// rt — runtime primitives exposed to ww programs.
// Mirrors Hare's rt:: module placement (ref/hare/rt/).

package rt;

// malloc — mmap-backed page allocator. Untyped: `malloc(n)` returns a
// `*void`; callers cast to the target type. Diverges from Hare: Hare
// exposes `alloc` / `free` as typed language builtins that the
// compiler lowers to rt::malloc/rt::free; ww has no such builtins,
// so the rt-symbol surface is exposed directly. Stdlib callers that
// need a typed allocation pattern wrap this with a cast plus a stored
// capacity (see [[strings.dup]], [[memio.dynamic]]).
//
// OOM: rt_malloc is a bare mmap(MAP_ANON|MAP_PRIVATE) wrapper with no
// error path. The raw Linux mmap syscall returns a negative errno cast
// to `*void` on failure (e.g. `(void*)-12` for ENOMEM); the
// `MAP_FAILED` (`(void*)-1`) value is a libc-wrapper convention that
// rt_malloc doesn't apply. Neither `== nil` nor `== (void*)-1` catches
// it; any deref of such a return faults. Today the stdlib does not
// check; OOM faults on first dereference. A typed fallible variant is
// a future task (task #39). ref/hare/rt/malloc.ha:27.
@symbol("rt_malloc") export fn malloc(n: u64) *void;