[PATCH v2] doc: Sphinx.override_domain() deprecated

[Heinrich Schuchardt]

Sphinx.override_domain() is deprecated since Sphinx 1.8 and removed in
Sphinx 3.

Use Sphinx.add_domain(, override=True) instead.

Signed-off-by: Heinrich Schuchardt <xypron.glpk at gmx.de>
---
v2:
	Ubuntu 18.04 still uses Sphinx 1.6.7
	So use the same version check as Linux.
---
 doc/sphinx/cdomain.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/doc/sphinx/cdomain.py b/doc/sphinx/cdomain.py
index cf13ff3a65..e0c762caa6 100644
--- a/doc/sphinx/cdomain.py
+++ b/doc/sphinx/cdomain.py
@@ -48,7 +48,10 @@ major, minor, patch = sphinx.version_info[:3]

 def setup(app):

-    app.override_domain(CDomain)
+    if (major == 1 and minor < 8):
+        app.override_domain(CDomain)
+    else:
+        app.add_domain(CDomain, override=True)

     return dict(
         version = __version__,
--
2.28.0