Various helpfull gdb commands.

I recommand using my own config file which integrates gdb-dashboard which is vastly superior to the default gdb -tui mode. Furthermore, I added autoload of the rust python pretty print module and add the rust stdlib if source is present (install via rustup component add rust-src).

I recommand using rr since it allows for faster recording than native gdb (~2times slowdown vs ~50ktimes). This is especially usefull when you want to use reverse direction.

# setup breakpoint when panic is invoked
b rust_panic
b rust_begin_unwind
# alternative breakpoint for panic
b std::panicking::rust_panic_with_hook
# print value of element of vec (which is a Vec)
p vec.buf.ptr.pointer.__0[0]

• backtrace ('ba') full -- Complete backtrace with local variables
• up, down, frame -- Move through frames
• watch -- Suspend the process when a certain condition is met
• set print pretty on -- Prints out prettily formatted C source code
• set logging on -- Log debugging session to show to others for support
• set print array on -- Pretty array printing
• finish -- Continue till end of function
• enable and disable -- Enable/disable breakpoints
• tbreak -- Break once, and then remove the breakpoint
• where -- Line number currently being executed
• info locals -- View all local variables
• info args -- View all function arguments
• rbreak -- Break on function matching regular expression
• print -- Print value of expression
• whatis -- Print data type of expression
• record -- Record a log of the process execution to replay it later
• (more info)

• talk on the subject
• example with watchpoint
• reverse-continue ('rc') -- Continue program being debugged but run it in reverse
• reverse-finish -- Execute backward until just before the selected stack frame is called
• reverse-next ('rn') -- Step program backward, proceeding through subroutine calls.
• reverse-nexti ('rni') -- Step backward one instruction, but proceed through called subroutines.
• reverse-step ('rs') -- Step program backward until it reaches the beginning of a previous source line
• reverse-stepi -- Step backward exactly one instruction
• set exec-direction (forward/reverse) -- Set direction of execution.
• more info

• p/d 0x10 -- gives decimal equivalent of 0x10
• p/t 0x10 -- binary equivalent of 0x10
• p/x 256 -- hex equivalent of 256