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From: Andrew Haley <aph@redhat.com>
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Date: Thu, 27 Nov 2003 10:31:00 -0000
To: "Zack Weinberg" <zack@codesourcery.com>
Cc: <gcc-patches@gcc.gnu.org>
Subject: Re: avoid unnecessary register saves for setjmp
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Zack Weinberg writes:

 > So by using the EH unwinder for longjmp we clean
 > up a nasty dark corner of the language.

Do we really?  The value is still undefined according to 7.13.2.1 Para
3; all we're doing is making a gcc extension that such values are
well-defined.

Andrew.