GDB Cheatsheet

一些開發 OS 時常用到的指令，意外解出很多奇妙 bug

Display variable

• Display variable name hello

  • display hello

• Display with different format: (ref: Output formats)

  • display/x (hex)
  • display/t (binary)

Examining Memory

General format: x/nfu addr, n(count), f(format), u(unit size)

• Examining memory start from 0x720 with 20 items in hex with 8 bits in each item
  • x/20b 0x720 or x/20xb 0x720 becuase format is default to hex
• Set breakpoint while pc=0x8000
  • break *0x8000 (* is necessary)

Show register

• info registers

Set variable

Set a variable with name myVar1

• set $myVar1 = 1