I have a problem with g++ 4.3.2 in -std=c++0x mode.
Here is some code which works fine:
typedef std::map<Key, My_data, Compare> My_Map; (***)
typedef typename My_map::iterator My_iterator;
// data members
typedef std::map<Key, My_data, Compare> My_Map;
Note, that it uses My_data as the data_value for the std::map type
defined in the My_data struct *itself*.
This works fine. But now I want to change std::map by
So do I, with appropriate hash function and Equality comparator.
But then, g++ 4.3.2 gives me the following error:
error: no type named ?iterator? in ?class std::unordered_map<...'
at line (***). I know this does come from the fact that I'm using
My_data as a template parameter inside the definition of the struct
But... it did work for std::map... so why shouldn't it work for
Is there a workaround ? is this a bug of libstd++ ?
Thank you very much !
This may have changed in C++0X (I haven't checked), but in the 2003
standard what you are doing is undefined behavior. You cannot
instantiate a template component for any of the standard library
templates with an incomplete type. Within the definition of My_data,
My_data is an incomplete type.
Reference 188.8.131.52.2 in the 2003 standard.
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