Miscellany

### MakeFile ######
CXX=g++
OPTS=-Wall
OBJS=foo.o main.o

foo: ${OBJS}
        ${CXX} ${OPTS} -o foo ${OBJS}

main.o: foo.h main.cc
        ${CXX} ${OPTS} -c main.cc

foo.o: foo.h foo.cc
        ${CXX} ${OPTS} -c foo.cc#include "foo.h"

### foo.cc ###
void foo()
{
         int arr[10];
         arr[0] = 10;
}

### foo.h ###
#ifndef _FOO_H_
#define _FOO_H_

extern int arr[10];

void foo();

#endif

### main.c ###
#include "foo.h"

int main(int argc, char ** argv)
{
         int arr[10];
         arr[0] = 0;
         return 0;
}