Notes for gcc-13 - reproducible builds result

Version annotated: 13-20230320-1
Identified issues:
Identifier: blacklisted_on_jenkins
Description Some packages have been blacklisted in our test infrastructure because
their build hangs, takes too long, spawns processes that are not killed, or
simply because they use too many resources for our current capacity. (This
is purely practical step - we would like to test these packages.)
Identifier: test_suite_logs
Description Package embeds test suite logs, which may include a variety of
issues such as timestamps, timing information, kernel, username,
hostname, etc.
Identifier: diffoscope_runs_forever
URL https://reproducible.debian.net/index_breakages.html
Description Some packages cannot be analysed by diffoscope due to it running "forever".
Currently the diffoscope process is killed after 120 minutes.
https://reproducible.debian.net/index_breakages.html collects a list of currently
undiffable packages (as well as other issues with tests.reproducile-builds.org.
Comments: @DATE@ embedded in libstdc++-v3/doc/doxygen/mainpage.html by way
of the run_doxygen script
https://gcc.gnu.org/git?p=gcc.git;a=blob;f=libstdc%2B%2B-v3/scripts/run_doxygen;h=42ed9eb4f5dfa8ed7697f4ac50353133ff6a8e6b;hb=cc035c5d8672f87dc8c2756d9f8367903aa72d93#l133
.
Includes build log containing timestamp and other
non-deterministic information in _formulas.log in documentation
directories.
.
Disabling Profile Guided Optimization (PGO) and Link-Time
Optimization (LTO) with DEB_BUILD_OPTIONS="nolto nopgo"
significantly reduce reproducibility issues.
.
Building with DEB_BUILD_OPTIONS="nocheck" fixes the test_suite_log
issues.
.
Building with DEB_BUILD_OPTIONS="nodoc" avoids some
non-determinism in the documentation.
.
Currently enabling several DEB_BUILD_OPTIONS in test infrastructure
https://salsa.debian.org/qa/jenkins.debian.net/-/blob/7a6b2e0235dd62b86886c5d46e7b7c53ea5779c1/bin/reproducible_build.sh#L613
 

Our notes about issues affecting packages are stored in notes.git and are targeted at packages in Debian in 'unstable/amd64' (unless they say otherwise).