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q_uninitialized_relocate: use memcpy, not memmove

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The [first, first+n) and [out, out+n) ranges cannot possibly overlap, as
by definition the former contains live objects while the latter points
into uninitialized storage. So we can use memcpy here, and not memmove.

Change-Id: I4a1b39f73ffa67915c5252938554f45f4444293e
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
This commit is contained in:
Giuseppe D'Angelo 2023-02-17 15:36:51 +01:00
parent eb4641210c
commit 4dbd97c8f9
1 changed files with 4 additions and 4 deletions
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8
src/corelib/tools/qcontainertools_impl.h
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@ -72,10 +72,10 @@ template <typename T, typename N>
void q_uninitialized_relocate_n(T* first, N n, T* out)
{
if constexpr (QTypeInfo<T>::isRelocatable) {
if (n != N(0)) { // even if N == 0, out == nullptr or first == nullptr are UB for memmove()
std::memmove(static_cast<void*>(out),
static_cast<const void*>(first),
n * sizeof(T));
if (n != N(0)) { // even if N == 0, out == nullptr or first == nullptr are UB for memcpy()
std::memcpy(static_cast<void *>(out),
static_cast<const void *>(first),
n * sizeof(T));
}
} else {
q_uninitialized_move_if_noexcept_n(first, n, out);