Mixed-Language Programming (The GNU Fortran Compiler) (original) (raw)

This chapter is about mixed-language interoperability, but also applies if you link Fortran code compiled by different compilers. In most cases, use of the C Binding features of the Fortran 2003 and later standards is sufficient.

For example, it is possible to mix Fortran code with C++ code as well as C, if you declare the interface functions as extern "C" on the C++ side and BIND(C) on the Fortran side, and follow the rules for interoperability with C. Note that you cannot manipulate C++ class objects in Fortran or vice versa except as opaque pointers.

You can use the gfortran command to link both Fortran and non-Fortran code into the same program, or you can use gccor g++ if you also add an explicit -lgfortran option to link with the Fortran library. If your main program is written in C or some other language instead of Fortran, seeNon-Fortran Main Program, below.

• Interoperability with C
• GNU Fortran Compiler Directives
• Non-Fortran Main Program
• Naming and argument-passing conventions