Undefined symbol linking cpp + c objects

[c.kirmse]

Hi,

i have searched the thread but i found no similar problem.
I try to link c and c++ objects compiled with carbide.c++ and i always get the linker error:

>Undefined symbol: 'int gsm_decode(struct gsm_state *, unsigned char *, short *) (?gsm_decode@@YAHPAUgsm_state@@PAEPAF@Z)'
>referenced from 'int CGSM::GSMToLinear(unsigned char const *, int, unsigned short *) (?GSMToLinear@CGSM@@QAEHPBEHPAG@Z)' in gsm.cpp:56

The c object exist and in the corresponding include file the label is also correct.
Pls any idea whats wrong ?

[wizard_hu_]

It seems to be a C to C++ linking problem. Have you actually surrounded your C-headers with extern "C" when you include them from C++?

[c.kirmse]

Thanks a lot (of course i forgot this)