Parameters to external c-functions

Hello,

I'm having problems passing paramters to external c-functions.
For example I tried the follwing:

#include "eclipseclass.h"

...

extern "C" int p_dash(value v_power, tag t_power)  // Line 78
{

. ..

}

This produced an error during compile-time:

eclipse-robosoc.cc: At top level:
eclipse-robosoc.cc:78: type specifier omitted for parameter
eclipse-robosoc.cc:78: parse error before `)'

Maybe it has something to do with some warnings the compiler gives me 
when including eclipseclass:

usr/local/eclipse_5.1/include/i386_linux/eclipse_cc.h: In function 
`EC_word term (EC_functor, EC_word,
EC_word, EC_word, EC_word)':
/usr/local/eclipse_5.1/include/i386_linux/eclipse_cc.h:1872: warning: 
cannot pass objects of non-POD
type `const class EC_word' through `...'
/usr/local/eclipse_5.1/include/i386_linux/eclipse_cc.h:1872: warning: 
cannot pass objects of non-POD
type `const class EC_word' through `...'
/usr/local/eclipse_5.1/include/i386_linux/eclipse_cc.h:1872: warning: 
cannot pass objects of non-POD
type `const class EC_word' through `...'
/usr/local/eclipse_5.1/include/i386_linux/eclipse_cc.h:1872: warning: 
cannot pass objects of non-POD
type `const class EC_word' through `...'

and some more of this type

Does anyone know what I have to do?

Andreas