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Re: gcc bug/quirk with left shifts on i386 family.
- To: Peter Wemm <peter at netplex dot com dot au>
- Subject: Re: gcc bug/quirk with left shifts on i386 family.
- From: Alexandre Oliva <aoliva at redhat dot com>
- Date: 04 Jan 2001 17:52:18 -0200
- Cc: gcc-bugs at gcc dot gnu dot org
- Organization: GCC Team, Red Hat
- References: <200101041915.f04JFFq10713@mobile.wemm.org>
On Jan 4, 2001, Peter Wemm <peter@netplex.com.au> wrote:
> I'm not sure if this is a real bug or one of those gray 'implementation
> defined' areas of the language
It's actually undefined behavior, which allows the compiler to choose
whatever it wants, even if it's not self-consistent in different
occurrences of the same expression. It could also format your hard
disk or start nethack. Or it could arrange for the resulting program
to do so :-)
If it were implementation-defined, behavior would have to be
consistent.
--
Alexandre Oliva Enjoy Guarana', see http://www.ic.unicamp.br/~oliva/
Red Hat GCC Developer aoliva@{cygnus.com, redhat.com}
CS PhD student at IC-Unicamp oliva@{lsd.ic.unicamp.br, gnu.org}
Free Software Evangelist *Please* write to mailing lists, not to me