#1136320 qtltools: FTBFS with libeigen3-dev 5.0 (major version transition)

#1136320#5
Date:
2026-05-11 20:41:21 UTC
From:
To:
Dear Maintainer,

your package depends on libeigen3-dev. The upstream released a
new major version of this mathematical library, 5.0.0. Some
basic information about new features and changes in this version
can be found here:

https://libeigen.gitlab.io/releases/5.0/

This is a major version change and may require code changes in packages
depending on eigen3. The key breaking changes include:

  - Minimum required C++ standard is now C++14
  - Changes in the build system integration
  - Some API name changes

qtltools FTBFS with libeigen3-dev 5.0.1. The full build log is available at:

https://debusine.debian.net/debian/developers-gladk-eigen3/artifact/3761106/raw/qtltools_1.3.1+dfsg-4_amd64-2026-05-08T16:04:53Z.build

Here is the most probably relevant part of the failing build log:
    ===========================================

g++ -std=c++0x -o obj/data.o -c src/common/data.cpp -O3 -Wall -Wextra -Wno-sign-compare -Wno-unused-local-typedefs -Wno-deprecated -Wno-unused-parameter -g -O2 -ffile-prefix-map=/build/reproducible-path/qtltools-1.3.1+dfsg=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wdate-time -D_FORTIFY_SOURCE=2 -I/usr/include/eigen3 -Ilib/OTools -Ilib
g++ -std=c++0x -o obj/ase_main.o -c src/mode_ase/ase_main.cpp -O3 -Wall -Wextra -Wno-sign-compare -Wno-unused-local-typedefs -Wno-deprecated -Wno-unused-parameter -g -O2 -ffile-prefix-map=/build/reproducible-path/qtltools-1.3.1+dfsg=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wdate-time -D_FORTIFY_SOURCE=2 -I/usr/include/eigen3 -Ilib/OTools -Ilib
g++ -std=c++0x -o obj/ase_management.o -c src/mode_ase/ase_management.cpp -O3 -Wall -Wextra -Wno-sign-compare -Wno-unused-local-typedefs -Wno-deprecated -Wno-unused-parameter -g -O2 -ffile-prefix-map=/build/reproducible-path/qtltools-1.3.1+dfsg=. -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -Wdate-time -D_FORTIFY_SOURCE=2 -I/usr/include/eigen3 -Ilib/OTools -Ilib
In file included from /usr/include/eigen3/Eigen/Core:22,
                 from /usr/include/eigen3/Eigen/Dense:1,
                 from lib/OTools/residualizer.h:36,
                 from lib/OTools/otools.h:60,
                 from src/mode_ase/../common/data.h:19,
                 from src/mode_ase/ase_data.h:20,
                 from src/mode_ase/ase_management.cpp:16:
/usr/include/eigen3/Eigen/src/Core/util/Macros.h:749:2: error: #error Eigen requires at least c++14 support.
  749 | #error Eigen requires at least c++14 support.
      |  ^~~~~
In file included from /usr/include/eigen3/Eigen/Core:22,
                 from /usr/include/eigen3/Eigen/Dense:1,
                 from lib/OTools/residualizer.h:36,
                 from lib/OTools/otools.h:60,
                 from src/common/data.h:19,
                 from src/common/data.cpp:16:
/usr/include/eigen3/Eigen/src/Core/util/Macros.h:749:2: error: #error Eigen requires at least c++14 support.
  749 | #error Eigen requires at least c++14 support.
      |  ^~~~~
In file included from /usr/include/eigen3/Eigen/Core:22,
                 from /usr/include/eigen3/Eigen/Dense:1,
                 from lib/OTools/residualizer.h:36,
                 from lib/OTools/otools.h:60,
                 from src/mode_ase/../common/data.h:19,
                 from src/mode_ase/ase_data.h:20,
                 from src/mode_ase/ase_main.cpp:16:
/usr/include/eigen3/Eigen/src/Core/util/Macros.h:749:2: error: #error Eigen requires at least c++14 support.
  749 | #error Eigen requires at least c++14 support.
      |  ^~~~~
In file included from /usr/include/eigen3/Eigen/Core:22,
                 from /usr/include/eigen3/Eigen/Dense:1,
                 from lib/OTools/residualizer.h:36,
                 from lib/OTools/otools.h:60,
                 from src/mode_cis/../common/data.h:19,
                 from src/mode_cis/cis_data.h:33,
                 from src/QTLtools.cpp:16:

    ===========================================
libeigen3-dev_5.0.1-1 is available in experimental.

When this package version lands into unstable (probably at the beginning
of June 2026), this bug will be increased in severity to serious.

Thanks,

Anton