circular buffer reports warning: " type qualifiers ignored on function return type" while compile.

[alps_xing@…]

If using circular in my application, GCC will report warning as:

../../../packages/target/libboost_1_49_0/include/boost/circular_buffer/base.hpp:386: warning: type qualifiers ignored on function return type
../../../packages/target/libboost_1_49_0/include/boost/circular_buffer/base.hpp:424: warning: type qualifiers ignored on function return type
../../../packages/target/libboost_1_49_0/include/boost/circular_buffer/base.hpp:478: warning: type qualifiers ignored on function return type
../../../packages/target/libboost_1_49_0/include/boost/circular_buffer/base.hpp:496: warning: type qualifiers ignored on function return type

I think it's caused by the "const" decorator.

[viboes]

I suspect that this need a change in boost/detail/call_traits.hpp

The following

template <typename T>
struct ct_imp2<T, true>
{
   typedef const T param_type;
};

should be

template <typename T>
struct ct_imp2<T, true>
{
   typedef T param_type;
};

[John Maddock]

I'm unable to reproduce here - anyone have a test case?

In any case, circular_buffer is abusing call_traits::param_type which is designed for parameters and not return values. And yes it really should be const ;-)

Use call_traits::value_type or call_traits::const_reference for those return types (I think I would settle for the latter).

[viboes]

You are right. As the documentation states, the return type should be const_reference.

[viboes]

Committed revision [84971].