Intel to ATT Syntax: jmp

[rhollencamp]

I'm trying to convert the following code into a format that GNU as can understand. Here is the source:

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[GLOBAL gdt_flush]    ; Allows the C code to call gdt_flush().

gdt_flush:
   mov eax, [esp+4]  ; Get the pointer to the GDT, passed as a parameter.
   lgdt [eax]        ; Load the new GDT pointer

   mov ax, 0x10      ; 0x10 is the offset in the GDT to our data segment
   mov ds, ax        ; Load all data segment selectors
   mov es, ax
   mov fs, ax
   mov gs, ax
   mov ss, ax
   jmp 0x08:.flush   ; 0x08 is the offset to our code segment: Far jump!
.flush:
   ret

and here is my code:

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.global gdt_write

gdt_write:
	movl 4(%esp), %eax
	lgdt (%eax)

	mov 0x10, %ax
	mov %ax, %ds
	mov %ax, %es
	mov %ax, %fs
	mov %ax, %gs
	mov %ax, %ss
	jmp 0x08:flush
flush:
	ret

for the life of me, I can't figure out the jmp statement. It gives me a variety of errors depending on what I try, what is shown above gives the error ' Error: junk `:flush' after expression'.

Robert Hollencamp

[Combuster]

<insert propaganda against AT&T syntax>

the opcode is ljmp

[fieldofcows]

I think what you want is:

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jmp $0x08, $flush

Also, you're missing a dollar symbol on the following line:

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mov 0x10, %ax

should be:

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mov $0x10, %ax

Roy