#1135498 fmtlib: FTBFS: TypeError("argument of type '_CascadingStyleSheet' is not iterable")

Package:
src:fmtlib
Source:
src:fmtlib
Submitter:
Santiago Vila
Date:
2026-05-01 23:31:04 UTC
Severity:
normal
Tags:
#1135498#5
Date:
2026-05-01 23:29:11 UTC
From:
To:
Dear maintainer:

During a rebuild of all packages in unstable, this package failed to build.

Below you will find the last part of the build log (probably the most
relevant part, but not necessarily). If required, the full build log
is available here:

https://people.debian.org/~sanvila/build-logs/202605/

About the archive rebuild: The build was made on virtual machines from AWS,
using sbuild and a reduced chroot with only build-essential packages.

If you cannot reproduce the bug please contact me privately, as I
am willing to provide ssh access to a virtual machine where the bug is
fully reproducible.

If this is really a bug in one of the build-depends, please use
reassign and add an affects on src:fmtlib, so that this is still
visible in the BTS web page for this package.

Thanks.
--------------------------------------------------------------------------------
[...]
/<<PKGBUILDDIR>>/include/fmt/format.h:1567: warning: Member kappa (variable) of struct fmt::detail::dragonbox::float_info< double > is not documented.
/<<PKGBUILDDIR>>/include/fmt/format.h:1568: warning: Member big_divisor (variable) of struct fmt::detail::dragonbox::float_info< double > is not documented.
/<<PKGBUILDDIR>>/include/fmt/format.h:1569: warning: Member small_divisor (variable) of struct fmt::detail::dragonbox::float_info< double > is not documented.
/<<PKGBUILDDIR>>/include/fmt/format.h:1570: warning: Member min_k (variable) of struct fmt::detail::dragonbox::float_info< double > is not documented.
/<<PKGBUILDDIR>>/include/fmt/format.h:1571: warning: Member max_k (variable) of struct fmt::detail::dragonbox::float_info< double > is not documented.
/<<PKGBUILDDIR>>/include/fmt/format.h:1572: warning: Member shorter_interval_tie_lower_threshold (variable) of struct fmt::detail::dragonbox::float_info< double > is not documented.
/<<PKGBUILDDIR>>/include/fmt/format.h:1573: warning: Member shorter_interval_tie_upper_threshold (variable) of struct fmt::detail::dragonbox::float_info< double > is not documented.
/<<PKGBUILDDIR>>/include/fmt/format.h:1581: warning: Member carrier_uint (typedef) of struct fmt::detail::dragonbox::float_info< T, enable_if_t< std::numeric_limits< T >::digits==64||std::numeric_limits< T >::digits==113||is_float128< T >::value > > is not documented.
/<<PKGBUILDDIR>>/include/fmt/format.h:1582: warning: Member exponent_bits (variable) of struct fmt::detail::dragonbox::float_info< T, enable_if_t< std::numeric_limits< T >::digits==64||std::numeric_limits< T >::digits==113||is_float128< T >::value > > is not documented.
/<<PKGBUILDDIR>>/include/fmt/format.h:1588: warning: Member carrier_uint (typedef) of struct fmt::detail::dragonbox::float_info< T, enable_if_t< is_double_double< T >::value > > is not documented.
/<<PKGBUILDDIR>>/include/fmt/format.h:1592: warning: Member significand_type (typedef) of struct fmt::detail::dragonbox::decimal_fp is not documented.
/<<PKGBUILDDIR>>/include/fmt/format.h:1593: warning: Member significand (variable) of struct fmt::detail::dragonbox::decimal_fp is not documented.
/<<PKGBUILDDIR>>/include/fmt/format.h:1594: warning: Member exponent (variable) of struct fmt::detail::dragonbox::decimal_fp is not documented.
sphinx-build -Dbreathe_projects.format=../bdir/doxyxml \
	-Dversion=10.1.1+ds1-4 -Drelease=10.1.1+ds1-4 -Aversion=10.1.1+ds1-4 -Aversions=10.1.1+ds1-4 \
	-b html doc/ bdir/libfmt-doc
Running Sphinx v9.1.0
loading translations [en]... done
making output directory... done
Converting `source_suffix = '.rst'` to `source_suffix = {'.rst': 'restructuredtext'}`.
building [mo]: targets for 0 po files that are out of date
writing output...
building [html]: targets for 5 source files that are out of date
updating environment: [new config] 5 added, 0 changed, 0 removed
reading sources... [ 20%] api
reading sources... [ 40%] contents
reading sources... [ 60%] index
reading sources... [ 80%] syntax
reading sources... [100%] usage

/<<PKGBUILDDIR>>/doc/api.rst:259: WARNING: doxygenfunction: Unable to resolve function "fmt::arg" with arguments (const S&, const T&) in doxygen xml output for project "format" from directory: ../bdir/doxyxml.
Potential matches:
- template<typename Char, typename T> detail::named_arg<Char, T> arg(const Char *name, const T &arg) [docutils]
/<<PKGBUILDDIR>>/doc/api.rst:291: WARNING: doxygenfunction: Unable to resolve function "fmt::make_format_args" with arguments (const Args&...) in doxygen xml output for project "format" from directory: ../bdir/doxyxml.
Potential matches:
- template<typename Context = format_context, typename ...T> format_arg_store<Context, remove_cvref_t<T>...> make_format_args(T&... args) [docutils]
/<<PKGBUILDDIR>>/doc/api.rst:344: WARNING: doxygenfunction: Unable to resolve function "operator""_a" with arguments () in doxygen xml output for project "format" from directory: ../bdir/doxyxml.
Potential matches:
- detail::udl_arg<char> operator""_a(const char *s, size_t)
- detail::udl_arg<wchar_t> operator""_a(const wchar_t *s, size_t) [docutils]
/<<PKGBUILDDIR>>/doc/api.rst:509: WARNING: doxygenfunction: Cannot find function "localtime" in doxygen xml output for project "format" from directory: ../bdir/doxyxml [docutils]
/<<PKGBUILDDIR>>/doc/api.rst:511: WARNING: doxygenfunction: Cannot find function "gmtime" in doxygen xml output for project "format" from directory: ../bdir/doxyxml [docutils]
/<<PKGBUILDDIR>>/doc/api.rst:569: WARNING: doxygenfunction: Cannot find function "operator""_cf" in doxygen xml output for project "format" from directory: ../bdir/doxyxml [docutils]
/<<PKGBUILDDIR>>/doc/api.rst:580: WARNING: doxygenfunction: Unable to resolve function "fg" with arguments (detail::color_type) in doxygen xml output for project "format" from directory: ../bdir/doxyxml.
Potential matches:
- text_style fg(detail::color_type foreground)
- text_style fg(detail::color_type foreground) [docutils]
/<<PKGBUILDDIR>>/doc/api.rst:582: WARNING: doxygenfunction: Unable to resolve function "bg" with arguments (detail::color_type) in doxygen xml output for project "format" from directory: ../bdir/doxyxml.
Potential matches:
- text_style bg(detail::color_type background)
- text_style bg(detail::color_type background) [docutils]
/<<PKGBUILDDIR>>/doc/api.rst:594: ERROR: Error in "doxygenfunction" directive:
unknown option: "members".

.. doxygenfunction:: fmt::windows_error
   :members: [docutils]
/<<PKGBUILDDIR>>/doc/api.rst:654: WARNING: doxygentypedef: Cannot find typedef "fmt::wstring_view" in doxygen xml output for project "format" from directory: ../bdir/doxyxml [docutils]
looking for now-outdated files... none found
pickling environment... done
checking consistency... /<<PKGBUILDDIR>>/doc/contents.rst: WARNING: document isn't included in any toctree [toc.not_included]
done
preparing documents... done
copying assets...
copying static files...
Writing evaluated template result to /<<PKGBUILDDIR>>/bdir/libfmt-doc/_static/documentation_options.js
Writing evaluated template result to /<<PKGBUILDDIR>>/bdir/libfmt-doc/_static/language_data.js
Writing evaluated template result to /<<PKGBUILDDIR>>/bdir/libfmt-doc/_static/basic.css
copying static files: done
copying extra files...
copying extra files: done
copying assets: done
writing output... [ 20%] api
/<<PKGBUILDDIR>>/doc/api.rst:79: WARNING: Unparseable C++ cross-reference: 'str.format'
Error in cross-reference.
If shorthand ref:
  Invalid C++ declaration: Expected end of definition. [error at 3]
    str.format
    ---^
If full function ref:
  Error when parsing function declaration.
  If the function has no return type:
    Error in declarator or parameters-and-qualifiers
    Invalid C++ declaration: Expecting "(" in parameters-and-qualifiers. [error at 3]
      str.format
      ---^
  If the function has a return type:
    Error in declarator or parameters-and-qualifiers
    If pointer to member declarator:
      Invalid C++ declaration: Expected identifier in nested name. [error at 3]
        str.format
        ---^
    If declarator-id:
      Invalid C++ declaration: Expected identifier in nested name. [error at 3]
        str.format
        ---^


Theme error!

Versions
========

* Platform:         linux; (Linux-6.12.74+deb13+1-cloud-amd64-x86_64-with-glibc2.42)
* Python version:   3.13.12 (CPython)
* Sphinx version:   9.1.0
* Docutils version: 0.22.4
* Jinja2 version:   3.1.6
* Pygments version: 2.19.2

Last Messages
=============

    Writing evaluated template result to /<<PKGBUILDDIR>>/bdir/libfmt-doc/_static/documentation_options.js
    Writing evaluated template result to /<<PKGBUILDDIR>>/bdir/libfmt-doc/_static/language_data.js
    Writing evaluated template result to /<<PKGBUILDDIR>>/bdir/libfmt-doc/_static/basic.css
    copying static files: done
    copying extra files...
    copying extra files: done
    copying assets: done
    writing output... [ 20%]
    api

Loaded Extensions
=================

* sphinx.ext.mathjax (9.1.0)
* alabaster (1.0.0)
* sphinx.ext.ifconfig (9.1.0)
* breathe (4.36.0)

Traceback
=========

      File "/usr/lib/python3/dist-packages/sphinx/builders/html/__init__.py", line 1238, in handle_page
        raise ThemeError(msg) from exc
    sphinx.errors.ThemeError: An error happened in rendering the page api.
    Reason: TypeError("argument of type '_CascadingStyleSheet' is not iterable")


The full traceback has been saved in:
/tmp/sphinx-err-hopp6k18.log

To report this error to the developers, please open an issue at <https://github.com/sphinx-doc/sphinx/issues/>. Thanks!
Please also report this if it was a user error, so that a better error message can be provided next time.
make[1]: *** [debian/rules:19: override_dh_auto_build-indep] Error 2
make[1]: Leaving directory '/<<PKGBUILDDIR>>'
make: *** [debian/rules:6: binary] Error 2
dpkg-buildpackage: error: debian/rules binary subprocess failed with exit status 2
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