[Bug tree-optimization/82441] New: ICE on valid code at -O3: qsort checking failed

[su at cs dot ucdavis.edu]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82441

            Bug ID: 82441
           Summary: ICE on valid code at -O3: qsort checking failed
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: su at cs dot ucdavis.edu
  Target Milestone: ---

$ gcctk -v
Using built-in specs.
COLLECT_GCC=gcctk
COLLECT_LTO_WRAPPER=/home/su/software/tmp/gcc/gcc-trunk/libexec/gcc/x86_64-pc-linux-gnu/8.0.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: ../gcc-source-trunk/configure --enable-languages=c,c++,lto
--prefix=/home/su/software/tmp/gcc/gcc-trunk --disable-bootstrap
Thread model: posix
gcc version 8.0.0 20171005 (experimental) [trunk revision 253450] (GCC)
$
$ gcctk -O2 small.c
$ gcc-7.2.0 -O3 small.c
$
$ gcctk -O3 small.c
small.c: In function ‘fn1’:
small.c:8:6: error: qsort comparator non-negative on sorted output: 1
 void fn1 ()
      ^~~
during GIMPLE pass: slp
small.c:8:6: internal compiler error: qsort checking failed
0x66ef85 qsort_chk_error
        ../../gcc-source-trunk/gcc/vec.c:222
0x14dfc15 qsort_chk(void*, unsigned long, unsigned long, int (*)(void const*,
void const*))
        ../../gcc-source-trunk/gcc/vec.c:274
0x14c1953 vec<data_reference*, va_heap, vl_embed>::qsort(int (*)(void const*,
void const*))
        ../../gcc-source-trunk/gcc/vec.h:973
0x14c1953 vec<data_reference*, va_heap, vl_ptr>::qsort(int (*)(void const*,
void const*))
        ../../gcc-source-trunk/gcc/vec.h:1735
0x14c1953 vect_analyze_data_ref_accesses(vec_info*)
        ../../gcc-source-trunk/gcc/tree-vect-data-refs.c:2802
0xf15f66 vect_slp_analyze_bb_1
        ../../gcc-source-trunk/gcc/tree-vect-slp.c:2869
0xf15f66 vect_slp_bb(basic_block_def*)
        ../../gcc-source-trunk/gcc/tree-vect-slp.c:3034
0xf17865 execute
        ../../gcc-source-trunk/gcc/tree-vectorizer.c:998
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.
$


----------------------------------


struct A
{ 
  short b;
} c[1][4][9];

unsigned d, e, f, g;

void fn1 ()
{ 
  for (; e; e++)
    ;
  if (f)
    for (d = 0; d < 4; d++)
      for (g = 0; g < 9; g++)
        { 
          struct A i = { 1 };
          c[f][d][g] = i;
        }
}

int main ()
{ 
  fn1 ();
  return 0;
}