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	Wed, 22 Apr 2026 14:34:37 +0000
Date: Wed, 22 Apr 2026 15:34:37 +0100
From: Al Viro <viro@zeniv.linux.org.uk>
To: Thorsten Blum <thorsten.blum@linux.dev>
Cc: Christian Brauner <brauner@kernel.org>, Jan Kara <jack@suse.cz>,
	linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] dcache: use QSTR() instead of QSTR_INIT()
Message-ID: <20260422143437.GI3518998@ZenIV>
References: <20260422123345.100436-2-thorsten.blum@linux.dev>
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Sender: Al Viro <viro@ftp.linux.org.uk>

On Wed, Apr 22, 2026 at 02:33:46PM +0200, Thorsten Blum wrote:
> Drop the hard-coded length arguments and use the simpler QSTR().

... which is not a constant expression.  NAK.

QSTR_INIT() is an initializer list for struct qstr; QSTR() is a
compound literal for the same.  IOW, its value is an anonymous
local variable with given contents.

C grammar allows both
	struct foo x = {.bar = y};
and
	struct foo x = (struct foo){.bar = y};
for auto variables, and compiler is able to figure out that they
are equivalent.  But the second form is not legal for the static-duration
variables.