Hi,

nexus fails to build in a test rebuild on at least amd64 and arm64 with
gcc-16/g++-16, but builds properly with gcc-15/g++-15. The severity of this
report will be raised before the forky release.

The full build log can be found at:
https://people.debian.org/~ema/gcc-16-rebuilds/output-1/nexus_arm64.build.xz

The last lines of the build log are at the end of this report.

To build with GCC 16, either set CC=gcc-16 CXX=g++-16 explicitly,
or install the gcc, g++, gfortran, ... packages from experimental.

  apt-get -t=experimental install g++

Common build failures include unused (but set) variables, array subscripts
partly outside array bounds, and new/dropped symbols in Debian symbols files.
For other C/C++ related build failures see the porting guide at
http://gcc.gnu.org/gcc-16/porting_to.html

Please only close this issue after double-checking that the package can be
built correctly with GCC 16.

Please do not reassign this bug to another package. If a fix in another package
is required, then file a bug for the other package (or clone), and mark this
bug as blocked by the bug in the other package.

[...]


1 warning
cd /build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu/bindings/java && echo

make[3]: Leaving directory '/build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu'
Note: /build/reproducible-path/nexus-4.4.3/bindings/java/org/nexusformat/NexusFile.java uses unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.
1 warning
[ 36%] Built target NexusJavaBuild
[ 37%] Build Javadocs
cd /build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu/bindings/java && /usr/bin/javadoc -d /build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu/bindings/java/apidoc -windowtitle jnexus -doctitle jnexus -classpath . -Xdoclint:none -sourcepath /build/reproducible-path/nexus-4.4.3/bindings/java org.nexusformat ncsa.hdf.hdflib
make[3]: *** [applications/NXtranslate/FRM2/CMakeFiles/FRM2.dir/build.make:82: applications/NXtranslate/FRM2/CMakeFiles/FRM2.dir/frm2_retriever.cpp.o] Error 1
make[3]: Leaving directory '/build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu'
make[2]: *** [CMakeFiles/Makefile2:1626: applications/NXtranslate/FRM2/CMakeFiles/FRM2.dir/all] Error 2
Loading source files for package org.nexusformat...
Loading source files for package ncsa.hdf.hdflib...
Constructing Javadoc information...
make[3]: Leaving directory '/build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu'
make[2]: *** [CMakeFiles/Makefile2:1754: applications/NXtranslate/esrf_edf/CMakeFiles/Edf.dir/all] Error 2
Creating destination directory: "/build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu/bindings/java/apidoc/"
Building index for all the packages and classes...
Standard Doclet version 25.0.3-ea+5-Debian-2
Building tree for all the packages and classes...
Generating /build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu/bindings/java/apidoc/org/nexusformat/AttributeEntry.html...
Generating /build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu/bindings/java/apidoc/ncsa/hdf/hdflib/HDFArray.html...
Generating /build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu/bindings/java/apidoc/ncsa/hdf/hdflib/HDFConstants.html...
Generating /build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu/bindings/java/apidoc/ncsa/hdf/hdflib/HDFException.html...
make[3]: Leaving directory '/build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu'
make[2]: *** [CMakeFiles/Makefile2:1594: applications/NXtranslate/docs/CMakeFiles/SNShistogram.dir/all] Error 2
Generating /build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu/bindings/java/apidoc/ncsa/hdf/hdflib/HDFJavaException.html...
Generating /build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu/bindings/java/apidoc/ncsa/hdf/hdflib/HDFNativeData.html...
/build/reproducible-path/nexus-4.4.3/bindings/java/ncsa/hdf/hdflib/HDFNativeData.java:123: warning: unknown tag. Mistyped @return or an unregistered custom tag?
     *  @returns         an array of 'datasize' numbers of 'dataType
        ^
/build/reproducible-path/nexus-4.4.3/bindings/java/ncsa/hdf/hdflib/HDFNativeData.java:125: warning: reference not found: ncsa.hdf.hdfobject.HDFGR
     *  @see ncsa.hdf.hdfobject.HDFGR
        ^
/build/reproducible-path/nexus-4.4.3/bindings/java/ncsa/hdf/hdflib/HDFNativeData.java:126: warning: reference not found: ncsa.hdf.hdfobject.HDFSDS
     *  @see ncsa.hdf.hdfobject.HDFSDS
        ^
Generating /build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu/bindings/java/apidoc/ncsa/hdf/hdflib/HDFNotImplementedException.html...
Generating /build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu/bindings/java/apidoc/org/nexusformat/NexusException.html...
Generating /build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu/bindings/java/apidoc/org/nexusformat/NexusFile.html...
Generating /build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu/bindings/java/apidoc/org/nexusformat/NeXusFileInterface.html...
Generating /build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu/bindings/java/apidoc/org/nexusformat/NXlink.html...
Generating /build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu/bindings/java/apidoc/ncsa/hdf/hdflib/package-summary.html...
Generating /build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu/bindings/java/apidoc/ncsa/hdf/hdflib/package-tree.html...
Generating /build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu/bindings/java/apidoc/org/nexusformat/package-summary.html...
Generating /build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu/bindings/java/apidoc/org/nexusformat/package-tree.html...
Generating /build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu/bindings/java/apidoc/constant-values.html...
Generating /build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu/bindings/java/apidoc/serialized-form.html...
Generating /build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu/bindings/java/apidoc/overview-tree.html...
Generating /build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu/bindings/java/apidoc/index.html...
Generating /build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu/bindings/java/apidoc/allclasses-index.html...
Building index for all classes...
Generating /build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu/bindings/java/apidoc/allpackages-index.html...
Generating /build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu/bindings/java/apidoc/index-all.html...
Generating /build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu/bindings/java/apidoc/search.html...
Generating /build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu/bindings/java/apidoc/overview-summary.html...
Generating /build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu/bindings/java/apidoc/help-doc.html...
The generated documentation contains diagnostic markers for invalid input.
3 warnings
cd /build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu/bindings/java && echo

make[3]: Leaving directory '/build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu'
[ 37%] Built target NexusJavadocBuild
make[2]: Leaving directory '/build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu'
make[1]: *** [Makefile:169: all] Error 2
make[1]: Leaving directory '/build/reproducible-path/nexus-4.4.3/obj-aarch64-linux-gnu'
dh_auto_build: error: cd obj-aarch64-linux-gnu && make -j128 INSTALL="install --strip-program=true" VERBOSE=1 returned exit code 2
make: *** [debian/rules:7: binary] Error 25
dpkg-buildpackage: error: debian/rules binary subprocess failed with exit status 2

We believe that the bug you reported is fixed in the latest version of
nexus, which is due to be installed in the Debian FTP archive.

A summary of the changes between this version and the previous one is
attached.

Thank you for reporting the bug, which will now be closed.  If you
have further comments please address them to 1133575@bugs.debian.org,
and the maintainer will reopen the bug report if appropriate.

Debian distribution maintenance software
pp.
Stuart Prescott <stuart@debian.org> (supplier of updated nexus package)

(This message was generated automatically at their request; if you
believe that there is a problem with it please contact the archive
administrators by mailing ftpmaster@ftp-master.debian.org)
Format: 1.8
Date: Mon, 03 Aug 2026 16:07:21 +1000
Source: nexus
Architecture: source
Version: 4.4.3-11
Distribution: unstable
Urgency: medium
Maintainer: Debian Science Maintainers <debian-science-maintainers@lists.alioth.debian.org>
Changed-By: Stuart Prescott <stuart@debian.org>
Closes: 1133575
Changes:
 nexus (4.4.3-11) unstable; urgency=medium
 .
   * Fix FTBFS with GCC-16 (Closes: #1133575).
   * Update Standards-Version to 4.7.4 (no changes required).
   * Update to debhelper compat 14.
   * Refresh patches through gbp pq.
Checksums-Sha1:
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 300376d128e72b1bae85ac22b7298bfdc87de5dc 13368 nexus_4.4.3-11.debian.tar.xz
 635f997609e839d1067426b6c8ffb66b45133e5d 14835 nexus_4.4.3-11_amd64.buildinfo
Checksums-Sha256:
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Files:
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 1a52327dcfcf105441c3cb999dce7377 13368 science optional nexus_4.4.3-11.debian.tar.xz
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