On armhf, make check in orc fails at random timing. (occasionally pass all tests)


[Environment]
- HW: Raspberry Pi3
- OS: Linux raspberrypi 4.9.79-v7+ #1091 SMP Tue Feb 6 13:18:45 GMT 2018 armv7l GNU/Linux (Raspbian Stretch)
- Compiler: Both gcc6.3.0(default) and gcc4.9.3-14 are tried; the results were same.
- Builder: meson and autoconf are tried; the results were same.
- Code Tag: orc-0.4.26 to orc-0.4.28 are tried; the results were same.


I have located the code of segfaults/bus error while running benchmorc.

The errors always happen at the following code point.  However, what test item fails depends on individual executions and looks like at random.

orcexecutor.c:
----------------------------------------
void
orc_executor_run (OrcExecutor *ex)
{
  void (*func) (OrcExecutor *);

  if (ex->program) {
    func = ex->program->code_exec;
  } else {
    OrcCode *code = (OrcCode *)ex->arrays[ORC_VAR_A2];
    func = code->exec;
  }
  if (func) {
    func (ex);  ****** <--- BAD THINGS WILL HAPPEN HERE *****
    /* ORC_ERROR("counters %d %d %d", ex->counter1, ex->counter2, ex->counter3); */
  } else {
    orc_executor_emulate (ex);
  }
}
----------------------------------------

Due to the failure mode, does the generated code have memory alignment issues?

I didn't observe the same issue on Raspbian Jessie.  So, the kernel and glibc behaviors might be related IMHO.