error with tr1 unordered_map iterator

Quote:

>, std::pair<const std::basic_string<char, std::char_traits<char>,

Quote:

Hi,

Quote:

I am using tr1/unordered_map in my code.

Quote:

My code compiled ok on g++ (GCC) 4.1.2 (Ubuntu 4.1.2-0ubuntu1). Now I
need to compile my code on g++ (GCC) 4.0.3 (Ubuntu 4.0.3-1ubuntu5).

Quote:

I get a messy error. Here are what I try to do:

Quote:

typedef unordered_map<string, unsignedStringHash;
...
StringHash::const_iterator word_pos;

Quote:

I get the error when I create the const_iterator:

Quote:

index.cc:161: error: no matching function for call to
'Internal::hashtable_iterator<std::pair<const std::basic_string<char,
std::char_traits<char>, std::allocator<char, unsigned int>, true,
false>::hashtable_iterator()'

Quote:

Removing const from the iterator does not make any difference.

Quote:

I tried to add const to string:

Quote:

typedef unordered_map<const string, unsignedStringHash;
...
typedef set<unsignedWordLevelEntrySet;
typedef pair<StringHash::const_iterator, WordLevelEntrySet>
WordLevelEntry;

Quote:

And the error moves to another place but is also on const_iterator:

Quote:

/usr/lib/gcc/i486-linux-gnu/4.0.3/../../../../include/c++/4.0.3/tr1/hashtable:
In instantiation of 'Internal::hash_code_base<const
std::basic_string<char, std::char_traits<char>, std::allocator<char>
, std::pair<const std::basic_string<char, std::char_traits<char>,
std::allocator<char, unsigned int>,
Internal::extract1st<std::pair<const std::basic_string<char,
std::char_traits<char>, std::allocator<char, unsigned int,
std::equal_to<const std::basic_string<char, std::char_traits<char>,
std::allocator<char >, std::tr1::hash<const std::basic_string<char,
std::char_traits<char>, std::allocator<char >,
Internal::mod_range_hashing, Internal::default_ranged_hash, false>':

Quote:

Is probably something that has been fixed or improved between the
versions. Is there any workaround?

Quote:

Thanks a lot,
Ray

Quote:

Quote:

Quote:

Quote:

Quote:

Quote:

Quote:

>>Rares Vernica wrote:
>>>Hi,
>>>I am using tr1/unordered_map in my code.
>>>My code compiled ok on g++ (GCC) 4.1.2 (Ubuntu 4.1.2-0ubuntu1). Now I
>>>need to compile my code on g++ (GCC) 4.0.3 (Ubuntu 4.0.3-1ubuntu5).
>>>I get a messy error. Here are what I try to do:
>>>typedef unordered_map<string, unsignedStringHash;
>>>...
>>>StringHash::const_iterator word_pos;
>>>I get the error when I create the const_iterator:
>>>index.cc:161: error: no matching function for call to
>>>'Internal::hashtable_iterator<std::pair<const std::basic_string<char,
>>>std::char_traits<char>, std::allocator<char, unsigned int>, true,
>>>false>::hashtable_iterator()'
>>>Removing const from the iterator does not make any difference.
>>>I tried to add const to string:
>>>typedef unordered_map<const string, unsignedStringHash;
>>>...
>>>typedef set<unsignedWordLevelEntrySet;
>>>typedef pair<StringHash::const_iterator, WordLevelEntrySet>
>>>WordLevelEntry;
>>>And the error moves to another place but is also on const_iterator:
>>>/usr/lib/gcc/i486-linux-gnu/4.0.3/../../../../include/c++/4.0.3/tr1/hashtable:
>>>In instantiation of 'Internal::hash_code_base<const
>>>std::basic_string<char, std::char_traits<char>, std::allocator<char>
>>>>, std::pair<const std::basic_string<char, std::char_traits<char>,
>>>std::allocator<char, unsigned int>,
>>>Internal::extract1st<std::pair<const std::basic_string<char,
>>>std::char_traits<char>, std::allocator<char, unsigned int,
>>>std::equal_to<const std::basic_string<char, std::char_traits<char>,
>>>std::allocator<char >, std::tr1::hash<const std::basic_string<char,
>>>std::char_traits<char>, std::allocator<char >,
>>>Internal::mod_range_hashing, Internal::default_ranged_hash, false>':
>>>Is probably something that has been fixed or improved between the
>>>versions. Is there any workaround?
>>>Thanks a lot,
>>>Ray
>>Woah this is way odd but based on my tests,
>>unordered_map::iterator has no default constructor.
>>This is what you seem to be encountering. I am not
>>sure if that is a bug on G++'s part or not or if
>>TR1 specifies that it need not be default constructible.
>>--------------------------------------------------------
>>#include <tr1/unordered_map>
>>#include <string>
>>using namespace std;
>>using namespace std::tr1;
>>typedef unordered_map<string, unsignedStringHash;
>>int
>>main()
>>{
>> StringHash myHashTable;
>> // assume you added some stuff in it
>> StringHash::const_iterator iter( myHashTable.begin() );
>>}