# HG changeset patch
# User Zackery Spytz <zspytz@gmail.com>
# Date 1618241971 21600
#      Mon Apr 12 09:39:31 2021 -0600
# Node ID edce566aaa12ee831e617b9dc8d63396f9b6e5df
# Parent  bbbfa0724f5f18544264d7ca576efadfb9c32815
bpo-41661: Document os.path.relpath() exception on Windows with different drives (GH-25346)

diff --git a/Doc/library/os.path.rst b/Doc/library/os.path.rst
--- a/Doc/library/os.path.rst
+++ b/Doc/library/os.path.rst
@@ -366,7 +366,8 @@
    Return a relative filepath to *path* either from the current directory or
    from an optional *start* directory.  This is a path computation:  the
    filesystem is not accessed to confirm the existence or nature of *path* or
-   *start*.
+   *start*.  On Windows, :exc:`ValueError` is raised when *path* and *start*
+   are on different drives.
 
    *start* defaults to :attr:`os.curdir`.