#6798: fix wrong docs for the arguments to several trace events.

Doc/c-api/init.rst

@@ -929,13 +929,14 @@ Python-level trace functions in previous versions.
    +------------------------------+--------------------------------------+
    | :const:`PyTrace_LINE`        | Always *NULL*.                       |
    +------------------------------+--------------------------------------+
-   | :const:`PyTrace_RETURN`      | Value being returned to the caller.  |
+   | :const:`PyTrace_RETURN`      | Value being returned to the caller,  |
+   |                              | or *NULL* if caused by an exception. |
    +------------------------------+--------------------------------------+
-   | :const:`PyTrace_C_CALL`      | Name of function being called.       |
+   | :const:`PyTrace_C_CALL`      | Function object being called.        |
    +------------------------------+--------------------------------------+
-   | :const:`PyTrace_C_EXCEPTION` | Always *NULL*.                       |
+   | :const:`PyTrace_C_EXCEPTION` | Function object being called.        |
    +------------------------------+--------------------------------------+
-   | :const:`PyTrace_C_RETURN`    | Always *NULL*.                       |
+   | :const:`PyTrace_C_RETURN`    | Function object being called.        |
    +------------------------------+--------------------------------------+
 
 

Doc/library/sys.rst

@@ -806,8 +806,9 @@ always available.
 
    ``'return'``
       A function (or other code block) is about to return.  The local trace
-      function is called; *arg* is the value that will be returned.  The trace
-      function's return value is ignored.
+      function is called; *arg* is the value that will be returned, or ``None``
+      if the event is caused by an exception being raised.  The trace function's
+      return value is ignored.
 
    ``'exception'``
       An exception has occurred.  The local trace function is called; *arg* is a
@@ -819,10 +820,10 @@ always available.
       a built-in.  *arg* is the C function object.
 
    ``'c_return'``
-      A C function has returned. *arg* is ``None``.
+      A C function has returned. *arg* is the C function object.
 
    ``'c_exception'``
-      A C function has raised an exception.  *arg* is ``None``.
+      A C function has raised an exception.  *arg* is the C function object.
 
    Note that as an exception is propagated down the chain of callers, an
    ``'exception'`` event is generated at each level.