Four phases of GCC compilation: preprocessing, compiling, compiling, linking

1: Four Phases of GCC compilation: preprocessing, compiling, compiling, linking

#vi file.c

#gcc-E file.c-o file.i//-e view and stop compiling after preprocessing,-o to generate the target file,- i means preprocessed

#gcc-S File.i-o file.s//-s compiled to assembly without assembly and linking

#gcc-C file.s-o file.o//-c compile to target code

#gcc file.o-o file//-o file output to a file

# gcc-static File.c-o file//-static Disable the use of dynamic libraries

; Makefile Basic Rules

1 All:test

2 echo "Hello World"

3 Test:

4 @echo "Hi Hi"

; with Tab Key Space

;all,test is the target

; 2,4 is the command that generates the target

#make ( default run 1), &make all, &make test

; Makefile Dependency Relationship

1 SIMPLE:MAIN.O foo.o BAR.O

2 gcc-o Simple MAIN.O foo.o bar.o// execute command

3 MAIN.O:MAIN.C

4 gcc-c main.c-o main.o// generate command

5 FOO.O:FOO.C

6 Gcc-c Foo.c-o FOO.O

7 BAR.O:BAR.C

8 Gcc-c Bar.c-o BAR.O

9 Clean:

RM *.o// clearly generated files

; Simple depends on:main.o foo.o BAR.O

Three . o files are also dependent on three . C files

#touch foo.c bar.c// do not write the main function, many times to define the error

#vi main.c// Write the main function

#make clean// execution

; false target: . Phony

1. Phony:clean

2 Test:

3 echo "Hello"

4 Clean:

5 RM *.c

; when the directory has other Clean you can use false targets when you are not associated with a file

; #vi test.c

#gcc-C test.c

# ls

TEST.c TEST.O ( target file )

#gcc-o Test ( executable file ) TEST.O

# ls

Test test.c TEST.O

; One main program calls another subroutine

# Cat TEST.c test2.c

#include <stdio.h>

int main ()

{printf (" Hello, I have the Lord \ \");

Test_2 ();

return 0;}

------------------------------------------

void test_2 (void)

{printf (" Thank you, you are also good!") \ n ");

return 0;}

# gcc-c TEST.c test2.c

test2.c test2.o test.c TEST.O

# Gcc-o Test TEST.O TEST2.O

Test test2.c test2.o test.c TEST.O

Four phases of GCC compilation: preprocessing, compiling, compiling, linking