# Session save — 2026-09-30: VAL conversions + long→int narrowing

Suite **148/148**; self-hosting fixpoint **OK**
(`bootstrap/fixpoint.sh`, image **2,320,770 bytes**). `master`, tree
clean except the user's uncommitted `compiler/toto.mod`.

A short session: the remaining numeric conversion gap.

## Step, tag and commit

| Step | Tag | Commit | What |
| --- | --- | --- | --- |
| VAL conversions | `v3-val-conversions` | `1c774a7` | INTEGER/LONGINT/REAL conversions + long→int narrowing |

## What

`VAL` previously accepted only same-class operands and emitted **no**
conversion code.  It now covers:

| From → To | Codegen |
| --- | --- |
| `INTEGER` → `LONGINT` | `extsw` |
| `LONGINT` → `INTEGER` | `copy w` (low 32 bits) |
| `INTEGER` → `REAL` | `swtof` |
| `LONGINT` → `REAL` | `sltof` |
| `REAL` → `INTEGER` / `LONGINT` | `dtosi` (truncate toward zero) |

Ordinal↔ordinal, pointer↔pointer and REAL↔REAL were already allowed.
New `QbeGen` helpers: `NarrowLong`, `ConvRI`, `ConvRL`, `ConvLR`
(alongside `WidenLong`/`ConvIR`).

## Payoff

`Conversions` is simplified: `StrToInt`/`StrToCard` accumulate in a
`LONGINT` and range-check, then narrow with `VAL(INTEGER, v)` /
`VAL(CARDINAL, v)`; the old "detect overflow before the 32-bit wrap"
hand-guard is gone.

## Tests (148)

New: `t_valconv` (15) — int→long→int round-trip, int→real, real→int
truncation, long→real.  `ConvProg`/`ConvResultsProg` still pass.

Docs: `docs/summary_val-conversions.md`.

## Resume

```sh
cd .../m2compiler-V3
./bootstrap/fixpoint.sh                       # FIXPOINT OK
cd compiler && ./build.sh && ./run_tests.sh   # 148/148
```

## Remaining polish

- Multiple parents for `CLASS` (deliberate exclusion).
- More stdlib: `SysClock`, richer `Strings` (`Insert`/`Replace`/
  `Capitalize`), more `Math`.
- Deeper variant-record / `IOChan` support.