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Date: Mon, 19 Jan 2026 08:28:02 +0100
From: Christoph Hellwig <hch@lst.de>
To: Gao Xiang <hsiangkao@linux.alibaba.com>
Cc: Hongbo Li <lihongbo22@huawei.com>, chao@kernel.org, brauner@kernel.org,
	djwong@kernel.org, amir73il@gmail.com,
	linux-fsdevel@vger.kernel.org, linux-erofs@lists.ozlabs.org,
	linux-kernel@vger.kernel.org, Christoph Hellwig <hch@lst.de>
Subject: Re: [PATCH v15 2/9] erofs: decouple `struct erofs_anon_fs_type`
Message-ID: <20260119072802.GA2562@lst.de>
References: <20260116095550.627082-1-lihongbo22@huawei.com> <20260116095550.627082-3-lihongbo22@huawei.com> <20260116153829.GB21174@lst.de> <c2f3f8bd-6319-4f5a-92cf-7717fa0c0972@huawei.com> <e4a45ea4-a0e9-4b8e-ab8b-b4dbb6a2ba21@linux.alibaba.com>
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On Mon, Jan 19, 2026 at 09:44:59AM +0800, Gao Xiang wrote:
> But I'm not sure if there is a case as `#if defined() || defined()`,
> it seems it cannot be simply replaced with `#ifdef`.

They can't.  If you have multiple statements compined using operators
you need to use #if and defined().