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"path": "/t/instant-past-value-constant/24297#post_2",
"publishedAt": "2026-05-12T19:02:52.000Z",
"site": "https://internals.rust-lang.org",
"textContent": "One potential problem I can foresee is that because this is loosely defined (there are many possible values that all work), it might cause compatibility problems going forwards (where we might have a reason to change it from one value to a different value, but that might break existing code that is, e.g., using it as a sentinel), or where it's used as a sentinel on one platform and then an attempt is made to read it from a different platform where the value is different (although `Instant` is already platform-specific enough that such code would already likely be broken, so maybe that isn't an issue).\n\nI assume that the reason why you want this rather than just using `Instant::now()` is so that it can be a compile-time constant? (Guaranteeing that an `Instant` is _strictly_ in the past is difficult due to the possibility of a Rust program running during very early boot, before the timestamp has had a chance to change from its minimum value.)",
"title": "`Instant::PAST_VALUE` constant?"
}