# D003 int_beyond_js_safe_range

URL: /docs/errors/D003
Markdown: /docs/errors/D003.md

> On the JS backend, an Int left the exactly representable range ±(2^53−1).

A runtime defect: the running program stops with it; no compile phase reports it, and `try` cannot catch it. `sakura explain D003` prints this explanation offline.

On the JS backend, an `Int` left the exactly representable range ±(2^53−1). v0 traps instead of
computing a silently wrong value (design §4.1).

Runtime defects come from running programs, so `compiler/tests/ui` has no fixture for them; the explanation above names the repair.