[Bug tree-optimization/71908] New: ICE at -Os and above in both 32-bit and 64-bit modes on x86_64-linux-gnu (get_constraint_for_component_ref)

[chengniansun at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71908

            Bug ID: 71908
           Summary: ICE at -Os and above in both 32-bit and 64-bit modes
                    on x86_64-linux-gnu (get_constraint_for_component_ref)
           Product: gcc
           Version: 7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: chengniansun at gmail dot com
  Target Milestone: ---

$ gcc-trunk -v
Using built-in specs.
COLLECT_GCC=gcc-trunk
COLLECT_LTO_WRAPPER=/usr/local/gcc-trunk/libexec/gcc/x86_64-pc-linux-gnu/7.0.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: ../gcc-source-trunk/configure --enable-languages=c,c++,lto
--prefix=/usr/local/gcc-trunk --disable-bootstrap
Thread model: posix
gcc version 7.0.0 20160716 (experimental) [trunk revision 238415] (GCC) 
$ 
$ gcc-trunk -O3 small.c
small.c: In function ‘main’:
small.c:10:5: internal compiler error: in get_constraint_for_component_ref, at
tree-ssa-structalias.c:3217
 int main() {
     ^~~~
0xda58ec get_constraint_for_component_ref
        ../../gcc-source-trunk/gcc/tree-ssa-structalias.c:3217
0xda58ec get_constraint_for_1
        ../../gcc-source-trunk/gcc/tree-ssa-structalias.c:3485
0xda9500 find_func_aliases
        ../../gcc-source-trunk/gcc/tree-ssa-structalias.c:4779
0xdaf22e compute_points_to_sets
        ../../gcc-source-trunk/gcc/tree-ssa-structalias.c:7056
0xdaf22e compute_may_aliases()
        ../../gcc-source-trunk/gcc/tree-ssa-structalias.c:7414
0xae7924 execute_function_todo
        ../../gcc-source-trunk/gcc/passes.c:1936
0xae84eb execute_todo
        ../../gcc-source-trunk/gcc/passes.c:2016
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <http://gcc.gnu.org/bugs.html> for instructions.
$  cat small.c
struct S3 {
  int f3;
  int f5;
  char f6;
  int f7;
} b;
int a;
static struct S3 *c = &b;
int *d;
int main() {
  int i;
  for (;;) {
    a = 0;
    int **e = &d;
    i = 0;
    for (; i < 2; i++)
      d = &(*c).f5;
    *e = d;
    **e = 3;
  }
  return 0;
}

$