https://github.com/ClickHouse/ClickHouse/blob/9a48cf0da8badfc5f3da08611eb44961aa28e3f6/src/Functions/FunctionsHashing.h#L669-L671

There's a call to `blake3_free_char_pointer` that passes ownership of the pointer back to Rust (which then frees the memory), then there's a call to `std::string`'s constructor that accepts that now-freed pointer.
{
        
        if (const ColumnTuple * tuple = typeid_cast<const ColumnTuple *>(column))
        {
            const auto & tuple_columns = tuple->getColumns();
            const DataTypes & tuple_types = typeid_cast<const DataTypeTuple &>(*type).getElements();
            size_t tuple_size = tuple_columns.size();
            for (size_t i = 0; i < tuple_size; ++i)
                executeForArgument(tuple_types[i].get(), tuple_columns[i].get(), vec_to, is_first);
        }
        else if (const ColumnTuple * tuple_const = checkAndGetColumnConstData<ColumnTuple>(column))
        {
            const auto & tuple_columns = tuple_const->getColumns();
            const DataTypes & tuple_types = typeid_cast<const DataTypeTuple &>(*type).getElements();
            size_t tuple_size = tuple_columns.size();
            for (size_t i = 0; i < tuple_size; ++i)
            {
                auto tmp = ColumnConst::create(tuple_columns[i], column->size());
                executeForArgument(tuple_types[i].get(), tmp.get(), vec_to, is_first);
            }
        }
        else if (const auto * map = checkAndGetColumn<ColumnMap>(column))
        {
            const auto & type_map = assert_cast<const DataTypeMap &>(*type);
            executeForArgument(type_map.getNestedType().get(), map->getNestedColumnPtr().get(), vec_to, is_first);
        }
        else if (const auto * const_map = checkAndGetColumnConstData<ColumnMap>(column))
        {
            const auto & type_map = assert_cast<const DataTypeMap &>(*type);