Seen on Ubuntu 9.10. regehr@john-home:~/volatile/bugs/tmp253$ current-gcc -O2 small.c small.c: In function ‘bar’: small.c:16:1: error: definition in block 7 does not dominate use in block 2 for SSA_NAME: l_23_17 in statement: l_23_2 = PHI <l_23_17(7), l_23_17(2)> PHI argument l_23_17 for PHI node l_23_2 = PHI <l_23_17(7), l_23_17(2)> small.c:16:1: internal compiler error: verify_ssa failed Please submit a full bug report, with preprocessed source if appropriate. See <http://gcc.gnu.org/bugs.html> for instructions. regehr@john-home:~/volatile/bugs/tmp253$ current-gcc -v Using built-in specs. COLLECT_GCC=current-gcc COLLECT_LTO_WRAPPER=/home/regehr/z/tmp/gcc-r155838-install/libexec/gcc/i686-pc-linux-gnu/4.5.0/lto-wrapper Target: i686-pc-linux-gnu Configured with: ../configure --with-libelf=/usr/local --enable-lto --prefix=/home/regehr/z/tmp/gcc-r155838-install --program-prefix=r155838- --enable-languages=c,c++ Thread model: posix gcc version 4.5.0 20100112 (experimental) (GCC) regehr@john-home:~/volatile/bugs/tmp253$ cat small.c static signed char foo (signed char si1, unsigned char si2) { return (si1 ^ si2) & (-si2 ^ si2) ? : si1 - si2; } struct S0 { }; unsigned char g_21; struct S0 g_34; void bar (unsigned char p_20) { unsigned char *l_22 = &g_21; unsigned char l_23 = 0; struct S0 *l = &g_34; goto lbl_42; for (; l_23; l_23 = foo (l_23, 1)) { for (p_20 = 0; 0; p_20 = foo (p_20, 1)) lbl_42:; (l == &g_34) ? 0 : ""; lbl_85:*l_22 = p_20; } goto lbl_85; }
It is caused by revision 149199: http://gcc.gnu.org/ml/gcc-cvs/2009-07/msg00076.html
This: /* We are sure that for every live PHI we are seeing control dependent BB. This means that we can look up the end of control dependent path leading to the PHI itself. */ FOR_EACH_EDGE (e2, ei, post_dom_bb->preds) if (e2 != e && dominated_by_p (CDI_POST_DOMINATORS, e->src, e2->src)) break; is broken. We redirect lbl_42 -> bb 4 to bb 7 in <bb 2>: lbl_42: p_20.0_8 = (signed char) p_20_7(D); D.2736_9 = (int) p_20.0_8; D.2769_26 = D.2736_9 ^ 1; D.2766_31 = D.2769_26 & -2; if (D.2766_31 != 0) goto <bb 4>; else goto <bb 5>; <bb 4>: D.2763_32 = (signed char) D.2766_31; goto <bb 6>; <bb 5>: D.2764_34 = p_20_7(D) + 255; D.2763_35 = (signed char) D.2764_34; <bb 6>: # D.2763_36 = PHI <D.2763_32(4), D.2763_35(5)> p_20_11 = (unsigned char) D.2763_36; <bb 7>: # l_23_2 = PHI <l_23_17(12), 0(6)> but instead of finding 6 -> 7 we find 12 -> 7, a loop backedge. We have to find the correct path leading to the PHI node in case there is an ambiguity like here. Not sure if excluding back edges is enough, but certainly a back edge cannot be the correct one? Well. I'm testing a patch.
Doesn't work. FAIL: gcc.c-torture/execute/20010129-1.c compilation, -O3 -fomit-frame-pointer (internal compiler error)
Testing sth else.
Fixed.
Subject: Bug 42717 Author: rguenth Date: Wed Jan 20 12:30:15 2010 New Revision: 156076 URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=156076 Log: 2010-01-20 Richard Guenther <rguenther@suse.de> PR tree-optimization/42717 * tree-ssa-dce.c (get_live_post_dom): Remove. (forward_edge_to_pdom): Take an arbitrary edge to copy degenerate PHI args from. (remove_dead_stmt): Use the first post-dominator even if it does not contain live statements as redirection destination. * gcc.c-torture/compile/pr42717.c: New testcase. Added: trunk/gcc/testsuite/gcc.c-torture/compile/pr42717.c Modified: trunk/gcc/ChangeLog trunk/gcc/testsuite/ChangeLog trunk/gcc/tree-ssa-dce.c
Subject: Bug 42717 Author: hjl Date: Sun Feb 7 04:41:22 2010 New Revision: 156562 URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=156562 Log: Backport testcases from mainline to 4.4. 2010-02-06 H.J. Lu <hongjiu.lu@intel.com> Backport from mainline: 2010-02-05 Dodji Seketeli <dodji@redhat.com> PR c++/42915 * g++.dg/other/crash-9.C: New test. 2010-02-03 Jason Merrill <jason@redhat.com> PR c++/40138 * g++.dg/ext/builtin11.C: New. 2010-02-03 Richard Guenther <rguenther@suse.de> PR tree-optimization/42944 * gcc.dg/errno-1.c: New testcase. 2010-02-03 Richard Guenther <rguenther@suse.de> PR middle-end/42927 * gcc.c-torture/compile/pr42927.c: New testcase. 2010-01-29 Dodji Seketeli <dodji@redhat.com> PR c++/42758 PR c++/42634 PR c++/42336 PR c++/42797 PR c++/42880 * g++.dg/other/crash-5.C: New test. * g++.dg/other/crash-7.C: New test. * g++.dg/other/crash-8.C: New test. 2010-01-28 Uros Bizjak <ubizjak@gmail.com> PR target/42891 * gcc.target/i386/pr42891.c: New test. 2010-01-28 Richard Guenther <rguenther@suse.de> PR middle-end/42883 * g++.dg/torture/pr42883.C: New testcase. 2010-01-28 Michael Matz <matz@suse.de> * gcc.target/i386/pr42881.c: New test. 2010-01-28 Dodji Seketeli <dodji@redhat.com> PR c++/42713 PR c++/42820 * g++.dg/template/typedef27.C: New test case. * g++.dg/template/typedef28.C: New test case. 2010-01-27 Jakub Jelinek <jakub@redhat.com> PR middle-end/42874 * gcc.dg/vla-22.c: New test. 2010-01-26 Richard Guenther <rguenther@suse.de> PR tree-optimization/42250 * gcc.dg/pr42250.c: New testcase. 2010-01-25 Tobias Burnus <burnus@net-b.de> PR fortran/42858 * gfortran.dg/generic_21.f90: New test. 2010-01-21 Martin Jambor <mjambor@suse.cz> PR tree-optimization/42585 * gcc.dg/tree-ssa/pr42585.c: New test. 2010-01-20 Alexandre Oliva <aoliva@redhat.com> PR debug/42715 * gcc.dg/pr42715.c: New. 2010-01-20 Richard Guenther <rguenther@suse.de> PR tree-optimization/42717 * gcc.c-torture/compile/pr42717.c: New testcase. 2010-01-19 Paul Thomas <pault@gcc.gnu.org> PR fortran/42783 * gfortran.dg/bounds_check_15.f90 : New test. 2010-01-18 Dodji Seketeli <dodji@redhat.com> PR c++/42766 * g++.dg/conversion/op6.C: New test. 2010-01-18 Richard Guenther <rguenther@suse.de> PR tree-optimization/42781 * gfortran.fortran-torture/compile/pr42781.f90: New testcase. 2010-01-17 Richard Guenther <rguenther@suse.de> PR middle-end/42248 * gcc.c-torture/execute/pr42248.c: New testcase. 2010-01-17 Janus Weil <janus@gcc.gnu.org> PR fortran/42677 * gfortran.dg/interface_assignment_5.f90: New test. 2010-01-15 Richard Guenther <rguenther@suse.de> PR middle-end/42739 * g++.dg/torture/pr42739.C: New testcase. 2010-01-14 Jerry DeLisle <jvdelisle@gcc.gnu.org> PR fortran/42684 * gfortran.dg/interface_31.f90: New test. 2010-01-14 Martin Jambor <mjambor@suse.cz> PR tree-optimization/42706 * gcc.dg/ipa/pr42706.c: New testcase. 2010-01-14 Martin Jambor <mjambor@suse.cz> PR tree-optimization/42714 * g++.dg/torture/pr42714.C: New test. 2010-01-14 Alexander Monakov <amonakov@ispras.ru> PR rtl-optimization/42388 * gcc.dg/pr42388.c: New. 2010-01-14 Alexander Monakov <amonakov@ispras.ru> PR rtl-optimization/42294 * gfortran.dg/pr42294.f: New. 2010-01-14 Ira Rosen <irar@il.ibm.com> PR tree-optimization/42709 * gcc.dg/vect/pr42709.c: New test. 2010-01-13 Richard Guenther <rguenther@suse.de> PR tree-optimization/42730 * gcc.c-torture/compile/pr42730.c: New testcase. 2010-01-13 Martin Jambor <mjambor@suse.cz> PR tree-optimization/42704 * g++.dg/torture/pr42704.C: New test. 2010-01-13 Martin Jambor <mjambor@suse.cz> PR tree-optimization/42703 * gcc.c-torture/compile/pr42703.c: New test. 2010-01-13 Richard Guenther <rguenther@suse.de> PR tree-optimization/42705 * gcc.c-torture/compile/pr42705.c: New testcase. 2010-01-13 Richard Guenther <rguenther@suse.de> PR middle-end/42716 * gcc.c-torture/compile/pr42716.c: New testcase. 2010-01-12 Joseph Myers <joseph@codesourcery.com> PR c/42708 * gcc.c-torture/compile/pr42708-1.c: New test. 2010-01-09 Alexandre Oliva <aoliva@redhat.com> PR middle-end/42363 * gcc.dg/torture/pr42363.c: New. 2010-01-09 Alexandre Oliva <aoliva@redhat.com> PR debug/42604 PR debug/42395 * gcc.dg/vect/pr42604.c: New. * gcc.dg/vect/pr42395.c: New. 2010-01-09 Richard Guenther <rguenther@suse.de> PR middle-end/42512 * gcc.c-torture/execute/pr42512.c: New testcase. Added: branches/gcc-4_4-branch/gcc/testsuite/g++.dg/conversion/op6.C - copied unchanged from r156561, trunk/gcc/testsuite/g++.dg/conversion/op6.C branches/gcc-4_4-branch/gcc/testsuite/g++.dg/ext/builtin11.C - copied unchanged from r156561, trunk/gcc/testsuite/g++.dg/ext/builtin11.C branches/gcc-4_4-branch/gcc/testsuite/g++.dg/other/crash-5.C - copied unchanged from r156561, trunk/gcc/testsuite/g++.dg/other/crash-5.C branches/gcc-4_4-branch/gcc/testsuite/g++.dg/other/crash-7.C - copied unchanged from r156561, trunk/gcc/testsuite/g++.dg/other/crash-7.C branches/gcc-4_4-branch/gcc/testsuite/g++.dg/other/crash-8.C - copied unchanged from r156561, trunk/gcc/testsuite/g++.dg/other/crash-8.C branches/gcc-4_4-branch/gcc/testsuite/g++.dg/other/crash-9.C - copied unchanged from r156561, trunk/gcc/testsuite/g++.dg/other/crash-9.C branches/gcc-4_4-branch/gcc/testsuite/g++.dg/template/typedef27.C - copied unchanged from r156561, trunk/gcc/testsuite/g++.dg/template/typedef27.C branches/gcc-4_4-branch/gcc/testsuite/g++.dg/template/typedef28.C - copied unchanged from r156561, trunk/gcc/testsuite/g++.dg/template/typedef28.C branches/gcc-4_4-branch/gcc/testsuite/g++.dg/torture/pr42704.C - copied unchanged from r156561, trunk/gcc/testsuite/g++.dg/torture/pr42704.C branches/gcc-4_4-branch/gcc/testsuite/g++.dg/torture/pr42714.C - copied unchanged from r156561, trunk/gcc/testsuite/g++.dg/torture/pr42714.C branches/gcc-4_4-branch/gcc/testsuite/g++.dg/torture/pr42739.C - copied unchanged from r156561, trunk/gcc/testsuite/g++.dg/torture/pr42739.C branches/gcc-4_4-branch/gcc/testsuite/g++.dg/torture/pr42883.C - copied unchanged from r156561, trunk/gcc/testsuite/g++.dg/torture/pr42883.C branches/gcc-4_4-branch/gcc/testsuite/gcc.c-torture/compile/pr42703.c - copied unchanged from r156561, trunk/gcc/testsuite/gcc.c-torture/compile/pr42703.c branches/gcc-4_4-branch/gcc/testsuite/gcc.c-torture/compile/pr42705.c - copied unchanged from r156561, trunk/gcc/testsuite/gcc.c-torture/compile/pr42705.c branches/gcc-4_4-branch/gcc/testsuite/gcc.c-torture/compile/pr42708-1.c - copied unchanged from r156561, trunk/gcc/testsuite/gcc.c-torture/compile/pr42708-1.c branches/gcc-4_4-branch/gcc/testsuite/gcc.c-torture/compile/pr42716.c - copied unchanged from r156561, trunk/gcc/testsuite/gcc.c-torture/compile/pr42716.c branches/gcc-4_4-branch/gcc/testsuite/gcc.c-torture/compile/pr42717.c - copied unchanged from r156561, trunk/gcc/testsuite/gcc.c-torture/compile/pr42717.c branches/gcc-4_4-branch/gcc/testsuite/gcc.c-torture/compile/pr42730.c - copied unchanged from r156561, trunk/gcc/testsuite/gcc.c-torture/compile/pr42730.c branches/gcc-4_4-branch/gcc/testsuite/gcc.c-torture/compile/pr42927.c - copied unchanged from r156561, trunk/gcc/testsuite/gcc.c-torture/compile/pr42927.c branches/gcc-4_4-branch/gcc/testsuite/gcc.c-torture/execute/pr42248.c - copied unchanged from r156561, trunk/gcc/testsuite/gcc.c-torture/execute/pr42248.c branches/gcc-4_4-branch/gcc/testsuite/gcc.c-torture/execute/pr42512.c - copied unchanged from r156561, trunk/gcc/testsuite/gcc.c-torture/execute/pr42512.c branches/gcc-4_4-branch/gcc/testsuite/gcc.dg/errno-1.c - copied unchanged from r156561, trunk/gcc/testsuite/gcc.dg/errno-1.c branches/gcc-4_4-branch/gcc/testsuite/gcc.dg/ipa/pr42706.c - copied unchanged from r156561, trunk/gcc/testsuite/gcc.dg/ipa/pr42706.c branches/gcc-4_4-branch/gcc/testsuite/gcc.dg/pr42250.c - copied unchanged from r156561, trunk/gcc/testsuite/gcc.dg/pr42250.c branches/gcc-4_4-branch/gcc/testsuite/gcc.dg/pr42388.c - copied unchanged from r156561, trunk/gcc/testsuite/gcc.dg/pr42388.c branches/gcc-4_4-branch/gcc/testsuite/gcc.dg/pr42715.c - copied unchanged from r156561, trunk/gcc/testsuite/gcc.dg/pr42715.c branches/gcc-4_4-branch/gcc/testsuite/gcc.dg/torture/pr42363.c - copied unchanged from r156561, trunk/gcc/testsuite/gcc.dg/torture/pr42363.c branches/gcc-4_4-branch/gcc/testsuite/gcc.dg/tree-ssa/pr42585.c - copied unchanged from r156561, trunk/gcc/testsuite/gcc.dg/tree-ssa/pr42585.c branches/gcc-4_4-branch/gcc/testsuite/gcc.dg/vect/pr42395.c - copied unchanged from r156561, trunk/gcc/testsuite/gcc.dg/vect/pr42395.c branches/gcc-4_4-branch/gcc/testsuite/gcc.dg/vect/pr42604.c - copied unchanged from r156561, trunk/gcc/testsuite/gcc.dg/vect/pr42604.c branches/gcc-4_4-branch/gcc/testsuite/gcc.dg/vect/pr42709.c - copied unchanged from r156561, trunk/gcc/testsuite/gcc.dg/vect/pr42709.c branches/gcc-4_4-branch/gcc/testsuite/gcc.dg/vla-22.c - copied unchanged from r156561, trunk/gcc/testsuite/gcc.dg/vla-22.c branches/gcc-4_4-branch/gcc/testsuite/gcc.target/i386/pr42881.c - copied unchanged from r156561, trunk/gcc/testsuite/gcc.target/i386/pr42881.c branches/gcc-4_4-branch/gcc/testsuite/gcc.target/i386/pr42891.c - copied unchanged from r156561, trunk/gcc/testsuite/gcc.target/i386/pr42891.c branches/gcc-4_4-branch/gcc/testsuite/gfortran.dg/bounds_check_15.f90 - copied unchanged from r156561, trunk/gcc/testsuite/gfortran.dg/bounds_check_15.f90 branches/gcc-4_4-branch/gcc/testsuite/gfortran.dg/generic_21.f90 - copied unchanged from r156561, trunk/gcc/testsuite/gfortran.dg/generic_21.f90 branches/gcc-4_4-branch/gcc/testsuite/gfortran.dg/interface_31.f90 - copied unchanged from r156561, trunk/gcc/testsuite/gfortran.dg/interface_31.f90 branches/gcc-4_4-branch/gcc/testsuite/gfortran.dg/interface_assignment_5.f90 - copied unchanged from r156561, trunk/gcc/testsuite/gfortran.dg/interface_assignment_5.f90 branches/gcc-4_4-branch/gcc/testsuite/gfortran.dg/pr42294.f - copied unchanged from r156561, trunk/gcc/testsuite/gfortran.dg/pr42294.f branches/gcc-4_4-branch/gcc/testsuite/gfortran.fortran-torture/compile/pr42781.f90 - copied unchanged from r156561, trunk/gcc/testsuite/gfortran.fortran-torture/compile/pr42781.f90 Modified: branches/gcc-4_4-branch/gcc/testsuite/ChangeLog