From: Tom Lane <tgl@sss.pgh.pa.us>
To: Thomas Munro <thomas.munro@gmail.com>
cc: Xuneng Zhou <xunengzhou@gmail.com>, exclusion@gmail.com,
        pgsql-bugs@lists.postgresql.org, Michael Paquier <michael@paquier.xyz>
Subject: Re: BUG #19006: Assert(BufferIsPinned) in BufferGetBlockNumber() is
 triggered for forwarded buffer
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Comments: In-reply-to Thomas Munro <thomas.munro@gmail.com>
	message dated "Tue, 05 Aug 2025 16:29:17 +1200"
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Date: Tue, 05 Aug 2025 00:43:06 -0400
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Thomas Munro <thomas.munro@gmail.com> writes:
> Here's my proposed fix.  Great reproducer, Alexander, thanks!

I've not looked at the issue actually being fixed, but a drive-by
comment: these loops

+	for (int i =3D 0; i < stream->forwarded_buffers; ++i)
+		Assert(BufferGetBlockNumber(stream->buffers[stream->next_buffer_index +=
 i]) =3D=3D
+			   stream->pending_read_blocknum + i);

should be wrapped in "#ifdef USE_ASSERT_CHECKING".  Maybe the
compiler is smart enough to throw away the useless looping logic
in a production build, or maybe it isn't.

			regards, tom lane