http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47060
Summary: [4.6 Regression] ICE: SIGSEGV in reduction_phi (tree-parloops.c:212) with -O -ffast-math -ftree-parallelize-loops=2 -fno-tree-dce Product: gcc Version: 4.6.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: tree-optimization AssignedTo: unassig...@gcc.gnu.org ReportedBy: zso...@seznam.cz Host: x86_64-pc-linux-gnu Target: x86_64-pc-linux-gnu Created attachment 22849 --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=22849 gcc.dg/graphite/id-14.c Compiler output: $ gcc -O -ffast-math -ftree-parallelize-loops=2 -fno-tree-dce id-14.c ==27629== Invalid read of size 4 ==27629== at 0x9348B3: reduction_phi (tree-parloops.c:212) ==27629== by 0x936C9F: parallelize_loops (tree-parloops.c:1912) ==27629== by 0x9B75B8: tree_parallelize_loops (tree-ssa-loop.c:589) ==27629== by 0x7F1745: execute_one_pass (passes.c:1553) ==27629== by 0x7F1A34: execute_pass_list (passes.c:1608) ==27629== by 0x7F1A46: execute_pass_list (passes.c:1609) ==27629== by 0x7F1A46: execute_pass_list (passes.c:1609) ==27629== by 0x931D25: tree_rest_of_compilation (tree-optimize.c:422) ==27629== by 0xAF7311: cgraph_expand_function (cgraphunit.c:1508) ==27629== by 0xAF99E9: cgraph_optimize (cgraphunit.c:1567) ==27629== by 0xAF9F69: cgraph_finalize_compilation_unit (cgraphunit.c:1031) ==27629== by 0x50983B: c_write_global_declarations (c-decl.c:9845) ==27629== by 0x8DB515: toplev_main (toplev.c:591) ==27629== by 0x6369BBC: (below main) (in /lib64/libc-2.11.2.so) ==27629== Address 0x4 is not stack'd, malloc'd or (recently) free'd ==27629== id-14.c: In function 'foo': id-14.c:7:1: internal compiler error: Segmentation fault Please submit a full bug report, with preprocessed source if appropriate. See <http://gcc.gnu.org/bugs.html> for instructions. Program received signal SIGSEGV, Segmentation fault. reduction_phi (reduction_list=0x17b9630, phi=0x0) at /mnt/svn/gcc-trunk/gcc/tree-parloops.c:212 212 tmpred.reduc_version = gimple_uid (phi); (gdb) bt #0 reduction_phi (reduction_list=0x17b9630, phi=0x0) at /mnt/svn/gcc-trunk/gcc/tree-parloops.c:212 #1 0x0000000000936ca0 in try_create_reduction_list () at /mnt/svn/gcc-trunk/gcc/tree-parloops.c:1912 #2 parallelize_loops () at /mnt/svn/gcc-trunk/gcc/tree-parloops.c:2035 #3 0x00000000009b75b9 in tree_parallelize_loops () at /mnt/svn/gcc-trunk/gcc/tree-ssa-loop.c:589 #4 tree_parallelize_loops () at /mnt/svn/gcc-trunk/gcc/tree-ssa-loop.c:584 #5 0x00000000007f1746 in execute_one_pass (pass=0x16375a0) at /mnt/svn/gcc-trunk/gcc/passes.c:1553 #6 0x00000000007f1a35 in execute_pass_list (pass=0x16375a0) at /mnt/svn/gcc-trunk/gcc/passes.c:1608 #7 0x00000000007f1a47 in execute_pass_list (pass=0x1637b40) at /mnt/svn/gcc-trunk/gcc/passes.c:1609 #8 0x00000000007f1a47 in execute_pass_list (pass=0x1636d60) at /mnt/svn/gcc-trunk/gcc/passes.c:1609 #9 0x0000000000931d26 in tree_rest_of_compilation (fndecl=0x7ffff5cc4f00) at /mnt/svn/gcc-trunk/gcc/tree-optimize.c:422 #10 0x0000000000af7312 in cgraph_expand_function (node=0x7ffff5ce4000) at /mnt/svn/gcc-trunk/gcc/cgraphunit.c:1508 #11 0x0000000000af99ea in cgraph_expand_all_functions () at /mnt/svn/gcc-trunk/gcc/cgraphunit.c:1567 #12 cgraph_optimize () at /mnt/svn/gcc-trunk/gcc/cgraphunit.c:1827 #13 0x0000000000af9f6a in cgraph_finalize_compilation_unit () at /mnt/svn/gcc-trunk/gcc/cgraphunit.c:1031 #14 0x000000000050983c in c_write_global_declarations () at /mnt/svn/gcc-trunk/gcc/c-decl.c:9845 #15 0x00000000008db516 in compile_file (argc=17, argv=0x7fffffffda88) at /mnt/svn/gcc-trunk/gcc/toplev.c:591 #16 do_compile (argc=17, argv=0x7fffffffda88) at /mnt/svn/gcc-trunk/gcc/toplev.c:1874 #17 toplev_main (argc=17, argv=0x7fffffffda88) at /mnt/svn/gcc-trunk/gcc/toplev.c:1937 #18 0x00007ffff6586bbd in __libc_start_main () from /lib/libc.so.6 #19 0x00000000004f0415 in _start () Tested revisions: r168214 - crash r165699 - OK 4.5 r168062 - OK