(gdb) disass jmpesp
Dump of assembler code for function jmpesp:
   0x080483d4 <+0>:	push   ebp
   0x080483d5 <+1>:	mov    ebp,esp
   0x080483d7 <+3>:	jmp    esp
   0x080483d9 <+5>:	pop    ebp
   0x080483da <+6>:	ret
End of assembler dump.