Files
sx/examples/1136-diagnostics-array-dim-nonconst-direct-no-crash.sx
agra a821323c3c fix(ir): converge the comptime-int count surface (0083)
Three adjacent cells of the shared count surface still diverged from the
rest; all now route through the same leaf+fold+narrow+diagnose path.

1. Aliased integer constraint bypassed the value-param range gate — only
   builtin constraint names matched intTypeRange, so Box(5_000_000_000)
   with `$K: Count` (Count :: u32) compiled and bound a truncated value.
   resolveValueParamArg (shared by both the struct AND type-fn binder) now
   resolves the constraint to its underlying builtin via
   canonicalIntConstraintName (Count -> u32, Small -> s8) before
   range-checking, so an aliased integer constraint behaves exactly like
   the builtin it names.

2. A named const with an expression RHS (M :: 2; N :: M + 1) did not fold
   as a count — moduleConstInt read only a literal RHS node. It now folds
   every const's RHS through the shared evalConstIntExpr, cycle-guarded
   (mutual / self cycles fold to null, not a stack overflow), and pass-0
   pre-registers expression-RHS consts. N :: M + 1 == 3 at every consumer:
   dim (direct + alias), Vector lane, value-param (struct + type-fn),
   inline for.

3. Stateful resolveArrayLen still fabricated length 0 after a failed fold;
   it now returns null -> the .unresolved sentinel (no fabrication). The
   binding's lowering never reaches sizeOf (alloca defers it; hasErrors
   aborts first) and a field access on an already-diagnosed .unresolved
   value is poison-suppressed (emitFieldError), so a failed-fold dim emits
   ONE clean diagnostic with no panic.

Regressions: examples/0146 (full positive matrix — every consumer x leaf
form), 1135 (aliased u32 + s8 overflow), 1136 (direct non-const dim halts
cleanly). The cascade cleanup also tightened 1502/1503 to one diagnostic.
Unit test added for moduleConstInt expression-folding + cycle detection.
2026-06-04 14:09:46 +03:00

23 lines
1.0 KiB
Plaintext

// A DIRECT array dimension that is genuinely not a compile-time integer (a
// runtime call) is a hard error — ONE clean diagnostic + non-zero exit. Crucially
// it must NOT fabricate a length and must NOT crash later in lowering: the bad
// var is used downstream (element store + read, `.len`), and lowering has to bail
// gracefully on the `.unresolved` type rather than `@panic` in `sizeOf` or pile
// on cascade errors.
//
// Regression (issue 0083): the stateful `resolveArrayLen` emitted the diagnostic
// then `return 0` — fabricating a 0-length array (0-byte alloca, OOB access) to
// dodge the `sizeOf` panic. It now returns null → the `.unresolved` sentinel; the
// binding's lowering bails on it (a field access on an already-diagnosed
// `.unresolved` value stays silent), so the single real diagnostic aborts the
// build with no fabrication and no panic.
#import "modules/std.sx";
get :: () -> s64 { return 5; }
main :: () {
a : [get()]s64 = ---;
a[0] = 7;
print("unreachable: {} {}\n", a.len, a[0]);
}