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gcc assembly output

poda19 (14)
hi
i am practicing reversing programs and i thought it would be helpful to view the assembly code of my own programs to learn about how they look in assembly. i used the -S flag with gcc compiler wich produces the assembly code of program. but the code doesn't look like those in debuggers.
it's something like this:
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	.file	"interest.cpp"
.lcomm __ZStL8__ioinit,1,1
	.text
.globl __Z9calculatefif
	.def	__Z9calculatefif;	.scl	2;	.type	32;	.endef
__Z9calculatefif:
	pushl	%ebp
	movl	%esp, %ebp
	subl	$20, %esp
	movl	$0x00000000, %eax
	movl	%eax, -8(%ebp)
	movl	$0, -12(%ebp)
	jmp	L2
L3:
	flds	16(%ebp)
	fmuls	8(%ebp)
	flds	LC1
	fdivrp	%st, %st(1)
	fstps	-4(%ebp)
	flds	16(%ebp)
	fadds	-4(%ebp)
	fstps	16(%ebp)
	flds	-8(%ebp)
	fadds	-4(%ebp)
	fstps	-8(%ebp)
	incl	-12(%ebp)

what are these codes? are they ASM? the assembly code i see in debugger (ollydbg) is something like this:
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PUSH EBP
MOV EBP,ESP
SUB ESP,18
MOV DWORD PTR SS:[ESP],1
CALL DWORD PTR DS:[<&msvcrt.__set_app_type>]      CALL interest.00401020
NOP
LEA ESI,DWORD PTR DS:[ESI]
PUSH EBP
MOV EBP,ESP
PUSH EBX
SUB ESP,14
MOV EAX,DWORD PTR SS:[EBP+8]

is there any way to tell the compiler produce these kind of codes for my program?
thanks
Last edited on
poda19 (14)
ok i got it
it was the AT&T syntax i sould use -S -masm=intel to produce intel code
thanks anyway
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