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Fix flat_hash_map when used across library boundaries. #1931

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Merged
borisbat merged 1 commit into from
Nov 13, 2025
Merged

Fix flat_hash_map when used across library boundaries. #1931

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24 changes: 12 additions & 12 deletions include/ska/flat_hash_map.hpp
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Original file line number Diff line number Diff line change
Expand Up @@ -164,12 +164,6 @@ struct sherwood_v3_entry
~sherwood_v3_entry()
{
}
static sherwood_v3_entry * empty_default_table()
{
static sherwood_v3_entry result[min_lookups] = { {}, {}, {}, {special_end_value} };
return result;
}

bool has_value() const
{
return distance_from_desired >= 0;
Expand Down Expand Up @@ -755,13 +749,22 @@ class sherwood_v3_table : private EntryAlloc, private Hasher, private Equal
}

private:
EntryPointer entries = Entry::empty_default_table();
EntryPointer entries = empty_default_table();
size_t num_slots_minus_one = 0;
typename HashPolicySelector<ArgumentHash>::type hash_policy;
int8_t max_lookups = detailv3::min_lookups - 1;
float _max_load_factor = 0.5f;
size_t num_elements = 0;

EntryPointer empty_default_table()
{
EntryPointer result = AllocatorTraits::allocate(*this, detailv3::min_lookups);
EntryPointer special_end_item = result + static_cast<ptrdiff_t>(detailv3::min_lookups - 1);
for (EntryPointer it = result; it != special_end_item; ++it)
it->distance_from_desired = -1;
special_end_item->distance_from_desired = Entry::special_end_value;
return result;
}
static int8_t compute_max_lookups(size_t num_buckets)
{
int8_t desired = detailv3::log2(num_buckets);
Expand Down Expand Up @@ -841,16 +844,13 @@ class sherwood_v3_table : private EntryAlloc, private Hasher, private Equal

void deallocate_data(EntryPointer begin, size_t num_slots_minus_one_, int8_t max_lookups_)
{
if (begin != Entry::empty_default_table())
{
AllocatorTraits::deallocate(*this, begin, num_slots_minus_one_ + max_lookups_ + 1);
}
AllocatorTraits::deallocate(*this, begin, num_slots_minus_one_ + max_lookups_ + 1);
}

void reset_to_empty_state()
{
deallocate_data(entries, num_slots_minus_one, max_lookups);
entries = Entry::empty_default_table();
entries = empty_default_table();
num_slots_minus_one = 0;
hash_policy.reset();
max_lookups = detailv3::min_lookups - 1;
Expand Down