Thanks for the quick response, David.
Indeed, I have just tried rebuilding the systemc libs and the example with gcc 7.5 and it worked!
Actually, when I chose 4.8 for the compiler version I was only following the README info for the 2.3.1 release where it states "GNU C++ compiler versions gcc-3.4.6 through gcc-4.9.0" as "well tested" configurations for GCC.
But if systemc can as well be used with newer GCCs, I will stick to those of course.