diff --git a/Examples/test-suite/preproc.i b/Examples/test-suite/preproc.i
index 4d5040dcb..ad0839fb3 100644
--- a/Examples/test-suite/preproc.i
+++ b/Examples/test-suite/preproc.i
@@ -266,7 +266,7 @@ inline const char* mangle ## #@__VA_ARGS__ () {
 #define THREE(FOO) 3
 
 #define one ONE
-#define two TWO
+#define two TWO()
 #define three THREE(42)
 
 
diff --git a/Examples/test-suite/python/preproc_runme.py b/Examples/test-suite/python/preproc_runme.py
index 3bf9ece09..c989294b6 100644
--- a/Examples/test-suite/python/preproc_runme.py
+++ b/Examples/test-suite/python/preproc_runme.py
@@ -8,3 +8,7 @@ if preproc.define != 1:
 
 if preproc.defined != 1:
   raise RuntimeError
+
+if 2*preproc.one != preproc.two:
+  raise RuntimeError
+
diff --git a/Source/Preprocessor/cpp.c b/Source/Preprocessor/cpp.c
index 414694059..070cfc3a5 100644
--- a/Source/Preprocessor/cpp.c
+++ b/Source/Preprocessor/cpp.c
@@ -618,7 +618,7 @@ expand_macro(String_or_char *name, List *args)
   }
 
   /* If the macro expects arguments, but none were supplied, we leave it in place */
-  if (!args && (margs)) {
+  if (!args && (margs) && Len(margs) > 0) {
     return NewString(name);
   }