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Date: Sun, 26 Aug 2001 02:13:56 -0400
Message-Id: <200108260613.CAA28557@envy.delorie.com>
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From: DJ Delorie <dj AT delorie DOT com>
To: cwilson AT ece DOT gatech DOT edu
CC: binutils AT sources DOT redhat DOT com, cygwin AT cygwin DOT com
In-reply-to: <3B888D76.6090102@ece.gatech.edu> (message from Charles Wilson on
	Sun, 26 Aug 2001 01:47:34 -0400)
Subject: Re: [aida_s AT mx12 DOT freecom DOT ne DOT jp: A serious bug of "ld --enable-auto-import"]
References: <3B8884F6 DOT 80708 AT ece DOT gatech DOT edu> <200108260530 DOT BAA28221 AT envy DOT delorie DOT com> <3B888D76 DOT 6090102 AT ece DOT gatech DOT edu>


> Anyway, I'm confused.  The .o file already contains the "12" (actually, 
> 0c 00 00 00 in on-disk byte order), so gas has already done its work -- 
> properly.  The problem occurs during the linking step -- ld is ignoring 
> the offset stored within the opcode and is blindly stuffing in the 
> relocation address without adding the offset.

Ok, a couple of things:

In make_import_fixup in ld/emultempl/pe.em, it uses rel->addend
without also checking for the inline offset.  For formats that use an
inline addend, rel->addend may be zero.

Addends are very tricky in PE.  There's lots of comments about adding,
subtracting, adding, subtracting, etc, in various places in the code.

I don't think an import library *can* specify an offset to be added at
runtime.  From my understanding of the dll import/export system,
windows simply places the address of the thing being imported in the
location indicated.

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