Using and Porting GNU Fortran
12.1.4 C++ Considerations
f2c can be used to generate suitable code for compilation with a
C++ system using the `-C++' option.
The important thing about linking
code with C++ is that the prototypes for the
routines must specify C linkage to avoid name mangling.
So, use an `extern "C"' declaration.
f2c's `-C++' option will take care
of this when generating skeletons or prototype files as above, and also
avoid clashes with C++ reserved words in addition to those in C.