1261180 - Add --debugger [gdb|lldb|rr|...] flag to marionette runner and mach

Status: NEW

(Testing :: Marionette Client and Harness, defect, P3)

Description

[Nick Fitzgerald [:fitzgen] [⏰PST; UTC-8]]

I am debugging an assertion failure where my only reproducible test case is running marionette tests and this is really annoying to debug with gdb because I have to try to find and attach to the process before it ends.

Would be a lot easier if I could add `--debugger gdb` when running marionette tests.

Comment 1

[Nick Fitzgerald [:fitzgen] [⏰PST; UTC-8]]

Specifically, a C++ assertion failure unrelated to the marionette tests, which results in crashing the process in DEBUG builds.

Comment 2

[(not currently active) Ted Mielczarek]

We've got a helpful mozdebug library in mozbase:
https://dxr.mozilla.org/mozilla-central/rev/494289c72ba3997183e7b5beaca3e0447ecaf96d/testing/mochitest/runtests.py#2213

Comment 3

[Henrik Skupin [:whimboo][⌚️UTC+2]]

Btw this is no only mach which is missing this flag. But also the runner doesn't have it yet.

Comment 4

[Andreas Tolfsen ❲:ato❳]

Unassigning myself.

Comment 7

[Brendan Dahl [:bdahl]]

For those looking for a temporary fix, I use a patch[1] that adds MOZ_DEBUG_PARENT_PROCESS (similar to MOZ_DEBUG_CHILD_PROCESS), where gecko dumps the process id and waits for a debugger to attach.


[1] https://github.com/brendandahl/gecko/commit/73f78b6b68ebd2520e893ad221c4a34bd2dd1045

Comment 8

[Vincent Hilla [:vhilla]]

A workaround for using rr is to rename the firefox binary and place a script in it's place

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
FIREFOX_BIN="${SCRIPT_DIR}/firefox-orig"

if [[ ! -x "$FIREFOX_BIN" ]]; then
  echo "Error: cannot find $FIREFOX_BIN" >&2
  exit 1
fi

exec rr record "$FIREFOX_BIN" "$@"