837273 - Add a control symbol to validate symbolication

Status: RESOLVED WONTFIX

(Core :: Gecko Profiler, task, P3)

Description

[Benoit Girard (:BenWa)]

I often see profiles where the symbolication failed. This can happen for many reasons:
1) We get the wrong shared library offsets
2) We mismatch the library we run and the source of our symbols
3) Perhaps we're running with the wrong addr2line like utility

If we included an address for a fixed symbol we can validate that this address resolve to say XRE_main and warn the user that the symbolication is invalid.

The proper way to do that is to use the library signature but this difficult to do in a portable way.

Comment 1

[Gerald Squelart (he/him) (not at Mozilla since 2022-09-15)]

This still sounds like a good idea.
Markus, what do you think? (I'm re-triaging bugs.)

Comment 2

[Markus Stange [:mstange]]

Fun idea, but it doesn't seem necessary these days. 1 is not an issue, 2 is almost never an issue (see bug 773890 comment 7), 3 is not an issue. The only real issue is that we sometimes fall back to getting symbols from a stripped binary. For that issue, https://github.com/mstange/profiler-get-symbols/issues/23 is the better way forward.