// Phase 1.1 — the compiler-internal heap-copy that backs `xx <rvalue>`
// protocol erasure must dispatch through `context.allocator`, not call
// libc malloc directly. So when a `push Context.{ allocator = tracer }`
// block is active, a `xx StructLiteral.{}` inside it MUST be allocated
// by the tracker.
//
// Note: `xx` only heap-copies for RVALUES (struct literals, call results).
// `xx <lvalue>` (an identifier, field access, index, or deref) borrows
// the operand's storage, so it never allocates and never reaches this
// path. See specs.md §3 — Protocol value ownership and lifetime.
#import "modules/std.sx";
#import "modules/std/mem.sx"; // `Allocator` is non-transitive: name it, import it.

Tracer :: struct {
    count: i64;

    init :: () -> *Tracer {
        t : *Tracer = xx libc_malloc(size_of(Tracer));
        t.count = 0;
        t
    }
}

impl Allocator for Tracer {
    alloc_bytes :: (self: *Tracer, size: i64) -> *void {
        self.count += 1;
        return libc_malloc(size);
    }
    dealloc_bytes :: (self: *Tracer, ptr: *void) {
        libc_free(ptr);
    }
}

main :: () -> i32 {
    tracer := Tracer.init();
    push Context.{ allocator = xx tracer, data = null } {
        // Struct-literal operand: rvalue → heap-copy through context.allocator.
        // The erased type must actually `impl Allocator` (erasure is
        // impl-driven, issue 0176), so use a fresh `Tracer.{}` rvalue — the
        // copy is what we want routed through the active allocator.
        ignore : Allocator = xx Tracer.{ count = 0 };
        _ = ignore;
    }
    print("Tracer.count = {}\n", tracer.count);
    0
}