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rust-lang · Sep 18, 2017 · 10384ab · 10384ab
1 parent 4de0cf1
commit 10384ab
Showing 1 changed file with 3 additions and 0 deletions.
diff --git a/src/liballoc/vec.rs b/src/liballoc/vec.rs
@@ -2694,6 +2694,9 @@ impl<'a, T, F> Iterator for DrainFilter<'a, T, F>
                     let del = self.del;
                     let src: *const T = &v[i];
                     let dst: *mut T = &mut v[i - del];
+                    // This is safe because self.vec has length 0
+                    // thus its elements will not have Drop::drop
+                    // called on them in the event of a panic.
                     ptr::copy_nonoverlapping(src, dst, 1);
                 }
             }