Re: -no-undefined option

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-no-undefined option
\ Lin George (13 Dec 2006)
. \ Ian Lance Taylor (13 Dec 2006)
. \ Lin George (14 Dec 2006)
. . \ Ian Lance Taylor (14 Dec 2006)
. \ Lin George (14 Dec 2006)
. . \ Ian Lance Taylor (14 Dec 2006)
. \ Lin George (14 Dec 2006)
. . \ Ian Lance Taylor (14 Dec 2006)
. \ Lin George (15 Dec 2006)

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Subject:	Re: -no-undefined option
Group:	Gcc-help
From:	Lin George
Date:	15 Dec 2006

Thanks Ian buddy. I have post my question to binutils mail list now. Hope we have a happy discussion there. :-)

regards,
George

----- Original Message ----
From: Ian Lance Taylor <iant>
To: Lin George <george4academic>
Cc: gcc-help
Sent: Thursday, December 14, 2006 11:33:57 PM
Subject: Re: -no-undefined option

Lin George <george4academic> writes:

> Thanks Ian! In most cases, I do not notice people to add this option
> when building a shared library. I think it is high risk (when
> running), since if this option is not added, linker will never try
> to resolve whether the referred functions are implemented actually
> (exported) by other modules. Do you agree? Any comments?

Many shared libraries depend upon other shared libraries. Note that
by default the linker will warn about undefined symbols. If you use
-no-undefined, that warning will become an error.

If you want to change the default, please raise the issue on
binutils.

> BTW: now I am wondering if this option is not added to linker when
> building a shared library, will linker do any sanity checking? I
> think in this situation, whether referred function is exported by
> other module is not checked. But what sanity points are checked in
> this situation? Thanks again.

I'm sorry, I don't understand this question. And it should probably
go to binutils anyhow.

Ian

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