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[Bug tree-optimization/33572] [4.3 Regression] wrong code with -O
- From: "rguenth at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>
- To: gcc-bugs at gcc dot gnu dot org
- Date: 27 Sep 2007 21:03:18 -0000
- Subject: [Bug tree-optimization/33572] [4.3 Regression] wrong code with -O
- References: <bug-33572-8535@http.gcc.gnu.org/bugzilla/>
- Reply-to: gcc-bugzilla at gcc dot gnu dot org
------- Comment #5 from rguenth at gcc dot gnu dot org 2007-09-27 21:03 -------
Confirmed. The reduced testcase gets optimized to
<bb 3>:
D.2145 = operator new (8);
<bb 4>:
((struct Foo *) D.2145)->_vptr.Foo = &_ZTV3Foo[2];
<bb 5>:
D.2147 ={v} 0B->_vptr.Foo;
OBJ_TYPE_REF(*D.2147;0B->0) (0B);
where dereferencing NULL obviously is bogus. After 038t.sdse2 everything
looks ok:
<bb 4>:
D.2124_3 = (struct Foo *) D.2145_2;
D.2124_3->_vptr.Foo ={v} &_ZTV3Foo[2];
goto <bb 6>;
<bb 5>:
deallocate (&v, 0B);
<bb 6>:
# foo$ptr_16 = PHI <foo$ptr_18(ab)(5), D.2124_3(4)>
foo$ptr_19(ab) = 0B;
D.2147_6 = foo$ptr_16->_vptr.Foo;
D.2148_7 = *D.2147_6;
but after apply inline it's wrong!?
<bb 3>:
D.2145_2 = operator new (8);
<bb 4>:
D.2124_3 = (struct Foo *) D.2145_2;
D.2124_3->_vptr.Foo ={v} &_ZTV3Foo[2];
<bb 5>:
# foo$ptr_16 = PHI <foo$ptr_18(ab)(2), D.2124_3(4)>
foo$ptr_19(ab) = 0B;
D.2147_6 = foo$ptr_19(ab)->_vptr.Foo;
D.2148_7 = *D.2147_6;
OBJ_TYPE_REF(D.2148_7;foo$ptr_19(ab)->0) (foo$ptr_19(ab));
goto <bb 7>;
--
rguenth at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |rguenth at gcc dot gnu dot
| |org
Status|WAITING |NEW
Component|c++ |tree-optimization
Ever Confirmed|0 |1
Keywords| |wrong-code
Last reconfirmed|0000-00-00 00:00:00 |2007-09-27 21:03:18
date| |
Summary|wrong code with -O |[4.3 Regression] wrong code
| |with -O
Target Milestone|--- |4.3.0
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33572