Local variables through let expressions are broken

[TobiasWrigstad]

I am compiling this code:

let i = this.start in 
  while i < this.stop 
    {
      if this.prime_array.is_not_flagged(i) then this.pass_on(i) else ();
      i = i + 1
    };

in which I expect that i is a local variable, whose initial value is that of this.start, and for each turn in the loop, i is incremented by 1.

However, the code that I see generated is the following:

void* _tmp9;
while (({;
         ;
         int _tmp3 = ((*this).start < (*this).stop);;; _tmp3;}))
{
  void* _tmp4_ite;
  if (({int _tmp6 = PrimeArray_is_not_flagged((*this).prime_array, ({ (*this).start;})); _tmp6;}))
  {
    Filter_pass_on(this, ({ (*this).start;}));;
    _tmp4_ite = UNIT;;;
  }
  else
  {
    UNIT;;
    _tmp4_ite = UNIT;;;
  };;
  ;
  int64_t _tmp7 = 1;;
  int64_t _tmp8 = ((*this).start + _tmp7);;;;
  ;
  (*this).start = _tmp8;;;;;
  _tmp9 = UNIT;;;
};;;

which replaces i with this.start and modifies this.start in each increment! This clearly cannot be right, right?

[supercooldave]

This is not right.

Sent from my iPhone

[TobiasWrigstad]

Here is a test that reproduces the bug (I will commit it to the repo)

class Main
  value : int
  def main() : void {
    this.value = 1024;
    let x = this.value in {
      x = x + 1;
      if x == 1024 then
        print "Failue when reading x -- expected 1024, got something else"
      else
        print "Test 1 OK";
      if x == this.value then
        print "Failue when comparing x and this.value -- they are the same but should not be"
      else
        print "Test 2 OK";
    }
  }

When run, this prints out

Test 1 OK
Failue when comparing x and this.value -- they are the same but should not be

[supercooldave]

Shouldn't it read "expected 1025"?

[kaeluka]

Found the bug, fix should be easy.

[TobiasWrigstad]

@supercooldave The key thing is not the value, but that the value of the field and variable are different. If they are both at 1025, bug still persists.

[supercooldave]

My comment was on the text of the test case.

[TobiasWrigstad]

@supercooldave Right! My bad. I'll fix.

EDIT Fixed. It now reads "Got 1024, expected something else" :)

[kaeluka]

0e31620 The test passes now.