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Date: Sun, 31 Mar 2002 03:42:20 -0500 (EST)
From: Alexander Viro <viro@math.psu.edu>
To: Andrew Morton <akpm@zip.com.au>
cc: "David S. Miller" <davem@redhat.com>, tim@birdsnest.maths.tcd.ie,
        linux-kernel@vger.kernel.org
Subject: Re: linux-2.5.7
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On Sun, 31 Mar 2002, Andrew Morton wrote:

> Could you remind us what problem this is solving?  The
> #ifdef approach seemed reasonable and there's no indication
> here why weak linkage is needed.

The thing we want here _is_ weak linkage - "return -ENOSYS unless
you have the real thing".  You can emulate that with ifdefs,
but that's what it is - emulation.  IOW, what we want actually
belongs to linker, not compiler.

When file looks like

#ifdef FOO
<lots of stuff>
<function calling that stuff>
#else
<make that function an equivalent of sys_ni_syscall()>
#endif

we are really talking about "make it an alias of sys_ni_syscall() and let
<all this stuff> override that".

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