stdbool.h is C99 specific. Codewarrior does not implement C99.
stdtypes.h is not standard at all.
My advice would be to write your own h-file:
#ifndef _BOOL_H
#define _BOOL_H
typedef unsigned char BOOL;
#define FALSE 0
#define TRUE 1
#endif
Or with typedef enum{FALSE, TRUE}BOOL, but that would be less efficient since enum is likely 16-bit.