Make sure the ']' in the content of the \item[] isn't used as the ending ']'.

Doc/ext.tex

@@ -577,7 +577,7 @@ operator to pass a variable's address.)
 
 \begin{description}
 
-\item[\samp{s} (string) [char *]]
+\item[\samp{s} (string) [char *{]}]
 Convert a Python string to a \C{} pointer to a character string.  You
 must not provide storage for the string itself; a pointer to an
 existing string is stored into the character pointer variable whose

Doc/ext/ext.tex

@@ -577,7 +577,7 @@ operator to pass a variable's address.)
 
 \begin{description}
 
-\item[\samp{s} (string) [char *]]
+\item[\samp{s} (string) [char *{]}]
 Convert a Python string to a \C{} pointer to a character string.  You
 must not provide storage for the string itself; a pointer to an
 existing string is stored into the character pointer variable whose