| @@ -1379,9 +1379,6 @@ impl<T, A: Allocator> Vec<T, A> { |
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| 1379 |
1379 |
} |
| 1380 |
1380 |
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| 1381 |
1381 |
let len = self.len(); |
| 1382 |
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-if index > len { |
| 1383 |
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-assert_failed(index, len); |
| 1384 |
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-} |
| 1385 |
1382 |
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| 1386 |
1383 |
// space for the new element |
| 1387 |
1384 |
if len == self.buf.capacity() { |
| @@ -1393,9 +1390,15 @@ impl<T, A: Allocator> Vec<T, A> { |
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| 1393 |
1390 |
// The spot to put the new value |
| 1394 |
1391 |
{ |
| 1395 |
1392 |
let p = self.as_mut_ptr().add(index); |
| 1396 |
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-// Shift everything over to make space. (Duplicating the |
| 1397 |
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-// `index`th element into two consecutive places.) |
| 1398 |
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- ptr::copy(p, p.offset(1), len - index); |
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1393 |
+if index < len { |
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1394 |
+// Shift everything over to make space. (Duplicating the |
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1395 |
+// `index`th element into two consecutive places.) |
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1396 |
+ ptr::copy(p, p.offset(1), len - index); |
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1397 |
+} else if index == len { |
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1398 |
+// No elements need shifting. |
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1399 |
+} else { |
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1400 |
+assert_failed(index, len); |
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1401 |
+} |
| 1399 |
1402 |
// Write it in, overwriting the first copy of the `index`th |
| 1400 |
1403 |
// element. |
| 1401 |
1404 |
ptr::write(p, element); |