linux_kernel/include/asm-x86_64/bug.h

#ifndef __ASM_X8664_BUG_H
#define __ASM_X8664_BUG_H 1

#include <linux/stringify.h>

/*
 * Tell the user there is some problem.  The exception handler decodes 
 * this frame.
 */
struct bug_frame {
       unsigned char ud2[2];
	/* should use 32bit offset instead, but the assembler doesn't 
	   like it */
	char *filename;
	unsigned short line;
} __attribute__((packed));

#define HAVE_ARCH_BUG
#define BUG() \
	asm volatile("ud2 ; .quad %c1 ; .short %c0" :: \
		     "i"(__LINE__), "i" (__stringify(__FILE__)))
void out_of_line_bug(void);
#include <asm-generic/bug.h>

#endif