Combining C++ and fortran programs

[Toon Moene]

Friedhelm David wrote:

> I have C++-Programs that I want to call from Fortran.
> 
> The name of the function in the C++-Programm cp.C is foo. But when I
> compile the program with " g++ -c cp.C" then the name of the function
> foo in the object modul is foo__FPi. When I compile the Fortan-Program
> with "g77 -c -fno-underscoring fp.f", the name of the called subroutine
> in the Fortran object modul is foo.  When I link the programms with
> "g77 fp.o cp.o"I get the error message "undefined reference to `foo'".

The only way that I know of to link C++ functions successfully to
Fortran code is to declare them "extern C { ... }".

Unfortunately, I do not recall the exact syntax for that at present -
but it should be explained in the C++ part of the GCC manual.

Hope this helps,

-- 
Toon Moene - mailto:toon@moene.indiv.nluug.nl - phoneto: +31 346 214290
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