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From: "Richard Guenther" <richard.guenther@gmail.com>
To: gcc-patches@gcc.gnu.org, zadeck@naturalbridge.com
Subject: Re: [lto] set alias info, poorly
Date: Fri, 07 Dec 2007 10:47:00 -0000	[thread overview]
Message-ID: <84fc9c000712070247g6ac73f01m94e71acfdac039c1@mail.gmail.com> (raw)
In-Reply-To: <20071206222919.GS14706@codesourcery.com>

On Dec 6, 2007 11:29 PM, Nathan Froyd <froydnj@codesourcery.com> wrote:
> First, the good news about this patch: it fixes a few failing testcases.
>
> The bad news is that it does it with a very heavy hammer.  We say that
> every type can alias every other type.  Obviously this wreaks havoc with
> all the clever alias analysis that has gone into GCC over the years.
>
> There are better, cleverer, more involved ways that you could fix this.
> But this demonstrably works right now.  Ideas on what to do in the
> future welcome.

I believe we have to write out the alias sets and the conflict map and at the
point we combine types of different translation units we have to merge the
alias sets and conflict maps properly.

Or not rely on TBAA for LTO, which is what your patch does (so I guess for
completeness you should disable strict aliasing as well).

Richard.

  reply	other threads:[~2007-12-07 10:47 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-12-06 22:29 Nathan Froyd
2007-12-07 10:47 ` Richard Guenther [this message]
2007-12-07 10:59   ` Jakub Jelinek
2007-12-10 13:55     ` Kenneth Zadeck
2007-12-10 19:55       ` Toon Moene
2007-12-10 20:02         ` Kenneth Zadeck
2007-12-10 20:09           ` Richard Guenther
2007-12-10 20:49             ` Kenneth Zadeck
2007-12-10 21:00               ` Richard Guenther

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