Mine

	.file	"colon-op-test.c"
	.text
	.p2align 2,,3
.globl main
	.type	main, @function
main:
	pushl	%ebp
	movl	%esp, %ebp
	subl	$8, %esp
	andl	$-16, %esp
	movl	$0, %eax
	addl	$15, %eax
	addl	$15, %eax
	shrl	$4, %eax
	sall	$4, %eax
	subl	%eax, %esp
	subl	$12, %esp
	pushl	$1
	call	malloc
	addl	$16, %esp
	movl	%eax, -4(%ebp)
	movl	-4(%ebp), %edx
	movb	(%edx), %al
	andl	$-16, %eax
	orl	$1, %eax
	movb	%al, (%edx)
	movl	-4(%ebp), %edx
	movb	(%edx), %al
	andl	$15, %eax
	movb	%al, (%edx)
	movl	$0, %eax
	leave
	ret
	.size	main, .-main
	.ident	"GCC: (GNU) 3.4.6 [FreeBSD] 20060305"