Day 12 Makefiles Continued

1
Day 12Makefiles Continued

• David A. Gaitros
• Department of Computer Science
• Florida State University

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Exercise on Building Makefiles

• Assume you have a C program comprised of two
  files.
• main.c main program.
• util.h contains only the prototypes of the
  subroutines in util.c
• util.c contains the subroutines used in main.c
• util.c must be compiled before main.c because it
  must use the routines in util.c as part of its
  program.
• Once util.c is compiled, we can compile main.c
  using the generated object code (util.o)

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Exercise on Building Makefiles

• Here is how you would do it manually
• gcc -c util.h
• gcc -o main.x main.c util.o
• The -c option in the first line tells the
  compiler not to link the program.
• The -o option in the second line tells the
  compiler to name the output program main.x.
  Otherwise it would name it a.out.

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Exercise in Building a Makefile

• Here is what the makefile would look like.
• main.x main.c util.o
• gcc -o main.x main.c util.o
• util.o util.c util.h
• gcc -c util.c
• NOTE there are tabs before the gcc commands.

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Examples of Makefiles

• CC g
• myprogram.x myprogram.o gradebook.o
• (CC) -lcurses -o myprogram.x gradebook.o
  myprogram.o
• myprogram.o myprogram.cpp
• (CC) -c -I. -g -o myprogram.o myprogram.cpp
• gradebook.o gradebook.cpp gradebook.h
• (CC) -c -I. -g -o gradebook.o gradebook.cpp

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Examples of Makefiles

• CC gcc
• DIR /home/faculty/whalley/public_html/cop5622pro
  j/lib
• CFLAGS -g -I(DIR) -I. -c
• LFLAGS -g
• opt analysis.o flow.o io.o misc.o opt.o opts.o
  peephole.o regs.o vect.o
• (CC) (LFLAGS) -o opt analysis.o flow.o io.o
  misc.o opt.o opts.o peephole.o regs.o vect.o
• analysis.o analysis.c analysis.h (DIR)/misc.h
  (DIR)/opt.h (DIR)/vect.h
• (CC) (CFLAGS) analysis.c
• flow.o (DIR)/flow.c (DIR)/flow.h (DIR)/opt.h
• (CC) (CFLAGS) (DIR)/flow.c
• io.o (DIR)/io.c (DIR)/io.h analysis.h
  (DIR)/misc.h (DIR)/opt.h peephole.h
  (DIR)/regs.h
• (CC) (CFLAGS) (DIR)/io.c
• misc.o (DIR)/misc.c (DIR)/misc.h (DIR)/opt.h
• (CC) (CFLAGS) (DIR)/misc.c