From 8187382f7122a6e826e4b9f756242df561e95464 Mon Sep 17 00:00:00 2001
From: Elliott Sales de Andrade <quantum.analyst@gmail.com>
Date: Sat, 3 Dec 2022 01:20:08 -0500
Subject: [PATCH] DOC: Don't try to link paths that are on a different drive

This may happen if Python is installed on C: and Matplotlib is installed
on some other drive. As the point of this extension is to create GitHub
links for Matplotlib *only*, we should ignore all paths that cannot be
relativized to it.

Fixes #24574
---
 doc/conf.py | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/doc/conf.py b/doc/conf.py
index 654040c95b1c..80282c70a7bb 100644
--- a/doc/conf.py
+++ b/doc/conf.py
@@ -682,7 +682,10 @@ def linkcode_resolve(domain, info):
                     if lineno else "")
 
         startdir = Path(matplotlib.__file__).parent.parent
-        fn = os.path.relpath(fn, start=startdir).replace(os.path.sep, '/')
+        try:
+            fn = os.path.relpath(fn, start=startdir).replace(os.path.sep, '/')
+        except ValueError:
+            return None
 
         if not fn.startswith(('matplotlib/', 'mpl_toolkits/')):
             return None