From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1EB0A44DB73 for ; Wed, 27 May 2026 17:58:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779904714; cv=none; b=X6mlb/T62SkOsEBGYG6MgILQm6L8Bm2krtOkECUceeuXEIMylb6+qMpqGk9uteKfemL73x6xo/7H3QfMeNJn1nFdVPNhXD9nUEl0mBQMtAKmgXGgeEwo4QAaqCz7LEFcKQsZkK0fWyAggn+9pBrGAXVYSpXwaf1eG/3Kq9WgkUc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779904714; c=relaxed/simple; bh=bPToN+UDiJpY5uAJOa2XaiHvHWK+0RbEEy/q+pU23xk=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Br47brAPylx11YVwPzN2M8w0gQvPnOHir0cc9jTz30VheuL6tTU2yUOdwk3WZIIp4jXSU9TAHgdK89844Zc/fy9KrDkCnxztZKnjJgkuf6tNQJPp05gYNq9l5t5ZNhh4+Qb7Zxo7el1eUEWQxWRqxzKT80Mqpc0hGf8jdRWTSOc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=DK8t21x/; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="DK8t21x/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1D0391F000E9; Wed, 27 May 2026 17:58:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1779904712; bh=aRig4eFVWbWZ/v0nT12CQcjcjB6msQnQQYaUtCOQPnM=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=DK8t21x/weLgqmfU3pB7DEEYWzT4ARsgd+0i/BWhMSrdPvfevlzw4hrYwCM9ARzmS sFkS75+XDSZC0lwkXYvmlG34X4SpX4d/y0km998fjw1D8QiuTWkJt64LCx/F/R3DIa oo/ShpRfiMAqKU3C8oWfsY7U/HNGRaxM7opvGzWLmMq4v+vTlW7rysbvMvyi4RMElO d7hlb37Qre31GL4rtGUrEISyJcii5dDKpqx244EmPGWgmRjIFSx7eNhNSjLH22wJpR aGZcwwJzJM5uliSGlrfiWWD9QHcEl8rxprruP3fkE6VyO/OdkRoBnBRuW/u+YOnuXA Nt018B1oPZQ4Q== Date: Wed, 27 May 2026 19:58:28 +0200 From: Alejandro Colomar To: "Michael Kerrisk (man7.org)" Cc: linux-man Subject: Re: Mangled function prototypes (phantom arguments) Message-ID: References: Precedence: bulk X-Mailing-List: linux-man@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="xpvqyofzahcmskut" Content-Disposition: inline In-Reply-To: --xpvqyofzahcmskut Content-Type: text/plain; protected-headers=v1; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable From: Alejandro Colomar To: "Michael Kerrisk (man7.org)" Cc: linux-man Subject: Re: Mangled function prototypes (phantom arguments) Message-ID: References: MIME-Version: 1.0 In-Reply-To: Hi Michael, On 2026-05-27T18:46:06+0200, Michael Kerrisk (man7.org) wrote: > Hello Alex, >=20 > Thanks for responding. >=20 > > > The problems have all resulted in prototypes adding a phantom first > > > argument. See for example this prototype from read.2: > > > > > > ssize_t read(size_t count; > > > int fd, void buf[count], size_t count); > > > > This is valid C (except for the array of void, but that's a separate > > topic). >=20 > As we see, I'm not keeping up with my C :-). To be fair, this is a very little-known feature (even though it's a very old one). I (and a few others) are trying to make it more well known, as it's quite interesting. >=20 > Is this a GNU extension? Or part of the standard? Or an upcoming part > of the standard? It is a very old GNU extension. For decades, almost nobody had been interested in it (I've never seen it used in the wild). One or two years ago, we started discussing it in the C Committee; several of us want it to be standard. However, Clang is vetoing it. Cheers, Alex >=20 > Thanks, >=20 > Michael --=20 --xpvqyofzahcmskut Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEES7Jt9u9GbmlWADAi64mZXMKQwqkFAmoXML8ACgkQ64mZXMKQ wqlVfBAAvq2LRhaAYWmXaYmM8jaZYPqZbQ971GEmHxOYzpQ+nTF1npmekg00G92X PsXIQNA8Fbpb2gMe9euukL7AcDaSK55pr8Ku8sC3dTykIRiUSfBSW35dPzYVuyBd vkB/x+Op00wyOOs3D0irIIIcKpam2JAEZooU4fdSgmSOMl7J3aZha0IbMRLUofuz 4jtaH1YwFgWPjFa/sQ1txmZp9JZ4Vhs7+7EJR3Z1p7q4yK6FvhPVgswr5kMtzmaP Ii5T9oiaNEaFmTwladCa/AvY6IHBHxIOSjKMaljpVnxEagcGpMdNhtgpoIr4pMMA hNSnrPgEQnsAJ+0bKxHQTRamfKegUtc9w/lAF81BaB/nHnIBpZPRF1US1Zk+Po+v bzZoP2aq72Wgu1vr74PKAm8IYNly/FNW808Wo8L59mgGO36ORjKeQTMKCSIYABxK lWq+avodxd8x2LoSiumtuSmDE4omNO/gJnJAZ/B+SEdSUKIugZrtlNWMdf4I3Wbl Fe8DcuO9V3a++Kdv/Ky/gT5FkKugqSyzUwrThHf83JyJZU5WjZRD/xlKYl5JVrkM mcBcIM/1r/PJxzT3lnIfw8tLIJe22NH+nf46OVD9qid1vVc5ViGdzGRfqCCD+ohZ f6AX1TtThB1HIZj9Pk7JdE3G4+Rh5ie1zz5fGwddxhHqes8FNWw= =4yy0 -----END PGP SIGNATURE----- --xpvqyofzahcmskut--