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To: Richard Earnshaw <rearnsha@gcc.gnu.org>
Cc: Julian Brown <julian@codesourcery.com>, binutils@sources.redhat.com
Subject: Re: [PATCH] Indicate dependency on personality routines for ARM EHABI
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	<1107967723.4376.9.camel@pc960.cambridge.arm.com>
From: Ian Lance Taylor <ian@airs.com>
Date: Wed, 09 Feb 2005 17:42:00 -0000
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Richard Earnshaw <rearnsha@gcc.gnu.org> writes:

> > More generally, I think it's kind of dubious to use a zero reloc to
> > mean anything at all.  And why do you need a relocation entry?  Why is
> > it not sufficient to enter the symbol in the symbol table as an
> > undefined symbol?  Is the use of a zero reloc mandated by the ARM ABI?
> 
> Because the unwind module only weakly links to the personality modules
> (but it is the one that ends up calling them).
> 
> The module that needs the unwinding has to provide the strong reference
> to ensure that it gets included in the link set.
> 
> Doing it this way ensures that only personality modules that are needed
> get included in the final image.

I would expect a strong undefined symbol would achieve the same effect
without the relocation entry.

But if the ABI requires the relocation entry, that is fine.

Ian