sphinx 1.8.1 build errors with "Inconsistency detected by ld.so: dl-version.c: 224 ..."

[jcmgray]

Details

• Read the Docs project URL: https://readthedocs.org/projects/quimb/
• Build URL (if applicable): https://readthedocs.org/projects/quimb/builds/7830573/ (first broken build)
• Read the Docs username (if applicable): jcmgray

Expected Result

The documentation built without hitch until it seems sphinx changed from v1.8.0 to v1.8.1. The actual commit which was broken first wasn't docs related but I see from the logs the sphinx version did change.

Actual Result

At the build stage I get the error:

Running Sphinx v1.8.1
Inconsistency detected by ld.so: dl-version.c: 224: _dl_check_map_versions: Assertion `needed != NULL' failed!

---

other notes / attempted troubleshooting:

• I have tried setting sphinx=1.8.0 in the conda dependency yaml (and wiping the build) but this hasn't had an effect, I think as the command conda install --yes --name develop mock pillow sphinx sphinx_rtd_theme is run subsequently and ends updating to 1.8.1.
• The sphinx release notes for 1.8.1 don't seem to mention applicable breaking changes.
• I tried reverting the build image to 2.0 from latest with no effect.
• The docs build locally (ubuntu 18.04 + conda) with sphinx=1.8.1 without issue.

[stsewd]

Maybe this is a sphinx bug? Also, to pin dependencies using conda we have this #3829 (we are waiting for a conda release)

[stsewd]

Not sure if this is the same sphinx-doc/sphinx#5496

[jcmgray]

Yes apologies if this issue is misplaced (feel free to close)! My reason for raising here was just that building with sphinx=1.8.1works fine for me locally so thought it might be some interaction with the readthedocs machinery. I'll keep an eye on those other issues.

[stsewd]

Not worries, I'll try to reproduce this locally later and see where the problem is

[stsewd]

I'll try to reproduce this locally later and see where the problem is

Conda is really heavy for my computer, I'm hitting my memory limit before the build ends :/

[jcmgray]

Closing as the docs now seem to be working - I've had a quick look in the logs but couldn't see any particular changes that might explain it. @stsewd thanks very much for taking a look!