Files
sx/examples/0167-types-ptr-to-aggregate-field-store.sx
agra d8076b9333 lang: rename signed integer types sN -> iN
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.
2026-06-12 09:31:53 +03:00

43 lines
1.8 KiB
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// Storing a struct field whose own type is a pointer to a two-pointer struct
// (`*Pair` — the shape `coerceArg` would closure-auto-promote into `{ptr,null}`)
// must store an 8-byte pointer, never a 16-byte struct that overruns the slot
// and clobbers the neighbouring field. The shared field-lvalue resolver types
// the GEP as `*field_ty`, so `emitStore` unwraps exactly one pointer level to
// the field's own type (`*Pair`, an opaque pointer) instead of the pointee
// aggregate (`Pair`).
//
// Regression (issue 0094, attempt-3 consolidation): the shared `fieldLvaluePtr`
// resolver used to type struct/tuple GEPs with the bare field value type, so a
// `*Pair` field stored via the multi-assign / address-of paths promoted the
// pointer to a 16-byte struct and clobbered the next field (`sentinel` read 0).
// The single-assign path already used the `*field_ty` convention; folding all
// three lvalue sites onto the one resolver applies it uniformly.
#import "modules/std.sx";
Pair :: struct { a: *i64; b: *i64; }
Holder :: struct { pr: *Pair; sentinel: i64; }
main :: () {
x : i64 = 7;
y : i64 = 9;
pair : Pair = .{ a = @x, b = @y };
other : Pair = .{ a = @y, b = @x };
h : Holder = .{ pr = @pair, sentinel = 99 };
// single-assign: store a *Pair into h.pr; sentinel must stay 99.
h.pr = @other;
print("single: a={} b={} sentinel={}\n", h.pr.a.*, h.pr.b.*, h.sentinel);
// multi-assign: store into h.pr alongside a plain local; sentinel untouched.
dummy : i64 = 0;
h.pr, dummy = @pair, 1;
print("multi: a={} b={} sentinel={}\n", h.pr.a.*, h.pr.b.*, h.sentinel);
// address-of the *Pair field, store through it; sentinel untouched.
ppr := @h.pr;
ppr.* = @other;
print("addr: a={} b={} sentinel={}\n", h.pr.a.*, h.pr.b.*, h.sentinel);
}