Problem with record coercion and inlining

[cristianoc]

In the following example name is 42 instead of "Name" because inlining presumably takes the value at face value and inlines the first element.

type a = {
  number: int,
  name: string,
}

type b = {
  name: string,
}

let a: a = {
  number: 42,
  name: "Name",
}

let name = (a :> b).name

[cristianoc]

The lambda output shows the issue:

(let (a/1007 = [0: 42 "Name"] name/1008 = (field:name/0 a/1007))
  (makeblock module/exports a/1007 name/1008))

Need to check if this prints the first or last version of lambda after optimisations.

[cristianoc]

That's the initial lambda before optimisation passes. So presumably this happens when translating to lambda.

[cristianoc]

Here's relevant code for field access. Labels in the typed tree are stored with their offset.
And the offset in this example is wrong.
In this specific case, the expression itself contains the record coercion, but in general it could have happened much earlier.

and type_label_access env srecord lid =
  let record = type_exp ~recarg:Allowed env srecord in
  let ty_exp = record.exp_type in
  let opath =
    try
      let (p0, p, _, _) = extract_concrete_record env ty_exp in
      Some(p0, p)
    with Not_found -> None
  in
  let labels = Typetexp.find_all_labels env lid.loc lid.txt in
  let label =
    wrap_disambiguate "This expression has" ty_exp
      (Label.disambiguate lid env opath) labels in
  (record, label, opath)