topic Link Error: L1822: Symbol MCU_init__Fv in file main.cpp.o is undefined in Classic/Legacy CodeWarrior

Link Error: L1822: Symbol MCU_init__Fv in file main.cpp.o is undefined

JOTAEME — Tue, 30 Oct 2007 04:41:19 GMT

I'm getting this message when I try to compile a project, but I'm using Device Initialization, so I don't know why it can't find a symbol it's supposed to be defined automatically.
I already worked in a different project with the same version of CodeWarrior and did the same procedure to create the project, and never got that error. The only difference is that I used the MC9S08GT60A, wich I got to flash program it fine and with no problems. Now, I'm trying to flash program the MC9S08GT16 and, as I said before, it brings up this error.
Does anybody know why is this?

Re: Link Error: L1822: Symbol MCU_init__Fv in file main.cpp.o is undefined

CrasyCat — Tue, 30 Oct 2007 15:30:45 GMT

Hello

This is due to the C++ name mangling.

Device Initialization is generating ANSI C source code and you are trying to call an ANSI C function from a C++ module.

You have to let the compiler know that the function MCU_init is an ANSI C function.

Just enclose the MCU_init function prototype between

#ifdef __cplusplus
extern "C" {
#endif

and

#ifdef __cplusplus
}
#endif

Example

#ifdef __cplusplus
extern "C" {
#endif

void MCU_init(void);

#ifdef __cplusplus
}
#endif

I hope this helps.

CrasyCat

Re: Link Error: L1822: Symbol MCU_init__Fv in file main.cpp.o is undefined

yida — Thu, 21 Apr 2011 19:08:55 GMT

After I used the solution, I got a "C1073: Linkage specification contradicts earlier specification" instead. And I defined it only once.

#ifndef _HARDWARE_H_
#define _HARDWARE_H_

#ifdef __cplusplus
extern "C" {
#endif

void PLL_init();

#ifdef __cplusplus
}
#endif

#endif

What shall I do now?

Re: Link Error: L1822: Symbol MCU_init__Fv in file main.cpp.o is undefined

CrasyCat — Tue, 26 Apr 2011 18:52:21 GMT

Hello

First this seems to be a completely different topic.

Can you please post a new message for that.

Are you forcing compilation of whole application in C++?

Did you look at the preprocessing listing for the source file generating the message?

Do you have other definition/declaration for PLL_Init there?

CrasyCat