tree:   git://git.kernel.org/pub/scm/linux/kernel/git/ardb/linux.git remove-ia64
head:   f1da0a6d10c7d3e0519ea03e9eb03241e3e93da0
commit: f1da0a6d10c7d3e0519ea03e9eb03241e3e93da0 [1/1] arch: Remove Itanium (IA-64) architecture
reproduce:
        # https://git.kernel.org/pub/scm/linux/kernel/git/ardb/linux.git/commit/?id=f1da0a6d10c7d3e0519ea03e9eb03241e3e93da0
        git remote add ardb git://git.kernel.org/pub/scm/linux/kernel/git/ardb/linux.git
        git fetch --no-tags ardb remove-ia64
        git checkout f1da0a6d10c7d3e0519ea03e9eb03241e3e93da0
        make menuconfig
        # enable CONFIG_COMPILE_TEST, CONFIG_WARN_MISSING_DOCUMENTS, CONFIG_WARN_ABI_ERRORS
        make htmldocs

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> Documentation/arch.rst:9: WARNING: toctree contains reference to nonexisting document 'ia64/index'

vim +9 Documentation/arch.rst

3eca1cfbc1e854 Jonathan Neuschäfer 2021-03-12  8  
3eca1cfbc1e854 Jonathan Neuschäfer 2021-03-12 @9  .. toctree::

:::::: The code at line 9 was first introduced by commit
:::::: 3eca1cfbc1e854aafd1672d408c4b8fc602a20e3 docs: Group arch-specific documentation under "CPU Architectures"

:::::: TO: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
:::::: CC: Jonathan Corbet <corbet@lwn.net>

-- 
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https://01.org/lkp