Update pb_release docs

diff --git a/docs/reference.rst b/docs/reference.rst
index be6567e..6968c81 100644 (file)
--- a/docs/reference.rst
+++ b/docs/reference.rst
@@ -630,10 +630,10 @@ pb_release
 ----------
 Releases any dynamically allocated fields.
 
-    void pb_release(const pb_field_t fields[], void *dest_struct);
+    void pb_release(const pb_field_t fields[], void \*dest_struct);
 
 :fields:        A field description array. Usually autogenerated.
-:dest_struct:   Pointer to structure where data will be stored.
+:dest_struct:   Pointer to structure where data is stored. If NULL, function does nothing.
 
 This function is only available if *PB_ENABLE_MALLOC* is defined. It will release any
 pointer type fields in the structure and set the pointers to NULL.