The recent 10.02 release ships a patched version of G4AnyMethod.hh which makes use of the definitions of remove_reference given in the standard header type_traits when compiling with support for c++11. This header in my system (gcc 5.2) defines these three prototypes: template<typename _Tp> struct remove_reference { typedef _Tp type; }; template<typename _Tp> struct remove_reference<_Tp&> { typedef _Tp type; }; template<typename _Tp> struct remove_reference<_Tp&&> { typedef _Tp type; }; The old pre-c++11 implementation in G4AnyMethod.hh defines these: template<typename T> struct remove_reference {typedef T type;}; template<typename T> struct remove_reference<T&> {typedef T type;}; template<typename T> struct remove_reference<const T&> {typedef T type;}; The third definition is different, and in particular it also removes the const qualifier. The net effect is that when compiling with c++11 support it is not possible to call G4GenericMessenger::SetMethod using as second argument a method which takes a const argument, since at line 185 of G4AnyMethod.hh the rhs variable a0 is const and the compiler gives an error. This does not happen when compiling with the c++98 standard.
Created attachment 368 [details] Explicitly remove constness with remove_const A very simple fix is to explicitly remove constness by means of remove_const. This is a C++11 feature but it's very simple to implement also for C++98 like what was done for remove_reference. I attach a patch which does exactly this. It works on my system when using C++11, I didn't test it with C++98 since I didn't find a way to force C++98 (CMake only accepts 11 or 14 as possible options). Feel free to use it as you like.
The suggested fix was applied in Geant4 development version and will be available in the next release, 10.4. Closing.
