diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/corelib/tools/qhash.h | 21 |
1 files changed, 14 insertions, 7 deletions
diff --git a/src/corelib/tools/qhash.h b/src/corelib/tools/qhash.h index cee58a0f2f..67b3e026df 100644 --- a/src/corelib/tools/qhash.h +++ b/src/corelib/tools/qhash.h @@ -1848,21 +1848,28 @@ template <class Key, class T> size_t qHash(const QHash<Key, T> &key, size_t seed = 0) noexcept(noexcept(qHash(std::declval<Key&>())) && noexcept(qHash(std::declval<T&>()))) { - QtPrivate::QHashCombineCommutative hash; + size_t hash = 0; for (auto it = key.begin(), end = key.end(); it != end; ++it) { - const Key &k = it.key(); - const T &v = it.value(); - seed = hash(seed, std::pair<const Key&, const T&>(k, v)); + QtPrivate::QHashCombine combine; + size_t h = combine(seed, it.key()); + // use + to keep the result independent of the ordering of the keys + hash += combine(h, it.value()); } - return seed; + return hash; } template <class Key, class T> inline size_t qHash(const QMultiHash<Key, T> &key, size_t seed = 0) noexcept(noexcept(qHash(std::declval<Key&>())) && noexcept(qHash(std::declval<T&>()))) { - const QHash<Key, T> &key2 = key; - return qHash(key2, seed); + size_t hash = 0; + for (auto it = key.begin(), end = key.end(); it != end; ++it) { + QtPrivate::QHashCombine combine; + size_t h = combine(seed, it.key()); + // use + to keep the result independent of the ordering of the keys + hash += combine(h, it.value()); + } + return hash; } QT_END_NAMESPACE |