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GDB & LLDB debug commands

A short cheatsheet for debugging.

Original source: https://developer.apple.com/library/archive/documentation/IDEs/Conceptual/gdb_to_lldb_transition_guide/document/lldb-command-examples.html

Execution commands

Aliases and short forms separated by /

Task GDB LLDB
Launch a process without any argument (gdb) run / (lldb) process launch / run / r
Launch a process with arguments (gdb) run <args> / r <args> (lldb) process launch -- <args> / r <args>
Launch process a.out with arguments 1 2 3 without supplying them (defaults) $ gdb --args a.out 1 2 3 $ lldb -- a.out 1 2 3
Set env. variables before launching (gdb) set env VAR VALUE (lldb) settings set target.env-vars VAR=VALUE / set se ...
Attach to the process with PID 123 (gdb) attach 123 (lldb) process attach --pid 123 / attach -p 123
Attach to a process named a.out (gdb) attach a.out (lldb) process attach --name a.out / pro at -n a.out
Wait for a process named a.out to launch and attach (gdb) attach -waitfor a.out (lldb) process attach --name a.out --waitfor / pro at -n a.out -w
Attach to a remote GDB protocol server (gdb) target remote domain:port (lldb) gdb-remote domain:port
Attach to a local GDB protocol server (gdb) target remote localhost:port (lldb) gdb-remote port
Source-based single step in the currently selected thread (gdb) step / s (lldb) thread step-in / step / s
Source-based single step over the currently selected thread (gdb) next / n (lldb) thread step-over / next / n
Instruction-based single step in the currently selected thread (gdb) stepi / si (lldb) thread step-inst / si
Instruction-based single step over the currently selected thread (gdb) nexti / ni (lldb) thread step-inst-over / ni
Step out of the currently selected frame (gdb) finish (lldb) thread step-out / finish

Breakpoint commands

Task GDB LLDB
Set a breakpoint in all functions named main (gdb) break main (lldb) breakpoint set --name main / br s -n main / b main
Set a breakpoint in file test.c at line 12 (gdb) break test.c:12 (lldb) breakpoint set --file test.c --line 12 / br s -f test.c -l 12 / b test.c:12
Set a breakpoint at all C++ methods whose basename is main. (gdb) break main (lldb) breakpoint set --method main / br s -M main
Set a breakpoint at an Objective-C function: -[NSString stringWithFormat:] (gdb) break -[NSString stringWithFormat:] (lldb) breakpoint set --name "-[NSString stringWithFormat:]" / b -[NSString stringWithFormat:]
Set a breakpoint at all Objective-C methods whose selector is count (gdb) break count (lldb) breakpoint set --selector count / br s -S count
Set a breakpoint by a regex on a function name (gdb) rbreak regular-expression (lldb) breakpoint set --regex regular-expression / br s -r regular-expression
Set a breakpoint by a regular expression on a source file’s content (gdb) shell grep -e -n pattern source-file / break source-file:CopyLineNumbers (lldb) breakpoint set --source-pattern regular-expression --file SourceFile / br s -p regular-expression -f file
List all breakpoints (gdb) info break (lldb) breakpoint list / br l
Delete a breakpoint (gdb) delete 1 (lldb) breakpoint delete 1 / br del 1

Watchpoint Commands

TODO

Examining variables

TODO

Evaluating Expressions

TODO

Examining Thread State

TODO

Executable and Shared Library Query Commands

TODO

Misc.

TODO