missing prototype stm8 in stvd with cosmic

谁能告诉这个main.c编译出错是应为什么原因？？？？？如果删除func()则编译通过
环境：win7  stm8s103f3   stvd   cosmic


//main.c
int var;
void func(){
        var ++;
}
main(){
        var = 0;
        func();   //#error cpstm8 ..\..\source\main.c:14(2) missing prototype
        while (1)func(); //#error cpstm8 ..\..\source\main.c:14(2) missing prototype
}
----------- Project ikea25wdim - STM8 Cosmic - Configuration Debug -------------

Compiling ..\..\source\main.c...
cxstm8 +debug -pxp -no -l +mods0 -pp -i"C:\Program Files\COSMIC\CXSTM8_32K\Hstm8"  -clDebug\ -coDebug\ ..\..\source\main.c
#error cpstm8 ..\..\source\main.c:14(2) missing prototype
#error cpstm8 ..\..\source\main.c:15(11) missing prototype
..\..\source\main.c:
The command: "cxstm8 +debug -pxp -no -l +mods0 -pp -i"C:\Program Files\COSMIC\CXSTM8_32K\Hstm8"  -clDebug\ -coDebug\ ..\..\source\main.c " has failed, the returned value is: 1
exit code=1.