Re: Problem using bitset bit access

[Meenaradchagan Vishnu <mvishnu at fore dot com>]

Here is a simple testcase that fails to compile:



#include <hash_map>  // if I don't include this, I get "`CHAR_BIT' was not
//declared in this scope" error several times.
#include <iostream>
#include <bitset>

int main()
  {
    bitset<191> b;

    b[ 1 ] = 5;

    cout << b[ 1 ] << endl;
  }



This gives the following compile error messages:

[leapfrog:~] g++ -c test_bitset.cc
/usr/local/lib/gcc-lib/sparc-sun-solaris2.5.1/2.95.1/../../../../include/g++-3/b
itset: In method `bitset<191,long unsigned 
int>::reference::reference(bitset<191,long unsigned int> &, unsigned int)':
/usr/local/lib/gcc-lib/sparc-sun-solaris2.5.1/2.95.1/../../../../include/g++-3/b
itset:751:   instantiated from `bitset<191,long unsigned int>::operator 
[](unsigned int)'
test_bitset.cc:10:   instantiated from here
/usr/local/lib/gcc-lib/sparc-sun-solaris2.5.1/2.95.1/../../../../include/g++-3/b
itset:91: `long unsigned int & _Base_bitset<6,long unsigned 
int>::_M_getword(unsigned int)' is inaccessible
/usr/local/lib/gcc-lib/sparc-sun-solaris2.5.1/2.95.1/../../../../include/g++-3/b
itset:581: within this context
[leapfrog:~] 

(Note:  I temporarily "fixed" the problem by changing line 533 of 
/usr/local/include/g++-3/bitset to

template<size_t _Nb, class _WordT = unsigned long>
class bitset : public _Base_bitset<__BITSET_WORDS(_Nb,_WordT), _WordT>

(i.e., from private inheritance to public inheritance.)