White smoke ...
I succeeded in creating the Monte Carlo executable that links the CERN
library and the Tcl/Tk .a and .h files.
I just got rid of a macro that is proprietary for Sun Unix but it's
deleterius on Linux/Suse. The culprit is " -Df2cFortran".
This option was in the list of the CFLAGS and CXXFLAGS.
I realized it was junk when I launched "make -p".
This is a left-over from the installation procedure for Sun.
It's just amazing that "make" did not complain about it !
Thank you all for assisting me through this nightmare.