[Bug rtl-optimization/84345] New: [8 Regression] ICE: qsort checking failed (error: qsort comparator non-negative on sorted output: 1)

[asolokha at gmx dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84345

            Bug ID: 84345
           Summary: [8 Regression] ICE: qsort checking failed (error:
                    qsort comparator non-negative on sorted output: 1)
           Product: gcc
           Version: 8.0
            Status: UNCONFIRMED
          Keywords: ice-checking, ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: rtl-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: asolokha at gmx dot com
  Target Milestone: ---
            Target: x86_64-unknown-linux-gnu

gcc-8.0.0-alpha20180211 snapshot (r257571) ICEs when compiling the following
snippet w/ -O2 -fsched2-use-superblocks -ftree-parallelize-loops=2
-fno-sched-critical-path-heuristic -fno-tree-dce --param
tracer-min-branch-probability=49:

int zq, h9;

void
m0 (unsigned long int sc)
{
  zq = 0;

  if (sc == 0 && h9 == 0)
    for (sc = 0; sc < 200; ++sc)
      {
      }
}

% gcc-8.0.0-alpha20180211 -O2 -fsched2-use-superblocks
-ftree-parallelize-loops=2 -fno-sched-critical-path-heuristic -fno-tree-dce
--param tracer-min-branch-probability=49 -c nx05nihn.c
nx05nihn.c: In function 'm0':
nx05nihn.c:12:1: error: qsort comparator non-negative on sorted output: 1
 }
 ^
during RTL pass: sched2
nx05nihn.c:12:1: internal compiler error: qsort checking failed
0x7428bc qsort_chk_error
       
/var/tmp/portage/sys-devel/gcc-8.0.0_alpha20180211/work/gcc-8-20180211/gcc/vec.c:201
0x742923 qsort_chk(void*, unsigned long, unsigned long, int (*)(void const*,
void const*))
       
/var/tmp/portage/sys-devel/gcc-8.0.0_alpha20180211/work/gcc-8-20180211/gcc/vec.c:253
0x1479810 ready_sort_real
       
/var/tmp/portage/sys-devel/gcc-8.0.0_alpha20180211/work/gcc-8-20180211/gcc/haifa-sched.c:3086
0x14818e4 schedule_block(basic_block_def**, void*)
       
/var/tmp/portage/sys-devel/gcc-8.0.0_alpha20180211/work/gcc-8-20180211/gcc/haifa-sched.c:6674
0x150681b schedule_ebb(rtx_insn*, rtx_insn*, bool)
       
/var/tmp/portage/sys-devel/gcc-8.0.0_alpha20180211/work/gcc-8-20180211/gcc/sched-ebb.c:537
0x1506ee4 schedule_ebbs()
       
/var/tmp/portage/sys-devel/gcc-8.0.0_alpha20180211/work/gcc-8-20180211/gcc/sched-ebb.c:657
0xc4c294 rest_of_handle_sched2
       
/var/tmp/portage/sys-devel/gcc-8.0.0_alpha20180211/work/gcc-8-20180211/gcc/sched-rgn.c:3735
0xc4c294 execute
       
/var/tmp/portage/sys-devel/gcc-8.0.0_alpha20180211/work/gcc-8-20180211/gcc/sched-rgn.c:3873