bug 990669: os.path.normpath may alter the meaning of a path if it contains
symbolic links. This has been documented in a comment since 1992, but is now in
the library reference as well.
diff --git a/Doc/lib/libposixpath.tex b/Doc/lib/libposixpath.tex
index aa790e7..e79df3e 100644
--- a/Doc/lib/libposixpath.tex
+++ b/Doc/lib/libposixpath.tex
@@ -154,7 +154,8 @@
up-level references, e.g. \code{A//B}, \code{A/./B} and
\code{A/foo/../B} all become \code{A/B}. It does not normalize the
case (use \function{normcase()} for that). On Windows, it converts
-forward slashes to backward slashes.
+forward slashes to backward slashes. It should be understood that this may
+change the meaning of the path if it contains symbolic links!
\end{funcdesc}
\begin{funcdesc}{realpath}{path}