Fix PyGILState_GetThisThreadState() prototype in the API documentation.
diff --git a/Doc/c-api/init.rst b/Doc/c-api/init.rst
index 0c1c714..d78b43d 100644
--- a/Doc/c-api/init.rst
+++ b/Doc/c-api/init.rst
@@ -642,7 +642,7 @@
    .. versionadded:: 2.3
 
 
-.. c:function:: PyThreadState PyGILState_GetThisThreadState()
+.. c:function:: PyThreadState* PyGILState_GetThisThreadState()
 
    Get the current thread state for this thread.  May return ``NULL`` if no
    GILState API has been used on the current thread.  Note that the main thread