iterator resulting from find() cannot be compared to cend()

[instibrad]

Test code:
`TEST(sparsehash, densehashmap) {
google::dense_hash_map<uint32_t, std::string> map;

map.set_empty_key(0);
map.set_deleted_key(std::numeric_limits<uint32_t>::max());

EXPECT_TRUE(map.find(1) == map.cend());

}
`

results in compile error:
In file included from /home/bgreen/dev/git/edge-suite/ext/googletest/include/gtest/gtest.h:58, from /home/bgreen/dev/git/edge-suite/baselib/test/unit/ext/sparsehash-unit.cpp:11: /home/bgreen/dev/git/edge-suite/baselib/test/unit/ext/sparsehash-unit.cpp: In member function ?virtual void sparsehash_densehashmap_Test::TestBody()?: /home/bgreen/dev/git/edge-suite/baselib/test/unit/ext/sparsehash-unit.cpp:22:29: error: no match for ?operator==? (operand types are ?google::dense_hash_map<unsigned int, std::basic_string<char> >::iterator? {aka ?google::dense_hashtable_iterator<std::pair<const unsigned int, std::basic_string<char> >, unsigned int, std::hash<unsigned int>, google::dense_hash_map<unsigned int, std::basic_string<char> >::SelectKey, google::dense_hash_map<unsigned int, std::basic_string<char> >::SetKey, std::equal_to<unsigned int>, google::libc_allocator_with_realloc<std::pair<const unsigned int, std::basic_string<char> > > >?} and ?google::dense_hash_map<unsigned int, std::basic_string<char> >::const_iterator? {aka ?google::dense_hashtable_const_iterator<std::pair<const unsigned int, std::basic_string<char> >, unsigned int, std::hash<unsigned int>, google::dense_hash_map<unsigned int, std::basic_string<char> >::SelectKey, google::dense_hash_map<unsigned int, std::basic_string<char> >::SetKey, std::equal_to<unsigned int>, google::libc_allocator_with_realloc<std::pair<const unsigned int, std::basic_string<char> > > >?}) EXPECT_TRUE(map.find(1) == map.cend()); ~~~~~~~~~~~~^~~~~~~~~~~~~ /home/bgreen/dev/git/edge-suite/ext/googletest/include/gtest/internal/gtest-internal.h:1189:34: note: in definition of macro ?GTEST_TEST_BOOLEAN_? ::testing::AssertionResult(expression)) \ ^~~~~~~~~~ /home/bgreen/dev/git/edge-suite/baselib/test/unit/ext/sparsehash-unit.cpp:22:5: note: in expansion of macro ?EXPECT_TRUE? EXPECT_TRUE(map.find(1) == map.cend()); ^~~~~~~~~~~ In file included from /home/bgreen/dev/git/edge-suite/ext/sparsehash/include/sparsehash/dense_hash_map:105, from /home/bgreen/dev/git/edge-suite/baselib/test/unit/ext/sparsehash-unit.cpp:13: /home/bgreen/dev/git/edge-suite/ext/sparsehash/include/sparsehash/internal/densehashtable.h:192:8: note: candidate: ?bool google::dense_hashtable_iterator<V, K, HF, ExK, SetK, EqK, A>::operator==(const iterator&) const [with V = std::pair<const unsigned int, std::basic_string<char> >; K = unsigned int; HF = std::hash<unsigned int>; ExK = google::dense_hash_map<unsigned int, std::basic_string<char> >::SelectKey; SetK = google::dense_hash_map<unsigned int, std::basic_string<char> >::SetKey; EqK = std::equal_to<unsigned int>; A = google::libc_allocator_with_realloc<std::pair<const unsigned int, std::basic_string<char> > >; google::dense_hashtable_iterator<V, K, HF, ExK, SetK, EqK, A>::iterator = google::dense_hashtable_iterator<std::pair<const unsigned int, std::basic_string<char> >, unsigned int, std::hash<unsigned int>, google::dense_hash_map<unsigned int, std::basic_string<char> >::SelectKey, google::dense_hash_map<unsigned int, std::basic_string<char> >::SetKey, std::equal_to<unsigned int>, google::libc_allocator_with_realloc<std::pair<const unsigned int, std::basic_string<char> > > >]? bool operator==(const iterator& it) const { return pos == it.pos; } ^~~~~~~~ /home/bgreen/dev/git/edge-suite/ext/sparsehash/include/sparsehash/internal/densehashtable.h:192:8: note: no known conversion for argument 1 from ?google::dense_hash_map<unsigned int, std::basic_string<char> >::const_iterator? {aka ?google::dense_hashtable_const_iterator<std::pair<const unsigned int, std::basic_string<char> >, unsigned int, std::hash<unsigned int>, google::dense_hash_map<unsigned int, std::basic_string<char> >::SelectKey, google::dense_hash_map<unsigned int, std::basic_string<char> >::SetKey, std::equal_to<unsigned int>, google::libc_allocator_with_realloc<std::pair<const unsigned int, std::basic_string<char> > > >?} to ?const iterator&? {aka ?const google::dense_hashtable_iterator<std::pair<const unsigned int, std::basic_string<char> >, unsigned int, std::hash<unsigned int>, google::dense_hash_map<unsigned int, std::basic_string<char> >::SelectKey, google::dense_hash_map<unsigned int, std::basic_string<char> >::SetKey, std::equal_to<unsigned int>, google::libc_allocator_with_realloc<std::pair<const unsigned int, std::basic_string<char> > > >&?} In file included from /home/bgreen/dev/git/edge-suite/ext/sparsehash/include/sparsehash/internal/densehashtable.h:102, from /home/bgreen/dev/git/edge-suite/ext/sparsehash/include/sparsehash/dense_hash_map:105, from /home/bgreen/dev/git/edge-suite/baselib/test/unit/ext/sparsehash-unit.cpp:13: /home/bgreen/dev/git/edge-suite/ext/sparsehash/include/sparsehash/internal/libc_allocator_with_realloc.h:102:13: note: candidate: ?template<class T> bool google::operator==(const google::libc_allocator_with_realloc<U>&, const google::libc_allocator_with_realloc<U>&)? inline bool operator==(const libc_allocator_with_realloc<T>&, ^~~~~~~~ /home/bgreen/dev/git/edge-suite/ext/sparsehash/include/sparsehash/internal/libc_allocator_with_realloc.h:102:13: note: template argument deduction/substitution failed: In file included from /home/bgreen/dev/git/edge-suite/ext/googletest/include/gtest/gtest.h:58, from /home/bgreen/dev/git/edge-suite/baselib/test/unit/ext/sparsehash-unit.cpp:11: /home/bgreen/dev/git/edge-suite/baselib/test/unit/ext/sparsehash-unit.cpp:22:41: note: ?google::dense_hash_map<unsigned int, std::basic_string<char> >::iterator? {aka ?google::dense_hashtable_iterator<std::pair<const unsigned int, std::basic_string<char> >, unsigned int, std::hash<unsigned int>, google::dense_hash_map<unsigned int, std::basic_string<char> >::SelectKey, google::dense_hash_map<unsigned int, std::basic_string<char> >::SetKey, std::equal_to<unsigned int>, google::libc_allocator_with_realloc<std::pair<const unsigned int, std::basic_string<char> > > >?} is not derived from ?const google::libc_allocator_with_realloc<U>? EXPECT_TRUE(map.find(1) == map.cend());