Re: [RFC PATCH] docs: Warn when auto xref to document fails

[Mauro Carvalho Chehab]

Em Thu, 11 Feb 2021 18:10:36 +0000
Nícolas F. R. A. Prado <nfraprado@xxxxxxxxxxxxxx> escreveu:

> Print warning when automarkup fails to cross-reference to another
> document, so that it doesn't fail silently.
> 
> Signed-off-by: Nícolas F. R. A. Prado <nfraprado@xxxxxxxxxxxxxx>
> ---
> 
> This patch is marked as RFC because it causes a lot of new warnings currently.
> So the patch should only be applied after we reduce this to zero. The warnings
> are listed at the end.

Maybe it could be enabled if W=2?

> 
> From this list of warnings, a few are paths that are wrong either due to not
> starting with "Documentation/" or because the document was already converted
> from .txt to .rst but the path wasn't updated. These should be fixed.
> 
> One question that I have about this though, is: would it be better to have a
> single commit fixing all of those documentation-wide or have a separate commit
> for the docs of each subsystem sent to that subsystem's maintainer?
> 
> In any case, a lot of the warnings come from .txt files that aren't part of the
> documentation, and sometimes are only used as examples. This confirms the
> problem of trying to cross-reference to .txt files, as already discussed in [1].
> 
> Looking for which .rst files include .txt files, I ended with the following
> list:
> 
> staging/index.rst:25:.. include:: ../atomic_t.txt
> staging/index.rst:39:.. include:: ../atomic_bitops.txt
> staging/index.rst:53:.. include:: ../memory-barriers.txt
> admin-guide/devices.rst:60:.. include:: devices.txt
> admin-guide/kernel-parameters.rst:208:.. include:: kernel-parameters.txt
> admin-guide/aoe/examples.rst:4: .. include:: udev.txt
> admin-guide/kdump/kdump.rst:544:.. include:: gdbmacros.txt
> translations/ko_KR/index.rst:22:.. include:: ./memory-barriers.txt
> netlabel/draft_ietf.rst:4: .. include:: draft-ietf-cipso-ipsecurity-01.txt
> sparc/oradax/oracle-dax.rst:444: .. include:: dax-hv-api.txt
> 
> Since it is a quite short list, it seems that having a .txt file inside a .rst
> is the exception rather than the norm. So, in order to continue to have links
> to, for example, kernel-parameters.txt pointing to kernel-parameters.rst without
> changing the documentation, I propose for us to have a mapping inside
> automarkup.py. This would map the .txt to the .rst files and link to them
> instead. If the .txt isn't present in the mapping, it would simply be ignored,
> not even a warning would be printed.
> 
> With this mapping, the links to these special .txt documents would continue to
> work without us trying to link to any other .txt file, which is great since most
> of the time it doesn't make sense. And since these .txt files are there for
> established purposes, I don't think new ones will be created, so there won't be
> a burden in maintaining this mapping updated.
> 
> Thoughts?
> 
> Thanks,
> Nícolas
> 
> [1] https://lore.kernel.org/linux-doc/C91700MG55NC.EQS8AQE2J1DB@ArchWay/
> 
> Warnings generated:
> 
> WARNING: PCI/pci-error-recovery: Failed to cross-reference to document powerpc/eeh-pci-error-recovery.txt
> WARNING: RCU/Design/Data-Structures/Data-Structures: Failed to cross-reference to document timers/NO_HZ.txt
> WARNING: RCU/rcu: Failed to cross-reference to document Documentation/RCU/RTFP.txt
> WARNING: RCU/rcu: Failed to cross-reference to document Documentation/RCU/RTFP.txt
> WARNING: RCU/rcu_dereference: Failed to cross-reference to document Documentation/memory-barriers.txt
> WARNING: RCU/torture: Failed to cross-reference to document testid.txt
> WARNING: admin-guide/abi-stable: Failed to cross-reference to document spkguide.txt
> WARNING: admin-guide/abi-testing: Failed to cross-reference to document Documentation/devicetree/bindings/mfd/bd9571mwv.txt
> WARNING: admin-guide/abi-testing: Failed to cross-reference to document Documentation/devicetree/bindings/leds/leds-trigger-pattern.txt
> WARNING: admin-guide/abi-testing: Failed to cross-reference to document docs/specs/fw_cfg.txt
> WARNING: admin-guide/aoe/aoe: Failed to cross-reference to document com/documents/AoEr11.txt
> WARNING: admin-guide/aoe/aoe: Failed to cross-reference to document udev.txt
> WARNING: admin-guide/bug-hunting: Failed to cross-reference to document Documentation/admin-guide/kdump/gdbmacros.txt
> WARNING: admin-guide/cputopology: Failed to cross-reference to document cpu-hotplug.txt
> WARNING: admin-guide/cputopology: Failed to cross-reference to document cpu-hotplug.txt
> WARNING: admin-guide/ext4: Failed to cross-reference to document Documentation/filesystems/dax.txt
> WARNING: admin-guide/hw-vuln/l1tf: Failed to cross-reference to document org/doc/Documentation/admin-guide/cgroup-v1/cpusets.rst
> WARNING: admin-guide/hw-vuln/l1tf: Failed to cross-reference to document org/doc/Documentation/core-api/irq/irq-affinity.rst
> WARNING: admin-guide/java: Failed to cross-reference to document binfmt_misc.txt
> WARNING: admin-guide/reporting-issues: Failed to cross-reference to document admin-guide/bug-hunting.rst
> WARNING: admin-guide/sysctl/fs: Failed to cross-reference to document intro.rst
> WARNING: admin-guide/unicode: Failed to cross-reference to document org/docs/unicode/admin-guide/unicode.rst
> WARNING: arm/keystone/knav-qmss: Failed to cross-reference to document Documentation/devicetree/bindings/soc/ti/keystone-navigator-qmss.txt
> WARNING: arm/keystone/overview: Failed to cross-reference to document Documentation/devicetree/bindings/arm/keystone/keystone.txt
> WARNING: arm/samsung-s3c24xx/overview: Failed to cross-reference to document EB2410ITX.txt
> WARNING: arm/samsung-s3c24xx/overview: Failed to cross-reference to document GPIO.txt
> WARNING: arm/samsung-s3c24xx/overview: Failed to cross-reference to document Suspend.txt
> WARNING: core-api/circular-buffers: Failed to cross-reference to document Documentation/memory-barriers.txt
> WARNING: core-api/debugging-via-ohci1394: Failed to cross-reference to document README.txt
> WARNING: core-api/dma-api-howto: Failed to cross-reference to document DMA-API.txt
> WARNING: core-api/kernel-api: Failed to cross-reference to document c.txt
> WARNING: core-api/kernel-api: Failed to cross-reference to document Documentation/core-api/atomic_ops.rst
> WARNING: core-api/refcount-vs-atomic: Failed to cross-reference to document tools/memory-model/Documentation/explanation.txt
> WARNING: core-api/refcount-vs-atomic: Failed to cross-reference to document memory-barriers.txt
> WARNING: core-api/refcount-vs-atomic: Failed to cross-reference to document atomic_t.txt
> WARNING: core-api/refcount-vs-atomic: Failed to cross-reference to document memory-barriers.txt
> WARNING: dev-tools/coccinelle: Failed to cross-reference to document com/coccinelle/coccinelle/blob/master/install.txt
> WARNING: devicetree/bindings/submitting-patches: Failed to cross-reference to document bindings/ABI.txt
> WARNING: devicetree/bindings/writing-bindings: Failed to cross-reference to document property-units.txt
> WARNING: driver-api/console: Failed to cross-reference to document fbcon.txt
> WARNING: driver-api/fpga/fpga-region: Failed to cross-reference to document ../devicetree/bindings/fpga/fpga-region.txt
> WARNING: driver-api/gpio/board: Failed to cross-reference to document gpio-legacy.txt
> WARNING: driver-api/gpio/consumer: Failed to cross-reference to document gpio-legacy.txt
> WARNING: driver-api/gpio/index: Failed to cross-reference to document Documentation/devicetree/bindings/gpio/gpio.txt
> WARNING: driver-api/gpio/index: Failed to cross-reference to document Documentation/devicetree/bindings/gpio/gpio.txt
> WARNING: driver-api/gpio/intro: Failed to cross-reference to document gpio-legacy.txt
> WARNING: driver-api/gpio/intro: Failed to cross-reference to document gpio-legacy.txt
> WARNING: driver-api/gpio/intro: Failed to cross-reference to document gpio-legacy.txt
> WARNING: driver-api/gpio/legacy: Failed to cross-reference to document Documentation/devicetree/bindings/gpio/gpio.txt
> WARNING: driver-api/isapnp: Failed to cross-reference to document pnp.txt
> WARNING: driver-api/media/drivers/cx88-devel: Failed to cross-reference to document edu/circuit_archive/text/ir_decode.txt
> WARNING: driver-api/media/drivers/dvb-usb: Failed to cross-reference to document vp7041.txt
> WARNING: driver-api/miscellaneous: Failed to cross-reference to document Documentation/devicetree/bindings/serial/rs485.txt
> WARNING: driver-api/nvmem: Failed to cross-reference to document Documentation/devicetree/bindings/nvmem/nvmem.txt
> WARNING: driver-api/phy/phy: Failed to cross-reference to document Documentation/devicetree/bindings/phy/phy-bindings.txt
> WARNING: driver-api/pinctl: Failed to cross-reference to document Documentation/devicetree/bindings/gpio/gpio.txt
> WARNING: driver-api/rfkill: Failed to cross-reference to document admin-guide/kernel-parameters.rst
> WARNING: driver-api/serial/serial-rs485: Failed to cross-reference to document Documentation/devicetree/bindings/serial/rs485.txt
> WARNING: fb/cmap_xfbdev: Failed to cross-reference to document rgb.txt
> WARNING: fb/framebuffer: Failed to cross-reference to document xc/programs/Xserver/hw/xfree86/doc/modeDB.txt
> WARNING: filesystems/ext2: Failed to cross-reference to document Documentation/filesystems/dax.txt
> WARNING: filesystems/nfs/rpc-server-gss: Failed to cross-reference to document org/rfc/rfc2203.txt
> WARNING: filesystems/nfs/rpc-server-gss: Failed to cross-reference to document org/rfc/rfc5403.txt
> WARNING: filesystems/nfs/rpc-server-gss: Failed to cross-reference to document org/rfc/rfc7861.txt
> WARNING: filesystems/ramfs-rootfs-initramfs: Failed to cross-reference to document buffer-format.txt
> WARNING: filesystems/sysfs: Failed to cross-reference to document /fuse.txt
> WARNING: filesystems/ubifs-authentication: Failed to cross-reference to document org/doc/Documentation/device-mapper/dm-integrity.rst
> WARNING: filesystems/ubifs-authentication: Failed to cross-reference to document org/doc/Documentation/device-mapper/verity.rst
> WARNING: filesystems/vfat: Failed to cross-reference to document longfilename.txt
> WARNING: filesystems/vfat: Failed to cross-reference to document longfile.txt
> WARNING: filesystems/vfat: Failed to cross-reference to document longfile.txt
> WARNING: filesystems/vfat: Failed to cross-reference to document 1.txt
> WARNING: firmware-guide/acpi/dsd/graph: Failed to cross-reference to document Documentation/devicetree/bindings/graph.txt
> WARNING: firmware-guide/acpi/dsd/leds: Failed to cross-reference to document Documentation/devicetree/bindings/leds/common.txt
> WARNING: firmware-guide/acpi/dsd/leds: Failed to cross-reference to document Documentation/devicetree/bindings/media/video-interfaces.txt
> WARNING: firmware-guide/acpi/gpio-properties: Failed to cross-reference to document Documentation/devicetree/bindings/gpio/gpio.txt
> WARNING: firmware-guide/acpi/video_extension: Failed to cross-reference to document admin-guide/kernel-parameters.rst
> WARNING: gpu/drm-kms-helpers: Failed to cross-reference to document Documentation/devicetree/bindings/graph.txt
> WARNING: gpu/drm-kms-helpers: Failed to cross-reference to document Documentation/devicetree/bindings/graph.txt
> WARNING: hwmon/g762: Failed to cross-reference to document Documentation/devicetree/bindings/hwmon/g762.txt
> WARNING: hwmon/ina2xx: Failed to cross-reference to document Documentation/devicetree/bindings/hwmon/ina2xx.txt
> WARNING: hwmon/scpi-hwmon: Failed to cross-reference to document scpi.txt
> WARNING: hwmon/vexpress: Failed to cross-reference to document Documentation/devicetree/bindings/hwmon/vexpress.txt
> WARNING: infiniband/ipoib: Failed to cross-reference to document org/rfc/rfc4391.txt
> WARNING: infiniband/ipoib: Failed to cross-reference to document org/rfc/rfc4392.txt
> WARNING: infiniband/ipoib: Failed to cross-reference to document org/rfc/rfc4755.txt
> WARNING: input/ff: Failed to cross-reference to document joystick.txt
> WARNING: input/ff: Failed to cross-reference to document joystick.txt
> WARNING: leds/leds-class-multicolor: Failed to cross-reference to document led-class.rst
> WARNING: locking/futex-requeue-pi: Failed to cross-reference to document rt-mutex-desgin.txt
> WARNING: locking/spinlocks: Failed to cross-reference to document Documentation/memory-barriers.txt
> WARNING: misc-devices/xilinx_sdfec: Failed to cross-reference to document sd-fec.txt
> WARNING: netlabel/cipso_ipv4: Failed to cross-reference to document draft-ietf-cipso-ipsecurity-01.txt
> WARNING: networking/device_drivers/ethernet/altera/altera_tse: Failed to cross-reference to document org/rfc/rfc2863.txt
> WARNING: networking/device_drivers/ethernet/altera/altera_tse: Failed to cross-reference to document org/rfc/rfc2819.txt
> WARNING: networking/device_drivers/ethernet/cirrus/cs89x0: Failed to cross-reference to document readme.txt
> WARNING: networking/device_drivers/ethernet/freescale/dpaa2/overview: Failed to cross-reference to document qoriq-mc.txt
> WARNING: networking/device_drivers/ethernet/intel/e100: Failed to cross-reference to document /Documentation/networking/bonding.rst
> WARNING: networking/device_drivers/ethernet/intel/e1000: Failed to cross-reference to document networking/ip-sysctl.txt
> WARNING: networking/device_drivers/ethernet/intel/ixgb: Failed to cross-reference to document /Documentation/networking/bonding.rst
> WARNING: networking/device_drivers/ethernet/intel/ixgb: Failed to cross-reference to document networking/ip-sysctl.txt
> WARNING: networking/filter: Failed to cross-reference to document test_in.txt
> WARNING: networking/filter: Failed to cross-reference to document test_out.txt
> WARNING: networking/ip-sysctl: Failed to cross-reference to document org/id/draft-nishida-tsvwg-sctp-failover-05.txt
> WARNING: networking/kapi: Failed to cross-reference to document phy_driver.txt
> WARNING: networking/mac80211-injection: Failed to cross-reference to document /Documentation/networking/radiotap-headers.rst
> WARNING: networking/sctp: Failed to cross-reference to document org/rfc/rfc2960.txt
> WARNING: networking/timestamping: Failed to cross-reference to document Documentation/devicetree/bindings/ptp/timestamper.txt
> WARNING: networking/udplite: Failed to cross-reference to document uk/users/gerrit/udp-lite/files/UDP-Lite-HOWTO.txt
> WARNING: networking/udplite: Failed to cross-reference to document org/rfc/rfc3828.txt
> WARNING: power/power_supply_class: Failed to cross-reference to document Documentation/devicetree/bindings/power/supply/battery.txt
> WARNING: process/8.Conclusion: Failed to cross-reference to document process/howto.rst
> WARNING: process/8.Conclusion: Failed to cross-reference to document process/submitting-patches.rst
> WARNING: process/8.Conclusion: Failed to cross-reference to document process/submitting-drivers.rst
> WARNING: process/coding-style: Failed to cross-reference to document process/coding-style.rst
> WARNING: process/howto: Failed to cross-reference to document akpm/stuff/tpp.txt
> WARNING: process/howto: Failed to cross-reference to document akpm/stuff/tpp.txt
> WARNING: process/management-style: Failed to cross-reference to document process/coding-style.rst
> WARNING: process/submitting-patches: Failed to cross-reference to document akpm/stuff/tpp.txt
> WARNING: scheduler/sched-bwc: Failed to cross-reference to document Documentation/admin-guide/cgroupv2.rst
> WARNING: scheduler/sched-capacity: Failed to cross-reference to document Documentation/devicetree/bindings/arm/cpu-capacity.txt
> WARNING: scsi/scsi-generic: Failed to cross-reference to document cz/sg/p/scsi-generic_long.txt
> WARNING: scsi/scsi-generic: Failed to cross-reference to document net/sg/p/original/SCSI-Programming-HOWTO.txt
> WARNING: security/tpm/xen-tpmfront: Failed to cross-reference to document docs/misc/vtpm.txt
> WARNING: sound/alsa-configuration: Failed to cross-reference to document powersave.rst
> WARNING: sound/alsa-configuration: Failed to cross-reference to document hdspm.rst
> WARNING: sound/alsa-configuration: Failed to cross-reference to document MIXART.txt
> WARNING: sound/cards/bt87x: Failed to cross-reference to document btaudio.txt
> WARNING: sound/designs/procfile: Failed to cross-reference to document OSS-Emulation.txt
> WARNING: sound/hd-audio/controls: Failed to cross-reference to document HD-Audio.txt
> WARNING: sound/soc/platform: Failed to cross-reference to document DPCM.txt
> WARNING: sparc/oradax/oracle-dax: Failed to cross-reference to document dax-hv-api.txt
> WARNING: sparc/oradax/oracle-dax: Failed to cross-reference to document dax-hv-api.txt
> WARNING: trace/coresight/coresight: Failed to cross-reference to document Documentation/devicetree/bindings/arm/coresight.txt
> WARNING: trace/coresight/coresight-cpu-debug: Failed to cross-reference to document Documentation/devicetree/bindings/arm/coresight-cpu-debug.txt
> WARNING: trace/ftrace: Failed to cross-reference to document uprobetrace.txt
> WARNING: trace/kprobes: Failed to cross-reference to document tools/perf/Documentation/perf-probe.txt
> WARNING: translations/it_IT/process/1.Intro: Failed to cross-reference to document Intro.rst
> WARNING: translations/it_IT/process/2.Process: Failed to cross-reference to document Process.rst
> WARNING: translations/it_IT/process/3.Early-stage: Failed to cross-reference to document Early-stage.rst
> WARNING: translations/it_IT/process/4.Coding: Failed to cross-reference to document Coding.rst
> WARNING: translations/it_IT/process/5.Posting: Failed to cross-reference to document Posting.rst
> WARNING: translations/it_IT/process/5.Posting: Failed to cross-reference to document translations/it_IT/process/submitting-patches.rst
> WARNING: translations/it_IT/process/5.Posting: Failed to cross-reference to document translations/it_IT/process/submitting-drivers.rst
> WARNING: translations/it_IT/process/5.Posting: Failed to cross-reference to document translations/it_IT/process/submit-checklist.rst
> WARNING: translations/it_IT/process/5.Posting: Failed to cross-reference to document translations/it_IT/process/submitting-patches.rst
> WARNING: translations/it_IT/process/6.Followthrough: Failed to cross-reference to document Followthrough.rst
> WARNING: translations/it_IT/process/7.AdvancedTopics: Failed to cross-reference to document AdvancedTopics.rst
> WARNING: translations/it_IT/process/8.Conclusion: Failed to cross-reference to document Conclusion.rst
> WARNING: translations/it_IT/process/8.Conclusion: Failed to cross-reference to document process/howto.rst
> WARNING: translations/it_IT/process/8.Conclusion: Failed to cross-reference to document process/submitting-patches.rst
> WARNING: translations/it_IT/process/8.Conclusion: Failed to cross-reference to document process/submitting-drivers.rst
> WARNING: translations/it_IT/process/coding-style: Failed to cross-reference to document process/coding-style.rst
> WARNING: translations/it_IT/process/howto: Failed to cross-reference to document akpm/stuff/tpp.txt
> WARNING: translations/it_IT/process/howto: Failed to cross-reference to document admin-guide/reporting-bugs.rst
> WARNING: translations/it_IT/process/howto: Failed to cross-reference to document akpm/stuff/tpp.txt
> WARNING: translations/it_IT/process/management-style: Failed to cross-reference to document translations/it_IT/process/coding-style.rst
> WARNING: translations/it_IT/process/submitting-patches: Failed to cross-reference to document akpm/stuff/tpp.txt
> WARNING: translations/ja_JP/howto: Failed to cross-reference to document akpm/stuff/tpp.txt
> WARNING: translations/ja_JP/howto: Failed to cross-reference to document admin-guide/reporting-bugs.rst
> WARNING: translations/ja_JP/howto: Failed to cross-reference to document akpm/stuff/tpp.txt
> WARNING: translations/ko_KR/howto: Failed to cross-reference to document akpm/stuff/tpp.txt
> WARNING: translations/ko_KR/howto: Failed to cross-reference to document akpm/stuff/tpp.txt
> WARNING: translations/zh_CN/filesystems/tmpfs: Failed to cross-reference to document 请参见Documentation/admin-guide/cgroup-v1/cpusets.rst
> WARNING: translations/zh_CN/iio/iio_configfs: Failed to cross-reference to document 请查阅Documentation/filesystems/configfs.rst
> WARNING: translations/zh_CN/process/1.Intro: Failed to cross-reference to document Intro.rst
> WARNING: translations/zh_CN/process/2.Process: Failed to cross-reference to document Process.rst
> WARNING: translations/zh_CN/process/3.Early-stage: Failed to cross-reference to document Early-stage.rst
> WARNING: translations/zh_CN/process/4.Coding: Failed to cross-reference to document Coding.rst
> WARNING: translations/zh_CN/process/5.Posting: Failed to cross-reference to document Posting.rst
> WARNING: translations/zh_CN/process/6.Followthrough: Failed to cross-reference to document Followthrough.rst
> WARNING: translations/zh_CN/process/7.AdvancedTopics: Failed to cross-reference to document AdvancedTopics.rst
> WARNING: translations/zh_CN/process/8.Conclusion: Failed to cross-reference to document Conclusion.rst
> WARNING: translations/zh_CN/process/8.Conclusion: Failed to cross-reference to document process/submitting-drivers.rst
> WARNING: translations/zh_CN/process/coding-style: Failed to cross-reference to document process/coding-style.rst
> WARNING: translations/zh_CN/process/howto: Failed to cross-reference to document akpm/stuff/tpp.txt
> WARNING: translations/zh_CN/process/howto: Failed to cross-reference to document admin-guide/reporting-bugs.rst
> WARNING: translations/zh_CN/process/howto: Failed to cross-reference to document akpm/stuff/tpp.txt
> WARNING: translations/zh_CN/process/management-style: Failed to cross-reference to document process/coding-style.rst
> WARNING: translations/zh_CN/process/stable-kernel-rules: Failed to cross-reference to document 必须遵循Documentation/translations/zh_CN/process/submitting-patches.rst
> WARNING: translations/zh_CN/process/submitting-patches: Failed to cross-reference to document akpm/stuff/tpp.txt
> WARNING: userspace-api/media/v4l/ext-ctrls-camera: Failed to cross-reference to document video-interfaces.txt
> WARNING: virt/kvm/vcpu-requests: Failed to cross-reference to document Documentation/core-api/atomic_ops.rst
> WARNING: virt/kvm/vcpu-requests: Failed to cross-reference to document Documentation/memory-barriers.txt
> WARNING: vm/hwpoison: Failed to cross-reference to document sysctl.txt
> WARNING: w1/masters/omap-hdq: Failed to cross-reference to document Documentation/devicetree/bindings/w1/omap-hdq.txt
> WARNING: w1/masters/w1-gpio: Failed to cross-reference to document Documentation/devicetree/bindings/w1/w1-gpio.txt
> WARNING: watchdog/hpwdt: Failed to cross-reference to document Documentation/IPMI.txt
> WARNING: x86/intel_txt: Failed to cross-reference to document SINIT-guide.txt
> WARNING: x86/orc-unwinder: Failed to cross-reference to document tools/objtool/Documentation/stack-validation.txt
> WARNING: x86/pti: Failed to cross-reference to document kernel-parameters.txt
> 
> 
>  Documentation/sphinx/automarkup.py | 7 +++++++
>  1 file changed, 7 insertions(+)
> 
> diff --git a/Documentation/sphinx/automarkup.py b/Documentation/sphinx/automarkup.py
> index acf5473002f3..5a03c5080ebe 100644
> --- a/Documentation/sphinx/automarkup.py
> +++ b/Documentation/sphinx/automarkup.py
> @@ -7,6 +7,7 @@
>  from docutils import nodes
>  import sphinx
>  from sphinx import addnodes
> +from sphinx.util import logging
>  if sphinx.version_info[0] < 2 or \
>     sphinx.version_info[0] == 2 and sphinx.version_info[1] < 1:
>      from sphinx.environment import NoUri
> @@ -74,6 +75,8 @@ Skipfuncs = [ 'open', 'close', 'read', 'write', 'fcntl', 'mmap',
>  
>  c_namespace = ''
>  
> +logger = None
> +
>  def markup_refs(docname, app, node):
>      t = node.astext()
>      done = 0
> @@ -257,6 +260,8 @@ def markup_doc_ref(docname, app, match):
>      if xref:
>          return xref
>      else:
> +        logger.warning('{}: Failed to cross-reference to document '
> +                       '{}'.format(docname, match.group(0)))
>          return nodes.Text(match.group(0))
>  
>  def get_c_namespace(app, docname):
> @@ -270,7 +275,9 @@ def get_c_namespace(app, docname):
>  
>  def auto_markup(app, doctree, name):
>      global c_namespace
> +    global logger
>      c_namespace = get_c_namespace(app, name)
> +    logger = logging.getLogger(__name__)
>      #
>      # This loop could eventually be improved on.  Someday maybe we
>      # want a proper tree traversal with a lot of awareness of which



Thanks,
Mauro