GDB Cheatsheet

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Text User interface

For a more interactive gdb session, can use a text user interface:

(gdb) layout src
(gdb) layout asm
(gdb) layout split

Depending on which command was run, it will display the source, assembler or both.

Altium Standards

To remove the text user interface (tui):

(gdb) tui disable

Commands

Stepping through code is done with the step command. Optionally a number of steps <N> can be specified. Entering a blank command after a step will continue stepping the code.

To only step 1 assembly instruction at a time, use stepi.

(gdb) step
(gdb) step <N>
(gdb) s
(gdb) stepi
(gdb) si

To step over (rather than into):

(gdb) next
(gdb) n

To step out of the current function:

(gdb) finish

Use continue to run to the next breakpoint.

(gdb) continue
(gdb) c

Use break to set a breakpoint at entry to <function>.

(gdb) break <function>
(gdb) b <function>

Set a breakpoint at a particular file on a particular line.

(gdb) break <file>:<ln>
(gdb) break main.rs:14

To disable and enable breakpoints, use the breakpoint numbers:

(gdb) disable 1
(gdb) enable 1

A value of a local variable can be printed with print. Expressions can also be evaluated

(gdb) print <a>
(gdb) p <a> 
(gdb) print <a + b>

To show the value of all local variables:

(gdb) info locals
(gdb) i locals

To show function args:

(gdb) info args

To set the value of a local:

(gdb) set <variable> = <value>

Reset the session:

(gdb) monitor reset halt

Show the current backtrace:

(gdb) backtrace

Ending a session

(gdb) quit

Remote debugging

(gdb) target remote <ipaddr>:<port>