Index: docs/LangRef.rst
===================================================================
--- docs/LangRef.rst
+++ docs/LangRef.rst
@@ -9047,9 +9047,10 @@
    - The calling conventions of the caller and callee must match.
    - All ABI-impacting function attributes, such as sret, byval, inreg,
      returned, and inalloca, must match.
-   - The callee must be varargs iff the caller is varargs. Bitcasting a
-     non-varargs function to the appropriate varargs type is legal so
-     long as the non-varargs prefixes obey the other rules.
+   - The callee must be varargs iff the caller is varargs. If the callee is
+     varargs, the varargs passed to the caller will get passed to the callee
+     too. Bitcasting a non-varargs function to the appropriate varargs type is
+     legal so long as the non-varargs prefixes obey the other rules.
 
    Tail call optimization for calls marked ``tail`` is guaranteed to occur if
    the following conditions are met: