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diff --git a/src/tools/clippy/src/docs/manual_instant_elapsed.txt b/src/tools/clippy/src/docs/manual_instant_elapsed.txt
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+### What it does
+Lints subtraction between `Instant::now()` and another `Instant`.
+
+### Why is this bad?
+It is easy to accidentally write `prev_instant - Instant::now()`, which will always be 0ns
+as `Instant` subtraction saturates.
+
+`prev_instant.elapsed()` also more clearly signals intention.
+
+### Example
+```
+use std::time::Instant;
+let prev_instant = Instant::now();
+let duration = Instant::now() - prev_instant;
+```
+Use instead:
+```
+use std::time::Instant;
+let prev_instant = Instant::now();
+let duration = prev_instant.elapsed();
+```
+\ No newline at end of file