <20230914-nolibc-syscall-nr-v1-0-e50df410da11@weissschuh.net>
 <20230914-nolibc-syscall-nr-v1-2-e50df410da11@weissschuh.net>
 <20230917025851.GE9646@1wt.eu>
 <2bd688b7-5f1b-44ca-a41b-6e90dc3e8557@t-8ch.de>
 <20230917094827.GA11081@1wt.eu>
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On 2023-09-17 11:48:27+0200, Willy Tarreau wrote:
> [..]
> > Maybe the macro-equivalent of this?
> > 
> > static inline int __nolibc_enosys(...)
> > {
> > 	return -ENOSYS;
> > }
> > 
> > The only-vararg function unfortunately needs C23 so we can't use it.
> >
> > It's clear to the users that this is about ENOSYS and we don't need a
> > bunch of new macros similar.
> 
> I like it, I didn't think about varargs, it's an excellent idea! Let's
> just do simpler, start with a first arg "syscall_num" that we may later
> reuse for debugging, and just mark this one unused:
> 
>   static inline int __nolibc_enosys(int syscall_num, ...)
>   {
> 	(void)syscall_num;
>   	return -ENOSYS;
>   }

But which syscall_num to use, as the point of __nolibc_enosys() would be
that no syscall number is available and the defines are missing.

For debugging we could add a string argument, though.