Get rid of mem::uninitialized() #3
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RalfJung
reviewed
Oct 25, 2020
| ptr::copy_nonoverlapping(value, vec.get_unchecked_mut(old_len), 1); | ||
| vec.set_len(old_len + 1); |
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Yes that is much better than mucking about with uninitialized memory. :)
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Replace uses of mem::uninitialized() with v.reserve() + v.set_len().
mem::uninitialized() has tendency for causing UB, and recent vesions of rustc compile it to panic with many types.
The recommendation is to replace uses of mem::uninitialized() with mem::MaybeUninit. However, in this case,
since mem::uninitialized() is just used to allocate memory, it is much more straightforward to first use .reserve()
to reserve memory, then copy to vector, and then .set_len() to add the newly copied elements into vector.
This also avoids any MSRV bump, as .reseve() and .set_len() are both since 1.0 (unlike MaybeUninit, which is
since 1.36).
Closes #2