compilation problem
isaac3
hello i am trying to compile this code w/ djgpp and nasm on win2k these are
the steps i use:
C:\CODE\asm\djgpp>nasmw -f coff first.asm
C:\CODE\asm\djgpp>gcc -o first.o driver.c asm_io.o
//but i get the following error when i try to do the 2nd step (gcc -o
first.o driver.c asm_io.o)
c:/djgpp/tmp\ccliaA1Z.o(.text+0x7):driver.c: undefined reference to
`asm_main'
collect2: ld returned 1 exit status
this is the code
//driver.c
/*------------------------------------------------------------------*/
int asm_main( void );
int main()
{
int ret_status;
ret_status = asm_main();
return ret_status;
}
/*-------------------------------------------------------------------*/
;
; file: first.asm
; First assembly program. This program asks for two integers as
; input and prints out their sum.
;
; To create executable:
; Using djgpp:
; nasm -f coff -d COFF_TYPE first.asm
; gcc -o first first.o driver.c asm_io.o
;
; Using Borland C/C++
; nasm -f obj -d OBJ_TYPE first.asm
; bcc32 first.obj driver.c asm_io.obj
%include "asm_io.inc"
;
; initialized data is put in the .data segment
;
segment .data
;
; These labels refer to strings used for output
;
prompt1 db "Enter a number: ", 0 ; don't forget nul terminator
prompt2 db "Enter another number: ", 0
outmsg1 db "You entered ", 0
outmsg2 db " and ", 0
outmsg3 db ", the sum of these is ", 0
;
; uninitialized data is put in the .bss segment
;
segment .bss
;
; These labels refer to double words used to store the inputs
;
input1 resd 1
input2 resd 1
;
; code is put in the .text segment
;
segment .text
global _asm_main
_asm_main:
enter 0,0 ; setup routine
pusha
mov eax, prompt1 ; print out prompt
call print_string
call read_int ; read integer
mov [input1], eax ; store into input1
mov eax, prompt2 ; print out prompt
call print_string
call read_int ; read integer
mov [input2], eax ; store into input2
mov eax, [input1] ; eax = dword at input1
add eax, [input2] ; eax += dword at input2
mov ebx, eax ; ebx = eax
dump_regs 1
dump_mem 2, outmsg1, 1
;
; next print out result message as series of steps
;
mov eax, outmsg1
call print_string ; print out first message
mov eax, [input1]
call print_int ; print out input1
mov eax, outmsg2
call print_string ; print out second message
mov eax, [input2]
call print_int ; print out input2
mov eax, outmsg3
call print_string ; print out third message
mov eax, ebx
call print_int ; print out sum (ebx)
call print_nl ; print new-line
popa
mov eax, 0 ; return back to C
leave
ret
;
; file: asm_io.asm
; Assembly I/O routines
; To assemble for DJGPP
; nasm -f coff -d COFF_TYPE asm_io.asm
; To assemble for Borland C++ 5.x
; nasm -f obj -d OBJ_TYPE asm_io.asm
; To assemble for Microsoft Visual Studio
; nasm -f win32 -d COFF_TYPE asm_io.asm
; To assemble for Linux
; nasm -f elf -d ELF_TYPE asm_io.asm
%define NL 10
;
; Linux C doesn't put underscores on labels
;
%ifdef ELF_TYPE
%define _scanf scanf
%define _printf printf
%define _getchar getchar
%define _putchar putchar
%endif
%ifdef OBJ_TYPE
segment .data public align=4 class=data use32
%else
segment .data
%endif
int_format db "%i", 0
string_format db "%s", 0
reg_format db "Register Dump # %d", NL
db "EAX = %.8X EBX = %.8X ECX = %.8X EDX = %.8X", NL
db "ESI = %.8X EDI = %.8X EBP = %.8X ESP = %.8X", NL
db "EIP = %.8X FLAGS = %.2X", NL
db 0
mem_format1 db "Memory Dump # %d Address = %.8X", NL, 0
mem_format2 db "%.8X ", 0
mem_format3 db "%.2X ", 0
stack_format db "Stack Dump # %d", NL
db "EBP = %.8X ESP = %.8X", NL, 0
stack_line_format db "%+4d %.8X %.8X", NL, 0
math_format1 db "Math Coprocessor Dump # %d Control Word = %.4X"
db " Status Word = %.4X", NL, 0
valid_st_format db "ST%d: %.10g", NL, 0
invalid_st_format db "ST%d: Invalid ST", NL, 0
empty_st_format db "ST%d: Empty", NL, 0
;
; code is put in the _TEXT segment
;
%ifdef OBJ_TYPE
segment text public align=1 class=code use32
%else
segment .text
%endif
global read_int, print_int, print_string, read_char
global print_char, print_nl, sub_dump_regs, sub_dump_mem
global sub_dump_math, sub_dump_stack
extern _scanf, _printf, _getchar, _putchar, _fputs
read_int:
enter 4,0
pusha
pushf
lea eax, [ebp-4]
push eax
push dword int_format
call _scanf
pop ecx
pop ecx
popf
popa
mov eax, [ebp-4]
leave
ret
print_int:
enter 0,0
pusha
pushf
push eax
push dword int_format
call _printf
pop ecx
pop ecx
popf
popa
leave
ret
print_string:
enter 0,0
pusha
pushf
push eax
push dword string_format
call _printf
pop ecx
pop ecx
popf
popa
leave
ret
read_char:
enter 4,0
pusha
pushf
call _getchar
mov [ebp-4], eax
popf
popa
mov eax, [ebp-4]
leave
ret
print_char:
enter 0,0
pusha
pushf
push eax
call _putchar
pop ecx
popf
popa
leave
ret
print_nl:
enter 0,0
pusha
pushf
push dword 10 ; 10 == ASCII code for \n
call _putchar
pop ecx
popf
popa
leave
ret
sub_dump_regs:
enter 0,0
pusha
pushf
mov eax, 0
lahf
shr eax, 8
push eax ; FLAGS
mov eax, [ebp+4]
sub eax, 10 ; EIP on stack is 10 bytes ahead of orig
push eax ; EIP
lea eax, [ebp+12]
push eax ; original ESP
push dword [ebp] ; original EBP
push edi
push esi
push edx
push ecx
push ebx
push dword [ebp-4] ; original EAX
push dword [ebp+8] ; # of dump
push dword reg_format
call _printf
add esp, 48
popf
popa
leave
ret 4
sub_dump_stack:
enter 0,0
pusha
pushf
lea eax, [ebp+20]
push eax ; original ESP
push dword [ebp] ; original EBP
push dword [ebp+8] ; # of dump
push dword stack_format
call _printf
add esp, 16
mov ebx, [ebp] ; ebx = original ebp
mov eax, [ebp+16] ; eax = # dwords above ebp
shl eax, 2 ; eax *= 4
add ebx, eax ; ebx = & highest dword in stack to display
mov edx, [ebp+16]
mov ecx, edx
add ecx, [ebp+12]
inc ecx ; ecx = # of dwords to display
stack_line_loop:
push edx
push ecx ; save ecx & edx
push dword [ebx] ; value on stack
push ebx ; address of value on stack
mov eax, edx
sal eax, 2 ; eax = 4*edx
push eax ; offset from ebp
push dword stack_line_format
call _printf
add esp, 16
pop ecx
pop edx
sub ebx, 4
dec edx
loop stack_line_loop
popf
popa
leave
ret 12
sub_dump_mem:
enter 0,0
pusha
pushf
push dword [ebp+12]
push dword [ebp+16]
push dword mem_format1
call _printf
add esp, 12
mov esi, [ebp+12] ; address
and esi, 0FFFFFFF0h ; move to start of paragraph
mov ecx, [ebp+8]
inc ecx
mem_outer_loop:
push ecx
push esi
push dword mem_format2
call _printf
add esp, 8
xor ebx, ebx
mem_hex_loop:
xor eax, eax
mov al, [esi + ebx]
push eax
push dword mem_format3
call _printf
add esp, 8
inc ebx
cmp ebx, 16
jl mem_hex_loop
mov eax, '"'
call print_char
xor ebx, ebx
mem_char_loop:
xor eax, eax
mov al, [esi+ebx]
cmp al, 32
jl non_printable
cmp al, 126
jg non_printable
jmp short mem_char_loop_continue
non_printable:
mov eax, '?'
mem_char_loop_continue:
call print_char
inc ebx
cmp ebx, 16
jl mem_char_loop
mov eax, '"'
call print_char
call print_nl
add esi, 16
pop ecx
loop mem_outer_loop
popf
popa
leave
ret 12
; function sub_dump_math
; prints out state of math coprocessor without modifying the coprocessor
; or regular processor state
; Parameters:
; dump number - dword at [ebp+8]
; Local variables:
; ebp-108 start of fsave buffer
; ebp-116 temp double
; Notes: This procedure uses the Pascal convention.
; fsave buffer structure:
; ebp-108 control word
; ebp-104 status word
; ebp-100 tag word
; ebp-80 ST0
; ebp-70 ST1
; ebp-60 ST2 ...
; ebp-10 ST7
;
sub_dump_math:
enter 116,0
pusha
pushf
fsave [ebp-108] ; save coprocessor state to memory
mov eax, [ebp-104] ; status word
and eax, 0FFFFh
push eax
mov eax, [ebp-108] ; control word
and eax, 0FFFFh
push eax
push dword [ebp+8]
push dword math_format1
call _printf
add esp, 16
;
; rotate tag word so that tags in same order as numbers are
; in the stack
;
mov cx, [ebp-104] ; ax = status word
shr cx, 11
and cx, 7 ; cl = physical state of number on stack top
mov bx, [ebp-100] ; bx = tag word
shl cl,1 ; cl *= 2
ror bx, cl ; move top of stack tag to lowest bits
mov edi, 0 ; edi = stack number of number
lea esi, [ebp-80] ; esi = address of ST0
mov ecx, 8 ; ecx = loop counter
tag_loop:
push ecx
mov ax, 3
and ax, bx ; ax = current tag
or ax, ax ; 00 -> valid number
je valid_st
cmp ax, 1 ; 01 -> zero
je zero_st
cmp ax, 2 ; 10 -> invalid number
je invalid_st
push edi ; 11 -> empty
push dword empty_st_format
call _printf
add esp, 8
jmp short cont_tag_loop
zero_st:
fldz
jmp short print_real
valid_st:
fld tword [esi]
print_real:
fstp qword [ebp-116]
push dword [ebp-112]
push dword [ebp-116]
push edi
push dword valid_st_format
call _printf
add esp, 16
jmp short cont_tag_loop
invalid_st:
push edi
push dword invalid_st_format
call _printf
add esp, 8
cont_tag_loop:
ror bx, 2 ; mov next tag into lowest bits
inc edi
add esi, 10 ; mov to next number on stack
pop ecx
loop tag_loop
frstor [ebp-108] ; restore coprocessor state
popf
popa
leave
ret 4
Get the FAQs http://www2.dgsys.com/~raymoon/x86faqs.html
Ed L Cashin
isaac3 <isa...@swbell.net> writes:
> hello i am trying to compile this code w/ djgpp and nasm on win2k these are
> the steps i use:
>
> C:\CODE\asm\djgpp>nasmw -f coff first.asm
> C:\CODE\asm\djgpp>gcc -o first.o driver.c asm_io.o
The -o flag tells gcc what the output file should be. But you have
told gcc to make first.o the output file.
> //but i get the following error when i try to do the 2nd step (gcc -o
> first.o driver.c asm_io.o)
>
> c:/djgpp/tmp\ccliaA1Z.o(.text+0x7):driver.c: undefined reference to
> `asm_main'
> collect2: ld returned 1 exit status
It's because first.asm has asm_main's definition. You need to link
the object code from the compiled first.o with the driver:
nasmw -f coff -w+macro-params -w+orphan-labels -o first.o first.asm
gcc -Wall -o driver.o -c driver.c
gcc -o myprogram first.o driver.o
Make will handle these complexities for you:
PROG = myprog
OBJ = driver.o first.o
CC = gcc
CFLAGS = -Wall -g
$(PROG) : $(OBJ)
$(CC) -o $@ $(OBJ)
driver.o : driver.c makefile
$(CC) $(CFLAGS) -c $< -o $@
%.o : %.asm makefile
nasm -f elf -w+macro-params -w+orphan-labels -o $@ $<
clean :
rm -f $(OBJ) $(PROG)
--
--Ed Cashin integrit file-verification system:
eca...@coe.uga.edu http://integrit.sourceforge.net/
Note: If you want me to send you email, don't munge your address
Frank Kotler
isaac3 wrote:
>
> hello i am trying to compile this code w/ djgpp and nasm on win2k these are
> the steps i use:
>
> C:\CODE\asm\djgpp>nasmw -f coff first.asm
> C:\CODE\asm\djgpp>gcc -o first.o driver.c asm_io.o
>
> //but i get the following error when i try to do the 2nd step (gcc -o
> first.o driver.c asm_io.o)
>
> c:/djgpp/tmp\ccliaA1Z.o(.text+0x7):driver.c: undefined reference to
> `asm_main'
I think the root of your problem is that, unlike most compilers, gcc
*doesn't* add the underscore. Try just "asm_main" in the .asm file (or
"_asm_main" in the "C" file).
As Ed Cashin points out, you also want "-o first.exe", not "-o first.o"
- some of the rest of his reply relates more to "real" gcc, and may not
work the same in DJGPP...
HTH,
Fran