LLDB (Low Level Debugger)

LLDB is a debugger for LLVM/Clang compiler, normally used in MacOS

LLDB Cheat Sheet

A complete gdb to lldb command map.

Print out

• Print object

(lldb) po responseObject
(lldb) po [responseObject objectForKey@"state"]

• p - Print primitive type

Breakpoints

• List breakpoints

br l

• br delete - Delete breakpoint

(lldb) br delete 1

• br e - Enable breakpoint
• br di - Disable breakpoint
• b - Add breakpoint

(lldb) b MyViewController.m:30

• br set - Add symbolic breakpoint

(lldb) br set -n viewDidLoad

• Conditional break

for(PlayerItem *item in player.inventory) {
    totalValue += item.value;
}

Set a conditional breakpoint that triggers only when totalValue is greater than 1000:

(lldb) b MerchantViewController.m:32
Breakpoint 3: where = lootcollector`-[MerchantViewController] ...
(lldb) br mod -c "totalValue > 1000" 3

Reset the condition:

(lldb) br mod -c "" 3

• Run a debugger command from a breakpoint

(lldb) br com add 2
Enter your debugger command(s). Type 'DONE' to end.
> bt
> continue
> DONE

• Resume excution

(lldb) continue

• Step over

(lldb) n

• Step in

(lldb) s

• Print backtrace

(lldb) bt