[FFe] Rebuild log4cplus with correct symbols visibility

[Athos Ribeiro]

As part of the log4cplus MIR work (LP: #2003549), we are adding DEP8 tests and a symbols file for liblog4cplus.

While those changes should not need a FFe, we are also including a "-fvisibility=hidden" build flag, since the source code is annotated to only export the symbols the developers want to be publicly exposed.

As a result several symbols (which were leaking, belonging to other libraries) are no longer being exposed. Since this is a change in the shared library binaries, we decided it would be better to file an FFe.

Note that the new exported symbols list is the intended one for linux systems: the upstream project claims that autotools is the preferred build system for unix-like systems, and the proposed symbols file is what we get from default autotools based builds. However, the package currently builds with cmake, where the "-fvisibility=hidden" flag was missing.

We have ran test rebuilds of the reverse dependencies (isc-kea and openvdb) and also verified (best effort) that the versions of such reverse dependencies in the archive are still functional after the changes.

The changes in question and further discussions are available at https://code.launchpad.net/~athos-ribeiro/ubuntu/+source/log4cplus/+git/log4cplus/+merge/437047.

A PPA with the proposed package and the rdeps test rebuilds is available at https://launchpad.net/~athos-ribeiro/+archive/ubuntu/log4cplus-symbols/+packages.

This Is the proposed chagelog diff:

diff --git a/debian/changelog b/debian/changelog
index 3177ffb..10c0af2 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,14 @@
+log4cplus (2.0.8-1ubuntu1) lunar; urgency=medium
+
+ * d/rules: set the default symbol visibility to hidden.
+ * d/liblog4cplus-2.0.5.symbols*: add symbols files.
+ * Apply filters to exported symbols.
+ * d/liblog4cplus-2.0.5.lintian-overrides: remove lintian overrides for
+ missing symbols file.
+ * d/tests: use upstream examples as DEP8 tests.
+
+ -- Athos Ribeiro <email address hidden> Tue, 07 Feb 2023 08:43:44 -0300
+
 log4cplus (2.0.8-1) unstable; urgency=medium

   * New upstream version 2.0.8

[Graham Inggs (ginggs)]

I noticed isc-kea FTBFS on !amd64 due to missing symbols. Do you plan to upload isc-kea as well?

[Athos Ribeiro (athos-ribeiro)]

Hi Graham,

Thanks for looking into this one.

The kea build on that PPA is failing due to kea's own symbols file experiments I am running in that PPA. This is not the same isc-kea package we have in the archive (symbols file was added to this one).

I am using the same PPA becaue that one has riscv enable. Sorry for not communicating that here.

The isc-kea builds prepared for this FFe and for the log4cplus MP were the ones for isc-kea 2.2.0-3ubuntu1.1~ppa2, as shown in https://launchpad.net/~athos-ribeiro/+archive/ubuntu/log4cplus-symbols/+builds?build_text=isc-kea&build_state=built

[Graham Inggs (ginggs)]

Understood, but do you intend to upload isc-kea with a symbols file added?

[Athos Ribeiro (athos-ribeiro)]

Yes, we do. This is part of the MIR efforts for kea.

We are preparing the symbols file for isc-kea now.

However, in the isc-kea case, we are not going to apply any filters, i.e., we will not change the current exported symbols. Therefore, we will not file a FFe for that, AFAICT. If this changes (in case we do decide a version script is needed there as well), we will file another FFe for isc-kea.

[Graham Inggs (ginggs)]

OK, thanks. I just wanted to be clear whether the upload of isc-kea was part of this FFe.
FFe granted, please go ahead.

[Athos Ribeiro (athos-ribeiro)]

Thanks! Uploaded

[Launchpad Janitor (janitor)]

This bug was fixed in the package log4cplus - 2.0.8-1ubuntu1

---------------
log4cplus (2.0.8-1ubuntu1) lunar; urgency=medium

  * d/rules: set the default symbol visibility to hidden. (LP: #2008730)
  * d/liblog4cplus-2.0.5.symbols*: add symbols files.
  * Apply filters to exported symbols.
  * d/liblog4cplus-2.0.5.lintian-overrides: remove lintian overrides for
    missing symbols file.
  * d/tests: use upstream examples as DEP8 tests.

 -- Athos Ribeiro <email address hidden> Tue, 07 Feb 2023 08:43:44 -0300