This is my first time making a make file. I'm a little confused since my Fortran code uses some functions defined in C source files. This is what I've written so far: 

```
      CC = icc
      FC = ifort
      FCFLAGS = -O3 -xHost -fno-alias$(INCLUDES)
      CFLAGS = -O3 -xHost -fno-alias$(INCLUDES)
      LIBS =
      INCLUDES =
      TARGET = run
      OBJS: pi.o\
      timing.o
      timing.o: timing.c timing.h 
    $(CC) -c $(CFLAGS) timing.c
             pi.o:  pi.f90 timing.c timing.h 
         $(FC) -c $(FCFLAGS) timing.o pi.f90
            .PHONY : clean
             clean: rm -f *.o

```

Am I on the right track?