²Ù×÷ϵͳѧϰ±Ê¼Ç(14) CºÍ»ã±àÏ໥µ÷ÓÃ

; ±àÒëÁ´½Ó·½·¨
; (ld µÄ‘-s’Ñ¡ÏîÒâΪ“strip all”)
; gcc -c not link
;
; [root@XXX XXX]# nasm -f elf foo.asm -o foo.o
; [root@XXX XXX]# gcc -c bar.c -o bar.o
; [root@XXX XXX]# ld -s foo.o bar.o -o foobar
; [root@XXX XXX]# ./foobar
; the 2nd one
; [root@XXX XXX]#
extern choose ; int choose(int a, int b);
[section .data] ; Êý¾ÝÔÚ´Ë
num1st dd 3
num2nd dd 4
[section .text] ; ´úÂëÔÚ´Ë
global _start ; ÎÒÃDZØÐëµ¼³ö _start Õâ¸öÈë¿Ú£¬ÒÔ±ãÈÃÁ´½ÓÆ÷ʶ±ð¡£
global myprint ; µ¼³öÕâ¸öº¯ÊýΪÁËÈà bar.c ʹÓÃ
_start:
push num2nd ; ©·
push num1st ; ©§
call choose ; ©Ç choose(num1st, num2nd);
add esp, 4 ; ©¿
mov ebx, 0
mov eax, 1 ; sys_exit
int 0x80 ; ϵͳµ÷ÓÃ
; void myprint(char* msg, int len)
myprint:
mov edx, [esp + 8] ; len
mov ecx, [esp + 4] ; msg
mov ebx, 1
mov eax, 4 ; sys_write
int 0x80 ; ϵͳµ÷ÓÃ
ret


void myprint(char* msg, int len);
int choose(int a, int b)
{
if(a >= b){
myprint("the 1st one\n", 13);
}
else{
myprint("the 2nd one\n", 13);
}
return 0;
}

[root@localhost testc]# nasm -f elf foo.asm -o foo.o
[root@localhost testc]# gcc -c bar.c -o bar.o
[root@localhost testc]# ld -s foo.o bar.o -o foobar
[root@localhost testc]# ./foobar
the 2nd one
[root@localhost testc]#

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