PyCObject_FromVoidPtr(): Clarify that the destr function will only be
called on destruction is non-NULL.
diff --git a/Doc/api/api.tex b/Doc/api/api.tex
index 4cce62b..a625d14 100644
--- a/Doc/api/api.tex
+++ b/Doc/api/api.tex
@@ -2384,7 +2384,8 @@
\begin{cfuncdesc}{PyObject *}{PyCObject_FromVoidPtr}{void* cobj,
void (*destr)(void *)}
Creates a \ctype{PyCObject} from the \code{void *} \var{cobj}. The
-\var{destr} function will be called when the object is reclaimed.
+\var{destr} function will be called when the object is reclaimed, unless
+it is \NULL.
\end{cfuncdesc}
\begin{cfuncdesc}{PyObject *}{PyCObject_FromVoidPtrAndDesc}{void* cobj,