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Date: Mon, 30 Nov 2015 11:47:34 +0800
From: Peter Xu <peterx@redhat.com>
Message-ID: <20151130034732.GA12255@pxdev.xzpeter.org>
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Subject: [Qemu-devel] question: about exec/poison.h
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To: qemu-devel@nongnu.org
Cc: Peter Xu <peterx@redhat.com>

Hi, all,

I met one problem when trying to add a new public function in dump.h
named "dump_state_get_global" and using it in hmp.c. What I got is
something like:

In file included from /root/git/qemu/hmp.c:35:0:
/root/git/qemu/include/sysemu/dump.h:26:34: error: attempt to use poisoned "TARGET_PAGE_BITS"
     (((unsigned long long)(X) >> TARGET_PAGE_BITS) - ARCH_PFN_OFFSET)

I did a quick look on the poison.h file, seeing that it should be
used to avoid using arch-depentent macros in arch-independent
codes. That's cool. However, that's also problem to me.

The problem is: First of all, dump itself is arch
dependent. Meanwhile, hmp.c is not. Also, what I am trying to add is
arch indepentent too (just like hmp.c). Now if I include "dump.h" in
hmp.c to use that function, I may encounter the error message.

I got one idea, which is to split dump.h into two header files:
dump.h and dump-arch-indep.h (the latter name could be of course
shorter). So that I can move arch independent declarations into that
new header file and use it in hmp.h. Not sure whether this is the
good one to go.

Does anyone have suggestion on what I should do?

Thanks in advance!
Peter