[Pkg-cmake-team] Bug#955120: cmake: FTBFS with Sphinx 2.4: Could not import extension cmake (exception: No module named 'sphinxcontrib')

[Lucas Nussbaum]

Source: cmake
Version: 3.16.3-1
Severity: important
Tags: ftbfs
User: python-modules-team at lists.alioth.debian.org
Usertags: sphinx2.4

Hi,

cmake fails to build with Sphinx 2.4, currently available in
experimental.

Relevant part (hopefully):
> make[3]: Entering directory '/<<PKGBUILDDIR>>/Build'
> [  0%] sphinx-build html: see Utilities/Sphinx/build-html.log
> cd /<<PKGBUILDDIR>>/Build/Utilities/Sphinx && /usr/bin/sphinx-build -c /<<PKGBUILDDIR>>/Build/Utilities/Sphinx -d /<<PKGBUILDDIR>>/Build/Utilities/Sphinx/doctrees -b html -D "today=February 02, 2020" /<<PKGBUILDDIR>>/Help /<<PKGBUILDDIR>>/Build/Utilities/Sphinx/html > build-html.log
> [  1%] Building C object Utilities/KWIML/test/CMakeFiles/kwiml_test.dir/test_include_C.c.o
> cd /<<PKGBUILDDIR>>/Build/Utilities/KWIML/test && /usr/bin/gcc -DKWIML_LANGUAGE_C -DKWIML_LANGUAGE_CXX -I/<<PKGBUILDDIR>>/Build/Utilities -I/<<PKGBUILDDIR>>/Utilities -isystem /<<PKGBUILDDIR>>/Utilities/std  -g -O2 -fdebug-prefix-map=/<<PKGBUILDDIR>>=. -fstack-protector-strong -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2 -Wno-format -Wno-format-security   -std=gnu11 -o CMakeFiles/kwiml_test.dir/test_include_C.c.o   -c /<<PKGBUILDDIR>>/Utilities/KWIML/test/test_include_C.c
> [  1%] Building CXX object Utilities/KWIML/test/CMakeFiles/kwiml_test.dir/test_abi_CXX.cxx.o
> cd /<<PKGBUILDDIR>>/Build/Utilities/KWIML/test && /usr/bin/g++  -DKWIML_LANGUAGE_C -DKWIML_LANGUAGE_CXX -I/<<PKGBUILDDIR>>/Build/Utilities -I/<<PKGBUILDDIR>>/Utilities -isystem /<<PKGBUILDDIR>>/Utilities/std  -g -O2 -fdebug-prefix-map=/<<PKGBUILDDIR>>=. -fstack-protector-strong -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2 -Wno-format -Wno-format-security   -std=gnu++17 -o CMakeFiles/kwiml_test.dir/test_abi_CXX.cxx.o -c /<<PKGBUILDDIR>>/Utilities/KWIML/test/test_abi_CXX.cxx
> [  1%] Building CXX object Utilities/KWIML/test/CMakeFiles/kwiml_test.dir/test_int_CXX.cxx.o
> cd /<<PKGBUILDDIR>>/Build/Utilities/KWIML/test && /usr/bin/g++  -DKWIML_LANGUAGE_C -DKWIML_LANGUAGE_CXX -I/<<PKGBUILDDIR>>/Build/Utilities -I/<<PKGBUILDDIR>>/Utilities -isystem /<<PKGBUILDDIR>>/Utilities/std  -g -O2 -fdebug-prefix-map=/<<PKGBUILDDIR>>=. -fstack-protector-strong -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2 -Wno-format -Wno-format-security   -std=gnu++17 -o CMakeFiles/kwiml_test.dir/test_int_CXX.cxx.o -c /<<PKGBUILDDIR>>/Utilities/KWIML/test/test_int_CXX.cxx
> [  1%] Building CXX object Utilities/KWIML/test/CMakeFiles/kwiml_test.dir/test_include_CXX.cxx.o
> cd /<<PKGBUILDDIR>>/Build/Utilities/KWIML/test && /usr/bin/g++  -DKWIML_LANGUAGE_C -DKWIML_LANGUAGE_CXX -I/<<PKGBUILDDIR>>/Build/Utilities -I/<<PKGBUILDDIR>>/Utilities -isystem /<<PKGBUILDDIR>>/Utilities/std  -g -O2 -fdebug-prefix-map=/<<PKGBUILDDIR>>=. -fstack-protector-strong -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2 -Wno-format -Wno-format-security   -std=gnu++17 -o CMakeFiles/kwiml_test.dir/test_include_CXX.cxx.o -c /<<PKGBUILDDIR>>/Utilities/KWIML/test/test_include_CXX.cxx
> 
> Extension error:
> Could not import extension cmake (exception: No module named 'sphinxcontrib')
> [  1%] Building C object Source/kwsys/CMakeFiles/cmsys_c.dir/Base64.c.o
> cd /<<PKGBUILDDIR>>/Build/Source/kwsys && /usr/bin/gcc -DKWSYS_NAMESPACE=cmsys -I/<<PKGBUILDDIR>>/Build/Source -I/<<PKGBUILDDIR>>/Build/Source/kwsys  -g -O2 -fdebug-prefix-map=/<<PKGBUILDDIR>>=. -fstack-protector-strong -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2   -std=gnu11 -o CMakeFiles/cmsys_c.dir/Base64.c.o   -c /<<PKGBUILDDIR>>/Source/kwsys/Base64.c
> [  1%] Building C object Source/kwsys/CMakeFiles/cmsys.dir/Base64.c.o
> cd /<<PKGBUILDDIR>>/Build/Source/kwsys && /usr/bin/gcc -DKWSYS_NAMESPACE=cmsys -I/<<PKGBUILDDIR>>/Build/Source -I/<<PKGBUILDDIR>>/Build/Source/kwsys  -g -O2 -fdebug-prefix-map=/<<PKGBUILDDIR>>=. -fstack-protector-strong -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2   -std=gnu11 -o CMakeFiles/cmsys.dir/Base64.c.o   -c /<<PKGBUILDDIR>>/Source/kwsys/Base64.c
> [  2%] Building C object Source/kwsys/CMakeFiles/cmsys_c.dir/EncodingC.c.o
> cd /<<PKGBUILDDIR>>/Build/Source/kwsys && /usr/bin/gcc -DKWSYS_NAMESPACE=cmsys -DKWSYS_ENCODING_DEFAULT_CODEPAGE=CP_UTF8 -I/<<PKGBUILDDIR>>/Build/Source -I/<<PKGBUILDDIR>>/Build/Source/kwsys  -g -O2 -fdebug-prefix-map=/<<PKGBUILDDIR>>=. -fstack-protector-strong -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2   -std=gnu11 -o CMakeFiles/cmsys_c.dir/EncodingC.c.o   -c /<<PKGBUILDDIR>>/Source/kwsys/EncodingC.c
> [  2%] Building C object Source/kwsys/CMakeFiles/cmsys.dir/EncodingC.c.o
> cd /<<PKGBUILDDIR>>/Build/Source/kwsys && /usr/bin/gcc -DKWSYS_NAMESPACE=cmsys -DKWSYS_ENCODING_DEFAULT_CODEPAGE=CP_UTF8 -I/<<PKGBUILDDIR>>/Build/Source -I/<<PKGBUILDDIR>>/Build/Source/kwsys  -g -O2 -fdebug-prefix-map=/<<PKGBUILDDIR>>=. -fstack-protector-strong -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2   -std=gnu11 -o CMakeFiles/cmsys.dir/EncodingC.c.o   -c /<<PKGBUILDDIR>>/Source/kwsys/EncodingC.c
> make[3]: *** [Utilities/Sphinx/CMakeFiles/documentation.dir/build.make:65: Utilities/Sphinx/doc_format_html] Error 2

The full build log is available from:
   http://qa-logs.debian.net/2020/03/26/cmake_3.16.3-1_unstable_sphinx243.log

Please see [1] for Sphinx changelog, which may give a hint of what changes in
Sphinx caused this error.

Also see [2] for the list of deprecated/removed APIs and possible alternatives
to them.

Sphinx 2.4 is going to be uploaded to unstable in a couple of weeks. When that
happens, the severity of this bug will be bumped to serious.

In case you have questions, please Cc sphinx at packages.debian.org on reply.

[1]: https://www.sphinx-doc.org/en/2.0/changes.html
[2]: https://www.sphinx-doc.org/en/2.0/extdev/deprecated.html#dev-deprecated-apis

A list of current common problems and possible solutions is available at
http://wiki.debian.org/qa.debian.org/FTBFS . You're welcome to contribute!

About the archive rebuild: The rebuild was done on EC2 VM instances from
Amazon Web Services, using a clean, minimal and up-to-date chroot. Every
failed build was retried once to eliminate random failures.