Surface rename of the signed integer family: s1..s64 become i1..i64
(u1..u64, usize, isize unchanged). 'string' keeps the s-prefix arm in
name classification; width parsing moves to the i-prefix arm next to
isize.
Internal TypeId tags follow the surface (.s8/.s16/.s32/.s64 ->
.i8/.i16/.i32/.i64), as do mono-key mangle fragments (ptr_i64,
tu_i64_bool) and all display/diagnostic formatting (i{d}).
Migrated in the same sweep: stdlib + examples + issue repros + FFI C
companions (shared symbol names like ffi_id_i64), expected
stdout/stderr/ir snapshots, specs.md, readme.md, CLAUDE.md/AGENTS.md,
implementation_plan.md, docs/, issue writeups. Vendored stb_image and
historical flow state left untouched.
zig build test: 426/426; examples suite: 595/595.
A struct constant whose every field serializes — literals, enum tags,
nested aggregates, and (new) const EXPRESSIONS over named consts /
const-aggregate leaves ('r = K + 1', 'g = LIT.r', 'b = A[1]') — becomes
an immutable global: one storage, reads load/GEP it, '@LIT' is
addressable, dead-global elimination drops unused ones. constExprValue
gained a fold-through tail (evalConstIntExpr/evalConstFloatExpr,
source-aware), which also enables const-expression ELEMENTS in array
consts.
A const with a NON-serializable field (a call, a runtime read) keeps
inline re-lowering, and that per-use evaluation is now the documented
contract for the class (pinned: 'CALL.r' reads 1 then 2, side effects
run per use; '#run' is the evaluate-once tool).
Examples: 0180 (migrated shapes + @ptr + copy independence),
0181 (the inline-fallback contract). m3te (23/23) + game rebuilt green.
