一个C程序怎么就可以神奇的运行起来那？

#include <stdio.h>
/*这是注释*/
int main(void)
{
printf("hello world\n");
return 0;
}

# 1 "main.c"
# 1 "<built-in>"
# 1 "<command-line>"
# 1 "main.c"
# 1 "/usr/include/stdio.h" 1 3 4
# 28 "/usr/include/stdio.h" 3 4
# 1 "/usr/include/features.h" 1 3 4
# 323 "/usr/include/features.h" 3 4
# 1 "/usr/include/i386-linux-gnu/bits/predefs.h" 1 3 4
# 324 "/usr/include/features.h" 2 3 4
# 356 "/usr/include/features.h" 3 4
# 1 "/usr/include/i386-linux-gnu/sys/cdefs.h" 1 3 4
# 353 "/usr/include/i386-linux-gnu/sys/cdefs.h" 3 4
# 1 "/usr/include/i386-linux-gnu/bits/wordsize.h" 1 3 4
# 354 "/usr/include/i386-linux-gnu/sys/cdefs.h" 2 3 4
# 357 "/usr/include/features.h" 2 3 4
# 388 "/usr/include/features.h" 3 4
# 1 "/usr/include/i386-linux-gnu/gnu/stubs.h" 1 3 4

# 1 "/usr/include/i386-linux-gnu/bits/wordsize.h" 1 3 4
# 5 "/usr/include/i386-linux-gnu/gnu/stubs.h" 2 3 4

# 1 "/usr/include/i386-linux-gnu/gnu/stubs-32.h" 1 3 4
# 8 "/usr/include/i386-linux-gnu/gnu/stubs.h" 2 3 4
# 389 "/usr/include/features.h" 2 3 4
# 29 "/usr/include/stdio.h" 2 3 4

# 1 "/usr/lib/gcc/i686-linux-gnu/4.6.1/include/stddef.h" 1 3 4
# 212 "/usr/lib/gcc/i686-linux-gnu/4.6.1/include/stddef.h" 3 4
typedef unsigned int size_t;
# 35 "/usr/include/stdio.h" 2 3 4

# 1 "/usr/include/i386-linux-gnu/bits/types.h" 1 3 4
# 28 "/usr/include/i386-linux-gnu/bits/types.h" 3 4
# 1 "/usr/include/i386-linux-gnu/bits/wordsize.h" 1 3 4
# 29 "/usr/include/i386-linux-gnu/bits/types.h" 2 3 4

typedef unsigned char __u_char;
typedef unsigned short int __u_short;
typedef unsigned int __u_int;
typedef unsigned long int __u_long;

typedef signed char __int8_t;
typedef unsigned char __uint8_t;
typedef signed short int __int16_t;
typedef unsigned short int __uint16_t;
typedef signed int __int32_t;
typedef unsigned int __uint32_t;

__extension__ typedef signed long long int __int64_t;
__extension__ typedef unsigned long long int __uint64_t;

__extension__ typedef long long int __quad_t;
__extension__ typedef unsigned long long int __u_quad_t;
# 131 "/usr/include/i386-linux-gnu/bits/types.h" 3 4
# 1 "/usr/include/i386-linux-gnu/bits/typesizes.h" 1 3 4
# 132 "/usr/include/i386-linux-gnu/bits/types.h" 2 3 4

__extension__ typedef __u_quad_t __dev_t;
__extension__ typedef unsigned int __uid_t;
__extension__ typedef unsigned int __gid_t;
__extension__ typedef unsigned long int __ino_t;
__extension__ typedef __u_quad_t __ino64_t;
__extension__ typedef unsigned int __mode_t;
__extension__ typedef unsigned int __nlink_t;
__extension__ typedef long int __off_t;
__extension__ typedef __quad_t __off64_t;
__extension__ typedef int __pid_t;
__extension__ typedef struct { int __val[2]; } __fsid_t;
__extension__ typedef long int __clock_t;
__extension__ typedef unsigned long int __rlim_t;
__extension__ typedef __u_quad_t __rlim64_t;
__extension__ typedef unsigned int __id_t;
__extension__ typedef long int __time_t;
__extension__ typedef unsigned int __useconds_t;
__extension__ typedef long int __suseconds_t;

__extension__ typedef int __daddr_t;
__extension__ typedef long int __swblk_t;
__extension__ typedef int __key_t;

__extension__ typedef int __clockid_t;

__extension__ typedef void * __timer_t;

__extension__ typedef long int __blksize_t;

__extension__ typedef long int __blkcnt_t;
__extension__ typedef __quad_t __blkcnt64_t;

__extension__ typedef unsigned long int __fsblkcnt_t;
__extension__ typedef __u_quad_t __fsblkcnt64_t;

__extension__ typedef unsigned long int __fsfilcnt_t;
__extension__ typedef __u_quad_t __fsfilcnt64_t;

__extension__ typedef int __ssize_t;

typedef __off64_t __loff_t;
typedef __quad_t *__qaddr_t;
typedef char *__caddr_t;

__extension__ typedef int __intptr_t;

__extension__ typedef unsigned int __socklen_t;
# 37 "/usr/include/stdio.h" 2 3 4
# 45 "/usr/include/stdio.h" 3 4
struct _IO_FILE;

typedef struct _IO_FILE FILE;

# 65 "/usr/include/stdio.h" 3 4
typedef struct _IO_FILE __FILE;
# 75 "/usr/include/stdio.h" 3 4
# 1 "/usr/include/libio.h" 1 3 4
# 32 "/usr/include/libio.h" 3 4
# 1 "/usr/include/_G_config.h" 1 3 4
# 15 "/usr/include/_G_config.h" 3 4
# 1 "/usr/lib/gcc/i686-linux-gnu/4.6.1/include/stddef.h" 1 3 4
# 16 "/usr/include/_G_config.h" 2 3 4

# 1 "/usr/include/wchar.h" 1 3 4
# 83 "/usr/include/wchar.h" 3 4
typedef struct
{
int __count;
union
{

unsigned int __wch;

char __wchb[4];
} __value;
} __mbstate_t;
# 21 "/usr/include/_G_config.h" 2 3 4

typedef struct
{
__off_t __pos;
__mbstate_t __state;
} _G_fpos_t;
typedef struct
{
__off64_t __pos;
__mbstate_t __state;
} _G_fpos64_t;
# 53 "/usr/include/_G_config.h" 3 4
typedef int _G_int16_t __attribute__ ((__mode__ (__HI__)));
typedef int _G_int32_t __attribute__ ((__mode__ (__SI__)));
typedef unsigned int _G_uint16_t __attribute__ ((__mode__ (__HI__)));
typedef unsigned int _G_uint32_t __attribute__ ((__mode__ (__SI__)));
# 33 "/usr/include/libio.h" 2 3 4
# 53 "/usr/include/libio.h" 3 4
# 1 "/usr/lib/gcc/i686-linux-gnu/4.6.1/include/stdarg.h" 1 3 4
# 40 "/usr/lib/gcc/i686-linux-gnu/4.6.1/include/stdarg.h" 3 4
typedef __builtin_va_list __gnuc_va_list;
# 54 "/usr/include/libio.h" 2 3 4
# 170 "/usr/include/libio.h" 3 4
struct _IO_jump_t; struct _IO_FILE;
# 180 "/usr/include/libio.h" 3 4
typedef void _IO_lock_t;

struct _IO_marker {
struct _IO_marker *_next;
struct _IO_FILE *_sbuf;

int _pos;
# 203 "/usr/include/libio.h" 3 4
};

enum __codecvt_result
{
__codecvt_ok,
__codecvt_partial,
__codecvt_error,
__codecvt_noconv
};
# 271 "/usr/include/libio.h" 3 4
struct _IO_FILE {
int _flags;

char* _IO_read_ptr;
char* _IO_read_end;
char* _IO_read_base;
char* _IO_write_base;
char* _IO_write_ptr;
char* _IO_write_end;
char* _IO_buf_base;
char* _IO_buf_end;

char *_IO_save_base;
char *_IO_backup_base;
char *_IO_save_end;

struct _IO_marker *_markers;

struct _IO_FILE *_chain;

int _fileno;

int _flags2;

__off_t _old_offset;

unsigned short _cur_column;
signed char _vtable_offset;
char _shortbuf[1];

_IO_lock_t *_lock;
# 319 "/usr/include/libio.h" 3 4
__off64_t _offset;
# 328 "/usr/include/libio.h" 3 4
void *__pad1;
void *__pad2;
void *__pad3;
void *__pad4;
size_t __pad5;

int _mode;

char _unused2[15 * sizeof (int) - 4 * sizeof (void *) - sizeof (size_t)];

};

typedef struct _IO_FILE _IO_FILE;

struct _IO_FILE_plus;

extern struct _IO_FILE_plus _IO_2_1_stdin_;
extern struct _IO_FILE_plus _IO_2_1_stdout_;
extern struct _IO_FILE_plus _IO_2_1_stderr_;
# 364 "/usr/include/libio.h" 3 4
typedef __ssize_t __io_read_fn (void *__cookie, char *__buf, size_t __nbytes);

typedef __ssize_t __io_write_fn (void *__cookie, __const char *__buf,
size_t __n);

typedef int __io_seek_fn (void *__cookie, __off64_t *__pos, int __w);

typedef int __io_close_fn (void *__cookie);
# 416 "/usr/include/libio.h" 3 4
extern int __underflow (_IO_FILE *);
extern int __uflow (_IO_FILE *);
extern int __overflow (_IO_FILE *, int);
# 460 "/usr/include/libio.h" 3 4
extern int _IO_getc (_IO_FILE *__fp);
extern int _IO_putc (int __c, _IO_FILE *__fp);
extern int _IO_feof (_IO_FILE *__fp) __attribute__ ((__nothrow__));
extern int _IO_ferror (_IO_FILE *__fp) __attribute__ ((__nothrow__));

extern int _IO_peekc_locked (_IO_FILE *__fp);

extern void _IO_flockfile (_IO_FILE *) __attribute__ ((__nothrow__));
extern void _IO_funlockfile (_IO_FILE *) __attribute__ ((__nothrow__));
extern int _IO_ftrylockfile (_IO_FILE *) __attribute__ ((__nothrow__));
# 490 "/usr/include/libio.h" 3 4
extern int _IO_vfscanf (_IO_FILE * __restrict, const char * __restrict,
__gnuc_va_list, int *__restrict);
extern int _IO_vfprintf (_IO_FILE *__restrict, const char *__restrict,
__gnuc_va_list);
extern __ssize_t _IO_padn (_IO_FILE *, int, __ssize_t);
extern size_t _IO_sgetn (_IO_FILE *, void *, size_t);

extern __off64_t _IO_seekoff (_IO_FILE *, __off64_t, int, int);
extern __off64_t _IO_seekpos (_IO_FILE *, __off64_t, int);

extern void _IO_free_backup_area (_IO_FILE *) __attribute__ ((__nothrow__));
# 76 "/usr/include/stdio.h" 2 3 4

typedef __gnuc_va_list va_list;
# 91 "/usr/include/stdio.h" 3 4
typedef __off_t off_t;
# 103 "/usr/include/stdio.h" 3 4
typedef __ssize_t ssize_t;

typedef _G_fpos_t fpos_t;

# 161 "/usr/include/stdio.h" 3 4
# 1 "/usr/include/i386-linux-gnu/bits/stdio_lim.h" 1 3 4
# 162 "/usr/include/stdio.h" 2 3 4

extern struct _IO_FILE *stdin;
extern struct _IO_FILE *stdout;
extern struct _IO_FILE *stderr;

extern int remove (__const char *__filename) __attribute__ ((__nothrow__));

extern int rename (__const char *__old, __const char *__new) __attribute__ ((__nothrow__));

extern int renameat (int __oldfd, __const char *__old, int __newfd,
__const char *__new) __attribute__ ((__nothrow__));

extern FILE *tmpfile (void) ;
# 206 "/usr/include/stdio.h" 3 4
extern char *tmpnam (char *__s) __attribute__ ((__nothrow__)) ;

extern char *tmpnam_r (char *__s) __attribute__ ((__nothrow__)) ;
# 224 "/usr/include/stdio.h" 3 4
extern char *tempnam (__const char *__dir, __const char *__pfx)
__attribute__ ((__nothrow__)) __attribute__ ((__malloc__)) ;

extern int fclose (FILE *__stream);

extern int fflush (FILE *__stream);

# 249 "/usr/include/stdio.h" 3 4
extern int fflush_unlocked (FILE *__stream);
# 263 "/usr/include/stdio.h" 3 4

extern FILE *fopen (__const char *__restrict __filename,
__const char *__restrict __modes) ;

extern FILE *freopen (__const char *__restrict __filename,
__const char *__restrict __modes,
FILE *__restrict __stream) ;
# 292 "/usr/include/stdio.h" 3 4

# 303 "/usr/include/stdio.h" 3 4
extern FILE *fdopen (int __fd, __const char *__modes) __attribute__ ((__nothrow__)) ;
# 316 "/usr/include/stdio.h" 3 4
extern FILE *fmemopen (void *__s, size_t __len, __const char *__modes)
__attribute__ ((__nothrow__)) ;

extern FILE *open_memstream (char **__bufloc, size_t *__sizeloc) __attribute__ ((__nothrow__)) ;

extern void setbuf (FILE *__restrict __stream, char *__restrict __buf) __attribute__ ((__nothrow__));

extern int setvbuf (FILE *__restrict __stream, char *__restrict __buf,
int __modes, size_t __n) __attribute__ ((__nothrow__));

extern void setbuffer (FILE *__restrict __stream, char *__restrict __buf,
size_t __size) __attribute__ ((__nothrow__));

extern void setlinebuf (FILE *__stream) __attribute__ ((__nothrow__));

extern int fprintf (FILE *__restrict __stream,
__const char *__restrict __format, ...);

extern int printf (__const char *__restrict __format, ...);

extern int sprintf (char *__restrict __s,
__const char *__restrict __format, ...) __attribute__ ((__nothrow__));

extern int vfprintf (FILE *__restrict __s, __const char *__restrict __format,
__gnuc_va_list __arg);

extern int vprintf (__const char *__restrict __format, __gnuc_va_list __arg);

extern int vsprintf (char *__restrict __s, __const char *__restrict __format,
__gnuc_va_list __arg) __attribute__ ((__nothrow__));

extern int snprintf (char *__restrict __s, size_t __maxlen,
__const char *__restrict __format, ...)
__attribute__ ((__nothrow__)) __attribute__ ((__format__ (__printf__, 3, 4)));

extern int vsnprintf (char *__restrict __s, size_t __maxlen,
__const char *__restrict __format, __gnuc_va_list __arg)
__attribute__ ((__nothrow__)) __attribute__ ((__format__ (__printf__, 3, 0)));

# 414 "/usr/include/stdio.h" 3 4
extern int vdprintf (int __fd, __const char *__restrict __fmt,
__gnuc_va_list __arg)
__attribute__ ((__format__ (__printf__, 2, 0)));
extern int dprintf (int __fd, __const char *__restrict __fmt, ...)
__attribute__ ((__format__ (__printf__, 2, 3)));

extern int fscanf (FILE *__restrict __stream,
__const char *__restrict __format, ...) ;

extern int scanf (__const char *__restrict __format, ...) ;

extern int sscanf (__const char *__restrict __s,
__const char *__restrict __format, ...) __attribute__ ((__nothrow__));
# 445 "/usr/include/stdio.h" 3 4
extern int fscanf (FILE *__restrict __stream, __const char *__restrict __format, ...) __asm__ ("" "__isoc99_fscanf")

;
extern int scanf (__const char *__restrict __format, ...) __asm__ ("" "__isoc99_scanf")
;
extern int sscanf (__const char *__restrict __s, __const char *__restrict __format, ...) __asm__ ("" "__isoc99_sscanf") __attribute__ ((__nothrow__))

;
# 465 "/usr/include/stdio.h" 3 4

extern int vfscanf (FILE *__restrict __s, __const char *__restrict __format,
__gnuc_va_list __arg)
__attribute__ ((__format__ (__scanf__, 2, 0))) ;

extern int vscanf (__const char *__restrict __format, __gnuc_va_list __arg)
__attribute__ ((__format__ (__scanf__, 1, 0))) ;

extern int vsscanf (__const char *__restrict __s,
__const char *__restrict __format, __gnuc_va_list __arg)
__attribute__ ((__nothrow__)) __attribute__ ((__format__ (__scanf__, 2, 0)));
# 496 "/usr/include/stdio.h" 3 4
extern int vfscanf (FILE *__restrict __s, __const char *__restrict __format, __gnuc_va_list __arg) __asm__ ("" "__isoc99_vfscanf")

__attribute__ ((__format__ (__scanf__, 2, 0))) ;
extern int vscanf (__const char *__restrict __format, __gnuc_va_list __arg) __asm__ ("" "__isoc99_vscanf")

__attribute__ ((__format__ (__scanf__, 1, 0))) ;
extern int vsscanf (__const char *__restrict __s, __const char *__restrict __format, __gnuc_va_list __arg) __asm__ ("" "__isoc99_vsscanf") __attribute__ ((__nothrow__))

__attribute__ ((__format__ (__scanf__, 2, 0)));
# 524 "/usr/include/stdio.h" 3 4

extern int fgetc (FILE *__stream);
extern int getc (FILE *__stream);

extern int getchar (void);

# 552 "/usr/include/stdio.h" 3 4
extern int getc_unlocked (FILE *__stream);
extern int getchar_unlocked (void);
# 563 "/usr/include/stdio.h" 3 4
extern int fgetc_unlocked (FILE *__stream);

extern int fputc (int __c, FILE *__stream);
extern int putc (int __c, FILE *__stream);

extern int putchar (int __c);

# 596 "/usr/include/stdio.h" 3 4
extern int fputc_unlocked (int __c, FILE *__stream);

extern int putc_unlocked (int __c, FILE *__stream);
extern int putchar_unlocked (int __c);

extern int getw (FILE *__stream);

extern int putw (int __w, FILE *__stream);

extern char *fgets (char *__restrict __s, int __n, FILE *__restrict __stream)
;

extern char *gets (char *__s) ;

# 658 "/usr/include/stdio.h" 3 4
extern __ssize_t __getdelim (char **__restrict __lineptr,
size_t *__restrict __n, int __delimiter,
FILE *__restrict __stream) ;
extern __ssize_t getdelim (char **__restrict __lineptr,
size_t *__restrict __n, int __delimiter,
FILE *__restrict __stream) ;

extern __ssize_t getline (char **__restrict __lineptr,
size_t *__restrict __n,
FILE *__restrict __stream) ;

extern int fputs (__const char *__restrict __s, FILE *__restrict __stream);

extern int puts (__const char *__s);

extern int ungetc (int __c, FILE *__stream);

extern size_t fread (void *__restrict __ptr, size_t __size,
size_t __n, FILE *__restrict __stream) ;

extern size_t fwrite (__const void *__restrict __ptr, size_t __size,
size_t __n, FILE *__restrict __s);

# 730 "/usr/include/stdio.h" 3 4
extern size_t fread_unlocked (void *__restrict __ptr, size_t __size,
size_t __n, FILE *__restrict __stream) ;
extern size_t fwrite_unlocked (__const void *__restrict __ptr, size_t __size,
size_t __n, FILE *__restrict __stream);

extern int fseek (FILE *__stream, long int __off, int __whence);

extern long int ftell (FILE *__stream) ;

extern void rewind (FILE *__stream);

# 766 "/usr/include/stdio.h" 3 4
extern int fseeko (FILE *__stream, __off_t __off, int __whence);

extern __off_t ftello (FILE *__stream) ;
# 785 "/usr/include/stdio.h" 3 4

extern int fgetpos (FILE *__restrict __stream, fpos_t *__restrict __pos);

extern int fsetpos (FILE *__stream, __const fpos_t *__pos);
# 808 "/usr/include/stdio.h" 3 4

# 817 "/usr/include/stdio.h" 3 4

extern void clearerr (FILE *__stream) __attribute__ ((__nothrow__));

extern int feof (FILE *__stream) __attribute__ ((__nothrow__)) ;

extern int ferror (FILE *__stream) __attribute__ ((__nothrow__)) ;

extern void clearerr_unlocked (FILE *__stream) __attribute__ ((__nothrow__));
extern int feof_unlocked (FILE *__stream) __attribute__ ((__nothrow__)) ;
extern int ferror_unlocked (FILE *__stream) __attribute__ ((__nothrow__)) ;

extern void perror (__const char *__s);

# 1 "/usr/include/i386-linux-gnu/bits/sys_errlist.h" 1 3 4
# 27 "/usr/include/i386-linux-gnu/bits/sys_errlist.h" 3 4
extern int sys_nerr;
extern __const char *__const sys_errlist[];
# 847 "/usr/include/stdio.h" 2 3 4

extern int fileno (FILE *__stream) __attribute__ ((__nothrow__)) ;

extern int fileno_unlocked (FILE *__stream) __attribute__ ((__nothrow__)) ;
# 866 "/usr/include/stdio.h" 3 4
extern FILE *popen (__const char *__command, __const char *__modes) ;

extern int pclose (FILE *__stream);

extern char *ctermid (char *__s) __attribute__ ((__nothrow__));
# 906 "/usr/include/stdio.h" 3 4
extern void flockfile (FILE *__stream) __attribute__ ((__nothrow__));

extern int ftrylockfile (FILE *__stream) __attribute__ ((__nothrow__)) ;

extern void funlockfile (FILE *__stream) __attribute__ ((__nothrow__));
# 936 "/usr/include/stdio.h" 3 4

# 2 "main.c" 2

int main(void)
{
printf("hello world\n");
return 0;
}

.file	"main.c"
.section	.rodata
.LC0:
.string	"hello world"
.text
.globl	main
.type	main, @function
main:
.LFB0:
.cfi_startproc
pushl	%ebp
.cfi_def_cfa_offset 8
.cfi_offset 5, -8
movl	%esp, %ebp
.cfi_def_cfa_register 5
andl	$-16, %esp
subl	$16, %esp
movl	$.LC0, (%esp)
call	puts
movl	$0, %eax
leave
.cfi_restore 5
.cfi_def_cfa 4, 4
ret
.cfi_endproc
.LFE0:
.size	main, .-main
.ident	"GCC: (Ubuntu/Linaro 4.6.1-9ubuntu3) 4.6.1"
.section	.note.GNU-stack,"",@progbits