Bug#1097177: libdate-pcalc-perl: ftbfs with GCC-15

[Matthias Klose]

Package: src:libdate-pcalc-perl
Version: 6.1-7
Severity: important
Tags: sid forky
User: debian-gcc at lists.debian.org
Usertags: ftbfs-gcc-15

[This bug is NOT targeted to the upcoming trixie release]

Please keep this issue open in the bug tracker for the package it
was filed for.  If a fix in another package is required, please
file a bug for the other package (or clone), and add a block in this
package. Please keep the issue open until the package can be built in
a follow-up test rebuild.

The package fails to build in a test rebuild on at least amd64 with
gcc-15/g++-15, but succeeds to build with gcc-14/g++-14. The
severity of this report will be raised before the forky release.

The full build log can be found at:
http://qa-logs.debian.net/2025/02/16/amd64exp/libdate-pcalc-perl_6.1-7_unstable_gccexp.log.gz
The last lines of the build log are at the end of this report.

To build with GCC 15, either set CC=gcc-15 CXX=g++-15 explicitly,
or install the gcc, g++, gfortran, ... packages from experimental.

  apt-get -t=experimental install g++ 

GCC 15 now defaults to the C23/C++23 standards, exposing many FTBFS.
Other Common build failures are new warnings resulting in build failures
with -Werror turned on, or new/dropped symbols in Debian symbols files.
For other C/C++ related build failures see the porting guide at
http://gcc.gnu.org/gcc-15/porting_to.html

[...]
USER=user42

dpkg-buildpackage
-----------------

Command: dpkg-buildpackage --sanitize-env -us -uc -b
dpkg-buildpackage: info: source package libdate-pcalc-perl
dpkg-buildpackage: info: source version 6.1-7
dpkg-buildpackage: info: source distribution unstable
dpkg-buildpackage: info: source changed by Jelmer Vernooij <jelmer at debian.org>
 dpkg-source --before-build .
dpkg-buildpackage: info: host architecture amd64
 debian/rules clean
dh clean
   dh_clean
 debian/rules binary
dh binary
   dh_update_autotools_config
   dh_autoreconf
   dh_auto_configure
	/usr/bin/perl Makefile.PL INSTALLDIRS=vendor "OPTIMIZE=-g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/libdate-pcalc-perl-6.1=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wdate-time -D_FORTIFY_SOURCE=2" "LD=x86_64-linux-gnu-gcc -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/libdate-pcalc-perl-6.1=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wl,-z,relro -Wl,-z,now"
Testing your C compiler...

Config.pm indicates that your version of Perl was built with
this C compiler:

    x86_64-linux-gnu-gcc

I have located and successfully tested this compiler on your system.

You now have the option to either install the (fast) C/XS implementation of
this module (recommended), or a (somewhat slower) pure-Perl implementation.

Install C/XS version (answer 'c') or pure-Perl version (answer 'p')? [c] c
Checking if your kit is complete...
Looks good
Generating a Unix-style Makefile
Writing Makefile for Date::Pcalc
Writing MYMETA.yml and MYMETA.json
Writing patchlevel.h for /usr/bin/perl (5.040000)
   dh_auto_build
	make -j8
make[1]: Entering directory '/build/reproducible-path/libdate-pcalc-perl-6.1'
Running Mkbootstrap for Pcalc ()
x86_64-linux-gnu-gcc -c   -D_REENTRANT -D_GNU_SOURCE -DDEBIAN -fwrapv -fno-strict-aliasing -pipe -I/usr/local/include -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -g -O2 -Werror=implicit-function-declaration -ffile-prefix-map=/build/reproducible-path/libdate-pcalc-perl-6.1=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wdate-time -D_FORTIFY_SOURCE=2   -DVERSION=\"6.1\" -DXS_VERSION=\"6.1\" -fPIC "-I/usr/lib/x86_64-linux-gnu/perl/5.40/CORE"   DatePcalc.c
"/usr/bin/perl" "/usr/share/perl/5.40/ExtUtils/xsubpp"  -typemap '/usr/share/perl/5.40/ExtUtils/typemap' -typemap '/build/reproducible-path/libdate-pcalc-perl-6.1/typemap'  Pcalc.xs > Pcalc.xsc
chmod 644 "Pcalc.bs"
"/usr/bin/perl" -MExtUtils::Command::MM -e 'cp_nonempty' -- Pcalc.bs blib/arch/auto/Date/Pcalc/Pcalc.bs 644
cp lib/Date/Pcalendar/Year.pm blib/lib/Date/Pcalendar/Year.pm
cp lib/Date/Pcalendar/Profiles.pm blib/lib/Date/Pcalendar/Profiles.pm
cp lib/Date/Pcalendar/Profiles.pod blib/lib/Date/Pcalendar/Profiles.pod
cp Pcalc.pod blib/lib/Date/Pcalc.pod
cp lib/Date/Pcalc/Object.pod blib/lib/Date/Pcalc/Object.pod
cp Pcalc.pm blib/lib/Date/Pcalc.pm
cp Pcalendar.pm blib/lib/Date/Pcalendar.pm
cp Pcalendar.pod blib/lib/Date/Pcalendar.pod
cp lib/Date/Pcalendar/Year.pod blib/lib/Date/Pcalendar/Year.pod
cp lib/Date/Pcalc/Object.pm blib/lib/Date/Pcalc/Object.pm
In file included from DatePcalc.c:15:
ToolBox.h:98:17: error: cannot use keyword ‘false’ as enumeration constant
   98 |          enum { false, true };
      |                 ^~~~~
ToolBox.h:98:17: note: ‘false’ is a keyword with ‘-std=c23’ onwards
make[1]: *** [Makefile:350: DatePcalc.o] Error 1
make[1]: *** Waiting for unfinished jobs....
mv Pcalc.xsc Pcalc.c
make[1]: Leaving directory '/build/reproducible-path/libdate-pcalc-perl-6.1'
dh_auto_build: error: make -j8 returned exit code 2
make: *** [debian/rules:6: binary] Error 25
dpkg-buildpackage: error: debian/rules binary subprocess returned exit status 2