https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65177
Bug ID: 65177 Summary: [5 Regression]: extend jump thread for finite state automata causes miscompilation Product: gcc Version: 5.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: tree-optimization Assignee: unassigned at gcc dot gnu.org Reporter: marxin at gcc dot gnu.org CC: spop at gcc dot gnu.org Hello. Starting with r218451, http://hmmer.janelia.org/ started to be miscompiled. Steps to reproduce: wget http://selab.janelia.org/software/hmmer3/3.1b1/hmmer-3.1b1-linux-intel-x86_64.tar.gz tar xvzf hmmer-3.1b1-cygwin.tar.gz cd hmmer-3.1b1-cygwin CFLAGS="-g -O1 -ftree-vrp -fexpensive-optimizations" ./configure make make check and following test fails: gdb src/impl_sse/optacc_utest Program received signal SIGSEGV, Segmentation fault. 0x0000000000406a2c in select_i (k=<optimized out>, i=0, gx=0x45ed60, gm=0x470420) at generic_optacc.c:293 293 path[0] = TSCDELTA(p7P_MI, k) * MMX(i-1,k); (gdb) bt #0 0x0000000000406a2c in select_i (k=<optimized out>, i=0, gx=0x45ed60, gm=0x470420) at generic_optacc.c:293 #1 p7_GOATrace (gm=0x470420, pp=pp@entry=0x466150, gx=gx@entry=0x45ed60, tr=tr@entry=0x46e4e0) at generic_optacc.c:220 #2 0x000000000040322f in utest_optacc (go=go@entry=0x44e010, r=r@entry=0x44e170, abc=abc@entry=0x44eb50, bg=bg@entry=0x44ed90, M=M@entry=45, L=L@entry=50, N=19) at ./optacc.c:659 #3 0x0000000000403613 in main (argc=<optimized out>, argv=<optimized out>) at ./optacc.c:801 I really tried to reduce test case, but unfortunately it's very hard to do it for the project. Please tell me if you are capable of reproducing the issue? Thanks, Martin