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.
Two lowering sites materialized a local array as a whole LLVM value;
the legalizer scalarizes each such op into one SelectionDAG node per
element, and at ~64K elements the DAG combiner segfaults
(DAGCombiner::visitMERGE_VALUES → ReplaceAllUsesWith).
- lowerVarDecl: an array-typed `---` initializer emits NO store — the
slot stays uninitialized instead of receiving a whole-array undef
store. The tuple zero-init carve-out stays; non-array `---` keeps
the undef store. The interp is unchanged either way (slots start
.undef).
- lowerIndexExpr: element reads on an array with addressable storage
GEP the storage and load one element — the general-expression
sibling of 0110's lowerFor fix — without value-lowering the object
(a dead whole-array load would still reach the DAG). Storage-less
arrays keep the index_get fallback.
Sibling shape filed as 0125: any_to_string's per-array-type arms still
pass the array by value, so a 64K+ array type + any {} print crashes.
Regression: examples/0055-basic-large-stack-array.sx (sx build
segfaulted pre-fix). 22 .ir snapshots re-pinned: removed undef stores
and ig.tmp spills, in-place gep+load (instruction-shape-only churn,
reviewed).
