# V3 step 8.3 — `QbeGen` compiles clean; empty statements; 1-char strings (105/105)

Both hand-written compiler modules now compile clean under V3.

## What landed

1. **Within-module forward procedure calls (gm2-compatible sources).**
   `QbeGen.mod` calls 10 internal helpers before their definitions.
   gm2's `FORWARD` is unusable (its whole-program pass errors with
   `too many errors in pass 3` — reproduced with a minimal module),
   and reordering cascades through `NewTemp`/`Op3L`/`Revive`/
   `HeapSize`/`InitStack`. Fix: declare the 10 helpers in
   `QbeGen.def` (its role is already "everything the generated
   parser needs"), so they are visible throughout the
   implementation. `ArrData`/`HeapSize` signatures use `INTEGER` in
   both def and impl.

2. **Single-character string literals for `ARRAY OF CHAR`.** `"("`,
   `"0"`, `"$"` etc. were typed `CHAR`, so `W("(")` reported
   "invalid call". New `QbeGen.DeclCharStr` synthesizes the
   equivalent 1-char string descriptor; `ActParam` uses it when the
   formal is an array of `CHAR` and the actual is an immediate
   `CHAR`. This cleared all 85 remaining `QbeGen` errors.

3. **Empty statements.** `StatSeq = Statement { ";" [ Statement ] }`
   accepts `;;`, lone `;` and trailing `;` — required because
   Coco/R emits `;;` in the generated `M2P.mod`. New test
   `tests/t_emptystat.mod` (42). Also removed a stray `END;;` in
   `QbeGen.mod`.

## Result

- `SymTab.def/.mod`: clean (step 8.2).
- `QbeGen.def/.mod`: **clean** (this step).
- Suite **105/105**, build warning-free.

## Remaining self-hosting gaps (measured)

Coco/R-generated sources `src/M2S.mod` (30 errors), `src/M2P.mod`,
`src/M2.mod`:

- **Procedure types** are unsupported: `GetCH = PROCEDURE (INT32):
  CHAR;` and procedure variables (`CurrentCh: GetCH;`), and the
  `Error: PROCEDURE (...)` callback in `M2S.def`. This is the main
  `M2S` blocker (`invalid Type`, then cascade). Likely step 9.
- **`INT32` (a `FileIO.INT32` alias) is seen as "not a type name"**
  in `M2S.mod` var/param types — need to confirm once procedure
  types parse.
- **Host `FileIO` open-file cap:** `MaxFiles = BitSetSize` (16)
  blocks compiling all ~16 compiler modules in one driver session
  (`Too many files`). Raise it, or use the self-hosted `FileIO`
  (stage-2 syslib) whose limit can be larger.

## Files

`compiler/src/{QbeGen.def,QbeGen.mod,M2.atg}`,
`compiler/tests/t_emptystat.mod`, `compiler/run_tests.sh`.