2033336 - Code coverage has stopped recording files in UNIFIED_SOURCES

Status: RESOLVED FIXED

(Firefox Build System :: General, defect)

Description

[Geoff Lankow (:darktrojan)]

No code coverage data has been recorded after 2026-04-16 for many .cpp files (e.g. the coverage graph for Preferences.cpp stops before the end). It seems that files outside of unified builds are not affected (e.g. deflate.c has more recent data), so I think it's very likely caused by bug 2031965.

Comment 1

[BugBot [:suhaib / :marco]]

:emilio, since you are the author of the regressor, bug 2031965, could you take a look? Also, could you set the severity field?

For more information, please visit BugBot documentation.

Comment 2

[Emilio Cobos Álvarez [:emilio]]

I'm not familiar with our code coverage instrumentation. Do you know how we map it to the source tree? It seems believable but I don't know where to start looking :)

Comment 3

[BugBot [:suhaib / :marco]]

Set release status flags based on info from the regressing bug 2031965

Comment 4

[Marco Castelluccio [:marco]]

There are a couple of places in https://searchfox.org/firefox-main/source/testing/mozharness/mozharness/mozilla/testing/codecoverage.py that might need to be updated (see everything related to prefix, there's both an option passed to grcov and also GCOV_PREFIX and GCOV_PREFIX_STRIP).

I also see other files in the tree that set GCOV_PREFIX.

Unfortunately it's a bit brittle... So you'd have to do a few attemps with try pushes.

Comment 5

[BugBot [:suhaib / :marco]]

The severity field is not set for this bug.
:ahochheiden, could you have a look please?

For more information, please visit BugBot documentation.

Comment 6

[Nicolas Guichard]

Attachment: Bug 2033336 - Update grcov to v0.10.8. r?marco!

This new grcov release includes a bugfix for GCNOs pointing to C++
files outside the objdir with relative paths, as we typically get when
building with unified sources.

See https://github.com/mozilla/grcov/pull/1519 for details.

Comment 7

[Pulsebot]

Pushed by [e-mail]:
https://github.com/mozilla-firefox/firefox/commit/08f3e323f0e0
https://hg.mozilla.org/integration/autoland/rev/4cd6e8d4c669
Update grcov to v0.10.8. r=marco

Comment 8

[Sandor Molnar[:smolnar]]

https://hg.mozilla.org/mozilla-central/rev/4cd6e8d4c669