bpo-40204: Allow pre-Sphinx 3 syntax in the doc (GH-21844)
Enable Sphinx 3.2 "c_allow_pre_v3" option and disable the
c_warn_on_allowed_pre_v3 option to make the documentation compatible
with Sphinx 2 and Sphinx 3.
diff --git a/Doc/conf.py b/Doc/conf.py
index bfb2a98..079d177 100644
--- a/Doc/conf.py
+++ b/Doc/conf.py
@@ -228,3 +228,13 @@
# Relative filename of the reference count data file.
refcount_file = 'data/refcounts.dat'
+
+# Sphinx 2 and Sphinx 3 compatibility
+# -----------------------------------
+
+# bpo-40204: Allow Sphinx 2 syntax in the C domain
+c_allow_pre_v3 = True
+
+# bpo-40204: Disable warnings on Sphinx 2 syntax of the C domain since the
+# documentation is built with -W (warnings treated as errors).
+c_warn_on_allowed_pre_v3 = False