diff --git a/src/cc65/declare.c b/src/cc65/declare.c
index d16a095a3..09a3f0020 100644
--- a/src/cc65/declare.c
+++ b/src/cc65/declare.c
@@ -507,7 +507,7 @@ static SymEntry* ParseStructDecl (const char* Name, TypeCode StructType)
             }
 
 	    /* Get type and name of the struct field */
-	    ParseDecl (&Spec, &Decl, 0);
+	    ParseDecl (&Spec, &Decl, DM_NEED_IDENT);
 
             /* Get the offset of this field */
             Offs = (StructType == T_STRUCT)? StructSize : 0;
@@ -1049,7 +1049,7 @@ static FuncDesc* ParseFuncDecl (void)
 
 
 
-static void Declarator (const DeclSpec* Spec, Declaration* D, unsigned Mode)
+static void Declarator (const DeclSpec* Spec, Declaration* D, declmode_t Mode)
 /* Recursively process declarators. Build a type array in reverse order. */
 {
     /* Read optional function or pointer qualifiers. These modify the
@@ -1213,7 +1213,7 @@ Type* ParseType (Type* T)
 
 
 
-void ParseDecl (const DeclSpec* Spec, Declaration* D, unsigned Mode)
+void ParseDecl (const DeclSpec* Spec, Declaration* D, declmode_t Mode)
 /* Parse a variable, type or function declaration */
 {
     /* Initialize the Declaration struct */
diff --git a/src/cc65/declare.h b/src/cc65/declare.h
index fb510ef30..eac2897d9 100644
--- a/src/cc65/declare.h
+++ b/src/cc65/declare.h
@@ -75,9 +75,11 @@ struct Declaration {
 };
 
 /* Modes for ParseDecl */
-#define DM_NEED_IDENT	0U		/* We must have an identifier */
-#define DM_NO_IDENT	1U		/* We won't read an identifier */
-#define DM_ACCEPT_IDENT	2U		/* We will accept an id if there is one */
+typedef enum {                                                   
+    DM_NEED_IDENT,                      /* We must have an identifier */
+    DM_NO_IDENT,                        /* We won't read an identifier */
+    DM_ACCEPT_IDENT,                    /* We will accept an id if there is one */
+} declmode_t;
 
 
 
@@ -90,7 +92,7 @@ struct Declaration {
 Type* ParseType (Type* Type);
 /* Parse a complete type specification */
 
-void ParseDecl (const DeclSpec* Spec, Declaration* D, unsigned Mode);
+void ParseDecl (const DeclSpec* Spec, Declaration* D, declmode_t Mode);
 /* Parse a variable, type or function declaration */
 
 void ParseDeclSpec (DeclSpec* D, unsigned DefStorage, long DefType);