diff --git a/Doc/c-api/tuple.rst b/Doc/c-api/tuple.rst
index cf1c7902828..53db2a18398 100644
--- a/Doc/c-api/tuple.rst
+++ b/Doc/c-api/tuple.rst
@@ -74,6 +74,10 @@ Tuple Objects
    Return the size of the tuple *p*, which must be non-*NULL* and point to a tuple;
    no error checking is performed.
 
+   .. versionchanged:: 2.5
+      This function returned an :ctype:`int` type. This might require changes
+      in your code for properly supporting 64-bit systems.
+
 
 .. cfunction:: PyObject* PyTuple_GetItem(PyObject *p, Py_ssize_t pos)
 
@@ -89,6 +93,10 @@ Tuple Objects
 
    Like :cfunc:`PyTuple_GetItem`, but does no checking of its arguments.
 
+   .. versionchanged:: 2.5
+      This function used an :ctype:`int` type for *pos*. This might require
+      changes in your code for properly supporting 64-bit systems.
+
 
 .. cfunction:: PyObject* PyTuple_GetSlice(PyObject *p, Py_ssize_t low, Py_ssize_t high)
 
@@ -123,6 +131,10 @@ Tuple Objects
 
       This function "steals" a reference to *o*.
 
+   .. versionchanged:: 2.5
+      This function used an :ctype:`int` type for *pos*. This might require
+      changes in your code for properly supporting 64-bit systems.
+
 
 .. cfunction:: int _PyTuple_Resize(PyObject **p, Py_ssize_t newsize)