diff --git a/src/cc65/datatype.c b/src/cc65/datatype.c
index b69a44dd0..6d9afa403 100644
--- a/src/cc65/datatype.c
+++ b/src/cc65/datatype.c
@@ -1007,6 +1007,25 @@ const Type* PtrConversion (const Type* T)
 
 
 
+const Type* StdConversion (const Type* T)
+/* If the type is a function, convert it to pointer to function. If the
+** expression is an array, convert it to pointer to first element. If the
+** type is an integer, do integeral promotion. Otherwise return T.
+*/
+{
+    if (IsTypeFunc (T)) {
+        return AddressOf (T);
+    } else if (IsTypeArray (T)) {
+        return AddressOf (GetElementType (T));
+    } else if (IsClassInt (T)) {
+        return IntPromotion (T);
+    } else {
+        return T;
+    }
+}
+
+
+
 const Type* IntPromotion (const Type* T)
 /* Apply the integer promotions to T and return the result. The returned type
 ** string may be T if there is no need to change it.
diff --git a/src/cc65/datatype.h b/src/cc65/datatype.h
index c60023944..e8ba7b6c0 100644
--- a/src/cc65/datatype.h
+++ b/src/cc65/datatype.h
@@ -368,6 +368,12 @@ const Type* PtrConversion (const Type* T);
 ** return T.
 */
 
+const Type* StdConversion (const Type* T);
+/* If the type is a function, convert it to pointer to function. If the
+** expression is an array, convert it to pointer to first element. If the
+** type is an integer, do integeral promotion. Otherwise return T.
+*/
+
 const Type* IntPromotion (const Type* T);
 /* Apply the integer promotions to T and return the result. The returned type
 ** string may be T if there is no need to change it.
diff --git a/src/cc65/expr.c b/src/cc65/expr.c
index dc45b108d..dc2374190 100644
--- a/src/cc65/expr.c
+++ b/src/cc65/expr.c
@@ -765,9 +765,10 @@ static unsigned FunctionArgList (FuncDesc* Func, int IsFastcall, ExprDesc* ED)
             } else {
 
                 /* No prototype available. Convert array to "pointer to first
-                ** element", and function to "pointer to function".
+                ** element", function to "pointer to function" and do integral
+                ** promotion if necessary.
                 */
-                Expr.Type = PtrConversion (Expr.Type);
+                TypeConversion (&Expr, StdConversion (Expr.Type));
 
             }
 
@@ -3062,7 +3063,7 @@ static void parseadd (ExprDesc* Expr, int DoArrayRef)
             Error ("Invalid operands for binary operator '+'");
         } else {
             /* Array and function types must be converted to pointer types */
-            Expr->Type = PtrConversion (Expr->Type);
+            Expr->Type = StdConversion (Expr->Type);
         }
     }
 
@@ -3341,7 +3342,7 @@ static void parsesub (ExprDesc* Expr)
     }
 
     /* Result type is either a pointer or an integer */
-    Expr->Type = PtrConversion (Expr->Type);
+    Expr->Type = StdConversion (Expr->Type);
 
     /* Condition code not set */
     ED_MarkAsUntested (Expr);