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Bug 000375

When Created: 06/14/2005 04:44:34
Against DJGPP version: 2.03
By whom: huangxiangkui@msn.com
Abstract: A great error of djgpp,make a program with error.
I am a Chinese middle schoole student.

The code is below.

/*head.s start*/


	.code16
	.text
.global _start
_start:
	movw %cs,%ax
	movw %ax,%ds
	movw %ax,%es
	
	call _init
l:
	jmp l

/*head.s end*/

/*init.c start/

int vga_text(void);
int v(void);

int init(void)
{
	vga_text();
	v();
	return(0);
}

/*init.c end*/

/*tool.s start*/

	.code16
	.text
	.global _vga_text,_v
_vga_text:
	pushw %bp
	movw %sp,%bp
	
	movb $0x00,%ah
	movb $0x03,%al
	int $0x10

	popw %bx
	popw %es

	popw %bp
	ret

_v:
	pushw %bp
	movw %sp,%bp

	pushw %es
	pushw %bx

	movw $0xb800,%ax
	movw %ax,%es

	movb $'H',%es:0
	movb $0x0a,%es:1

	popw %bx
	popw %es
	
	popw %bp
	ret

/*tool.s end*/

#makefile.txt start#
CC=gcc
LD=ld
AFLAGS = -traditional -c -nostdinc
CFLAGS = -Wall -Wstrict-prototypes -O2 -fomit-frame-pointer
LDFLAGS= -e _start -Ttext 0x0000 -s --oformat binary

all:head.o init.o tool.o
	$(LD) $(LDFLAGSI) -o $@ head.o init.o tool.o

head.o:head.s
	$(CC) $(AFLAGS) -o $@ $<

init.o:init.c
	$(CC) $(CFLAGS) -c $< -o $@

tool.o:tool.s
	$(CC) $(AFLAGS) -o $@ $<

#makefile.txt end#


but the program doesn't do well.

I use NASM to turn the system to system.asm

ndisasm system > system.asm

;system.asm start

00000000  8CC8              mov ax,cs
00000002  8ED8              mov ds,ax
00000004  8EC0              mov es,ax
00000006  E80700            call 0x10
00000009  EBFE              jmp short 0x9
0000000B  90                nop
0000000C  90                nop
0000000D  90                nop
0000000E  90                nop
0000000F  90                nop
00000010  83EC0C            sub sp,byte +0xc
00000013  E81800            call 0x2e
00000016  0000              add [bx+si],al
00000018  E82000            call 0x3b
0000001B  0000              add [bx+si],al
0000001D  31C0              xor ax,ax
0000001F  83C40C            add sp,byte +0xc
00000022  C3                ret
00000023  90                nop
00000024  90                nop
00000025  90                nop
00000026  90                nop
00000027  90                nop
00000028  90                nop
00000029  90                nop
0000002A  90                nop
0000002B  90                nop
0000002C  90                nop
0000002D  90                nop
0000002E  90                nop
0000002F  90                nop
00000030  55                push bp
00000031  89E5              mov bp,sp
00000033  B400              mov ah,0x0
00000035  B003              mov al,0x3
00000037  CD10              int 0x10
00000039  5B                pop bx
0000003A  07                pop es
0000003B  5D                pop bp
0000003C  C3                ret
0000003D  55                push bp
0000003E  89E5              mov bp,sp
00000040  06                push es
00000041  53                push bx
00000042  B800B8            mov ax,0xb800
00000045  8EC0              mov es,ax
00000047  26C606000048      mov byte [es:0x0],0x48
0000004D  26C60601000A      mov byte [es:0x1],0xa
00000053  5B                pop bx
00000054  07                pop es
00000055  5D                pop bp
00000056  C3                ret
00000057  90                nop
00000058  90                nop
00000059  90                nop
0000005A  90                nop
0000005B  90                nop
0000005C  90                nop
0000005D  90                nop
0000005E  90                nop
0000005F  90                nop
00000060  0000              add [bx+si],al
00000062  0000              add [bx+si],al
00000064  0000              add [bx+si],al

;system.asm end

From the system.asm you can see where is error
It is on line 18

There Should be "call 0x3d",but now there is "call 0x3b"

I do feel that is a great error.



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