Path: utzoo!telly!ddsw1!lll-winken!killer!texbell!bigtex!milano!cs.utexas.edu!tut.cis.ohio-state.edu!ATHENA.MIT.EDU!raeburn
From: raeburn@ATHENA.MIT.EDU (Ken Raeburn)
Newsgroups: gnu.gcc.bug
Subject: gcc 1.32 (vax) aborts on asm with conflicting constraints
Message-ID: <8812280402.AA00784@PROMETHEUS.MIT.EDU>
Date: 28 Dec 88 04:02:15 GMT
Sender: daemon@tut.cis.ohio-state.edu
Distribution: gnu
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Lines: 23


Although the construct below isn't valid (*ip++ and ip have to match
because of the "0" constraint -- this is the result of only partly
undoing a workaround for a bug in 1.31), the compiler should print a
warning rather than dumping core.  (This is both with and without
optimization.)

-- Ken

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

extern int i, *jp, j;
foo ()
{
	volatile int *ip = jp;
	for (i=0; i < j ; i++) {
		asm volatile ("extzv %1,$1,%2,%0"
			      : "g" (*ip++)
			      : "g" (i), "g" (*jp), "0" (ip));
	}
}

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~