I get several compilation errors when compiling on LINUX (redhat and suse), compilers 2.95.3 and 3.3.1 The first that pops up is in G4MuBremsstrahlung.hh saying that the variable fParticleChange is undeclared. Looking in the code there is no declaration but the variable is used in the inline function SecondariesPostStep As I said there are more errors.....
Please, verify your installation is consistent. In the case you mention 'fParticleChange' is correctly declared in the base class G4VEnergyLossProcess. If you obtain compilation errors in the kernel libraries especially when using the supported platforms, it is more likely it's a problem in your setup.