Nested foralls with zippering and a throwing function call results in internal compiler error

[e-kayrakli]

module nestedForallThrows {

  config const flag = true;

  proc main() throws {

    forall i in zip(1..10, 1..10) {

      var x = foo();

      forall j in 1..10 {
        writeln(i,j);
      }

    }
  }

  proc foo() throws {

    if flag {
      throw new Error();
    }


    return 0;
  }
}

Results in internal error: did not find the insertion point [resolution/lowerIterators.cpp:2154]. This issue is there on main and also on Chapel 2.3.

Looking deeper, I see that we place iterator break blocks based on _freeIterator calls. I see in the AST that we don't even have a _freeIterator for the follower of the outer forall. That's why we can't find a place to insert the iterator break block.

Some more notes:

• change either loop to for and it works
• make the outer loop non-zip and it works
• it doesn't matter if the inner loop is zippered or not.