diff --git a/ivl_target.h b/ivl_target.h
index dc56b9a7f..1d44f3a5c 100644
--- a/ivl_target.h
+++ b/ivl_target.h
@@ -41,6 +41,12 @@
 # define __attribute__(x)
 #endif
 
+#if defined(__cplusplus) && defined(_MSC_VER)
+# define ENUM_UNSIGNED_INT : unsigned int
+#else
+# define ENUM_UNSIGNED_INT
+#endif
+
 _BEGIN_DECL
 
 /*
@@ -201,11 +207,7 @@ typedef enum ivl_dis_domain_e {
       IVL_DIS_CONTINUOUS = 2
 } ivl_dis_domain_t;
 
-#if defined(__cplusplus) && !defined(__GNUC__)
-typedef enum ivl_drive_e : unsigned int {
-#else
-typedef enum ivl_drive_e {
-#endif
+typedef enum ivl_drive_e ENUM_UNSIGNED_INT {
       IVL_DR_HiZ    = 0,
       IVL_DR_SMALL  = 1,
       IVL_DR_MEDIUM = 2,
@@ -247,11 +249,7 @@ typedef enum ivl_expr_type_e {
       IVL_EX_UNARY = 14
 } ivl_expr_type_t;
 
-#if defined(__cplusplus) && !defined(__GNUC__)
-typedef enum ivl_select_type_e : unsigned int {
-#else
-typedef enum ivl_select_type_e {
-#endif
+typedef enum ivl_select_type_e ENUM_UNSIGNED_INT {
       IVL_SEL_OTHER = 0,
       IVL_SEL_IDX_UP = 1,
       IVL_SEL_IDX_DOWN = 2
@@ -353,11 +351,7 @@ typedef enum ivl_path_edge_e {
 
 /* Processes are initial, always, or final blocks with a statement. This is
    the type of the ivl_process_t object. */
-#if defined(__cplusplus) && !defined(__GNUC__)
-typedef enum ivl_process_type_e : unsigned int {
-#else
-typedef enum ivl_process_type_e {
-#endif
+typedef enum ivl_process_type_e ENUM_UNSIGNED_INT {
       IVL_PR_INITIAL = 0,
       IVL_PR_ALWAYS  = 1,
       IVL_PR_FINAL   = 2
@@ -443,11 +437,7 @@ typedef enum ivl_sfunc_as_task_e {
 
 /* This is the type of a variable, and also used as the type for an
    expression. */
-#if defined(__cplusplus) && !defined(__GNUC__)
-typedef enum ivl_variable_type_e : unsigned int {
-#else
-typedef enum ivl_variable_type_e {
-#endif
+typedef enum ivl_variable_type_e ENUM_UNSIGNED_INT {
       IVL_VT_VOID    = 0,  /* Not used */
       IVL_VT_NO_TYPE = 1,  /* Place holder for missing/unknown type. */
       IVL_VT_REAL    = 2,
@@ -2359,4 +2349,6 @@ typedef const char* (*target_query_f) (const char*key);
 
 _END_DECL
 
+#undef ENUM_UNSIGNED_INT
+
 #endif /* IVL_ivl_target_H */
diff --git a/netlist.h b/netlist.h
index 134f56f38..a3e601165 100644
--- a/netlist.h
+++ b/netlist.h
@@ -90,6 +90,12 @@ class netvector_t;
 struct target;
 struct functor_t;
 
+#if defined(__cplusplus) && defined(_MSC_VER)
+# define ENUM_UNSIGNED_INT : unsigned int
+#else
+# define ENUM_UNSIGNED_INT
+#endif
+
 ostream& operator << (ostream&o, ivl_variable_type_t val);
 
 extern void join_island(NetPins*obj);
@@ -102,12 +108,7 @@ class Link {
       friend class NexusSet;
 
     public:
-#if defined(__cplusplus) && !defined(__GNUC__)
-      enum DIR : unsigned int { PASSIVE, INPUT, OUTPUT };
-#else
-      enum DIR { PASSIVE, INPUT, OUTPUT };
-#endif
-
+      enum DIR ENUM_UNSIGNED_INT { PASSIVE, INPUT, OUTPUT };
     private: // Only NetPins can create/delete Link objects
       Link();
       ~Link();
@@ -623,11 +624,7 @@ class NetDelaySrc  : public NetObj {
 class PortType
 {
 public:
-#if defined(__cplusplus) && !defined(__GNUC__)
-	enum Enum : unsigned int { NOT_A_PORT, PIMPLICIT, PINPUT, POUTPUT, PINOUT, PREF };
-#else
-    enum Enum { NOT_A_PORT, PIMPLICIT, PINPUT, POUTPUT, PINOUT, PREF };
-#endif
+	enum Enum ENUM_UNSIGNED_INT { NOT_A_PORT, PIMPLICIT, PINPUT, POUTPUT, PINOUT, PREF };
 
     /*
      * Merge Port types (used to construct a sane combined port-type
@@ -655,11 +652,7 @@ struct PortInfo
 class NetNet  : public NetObj, public PortType {
 
     public:
-#if defined(__cplusplus) && !defined(__GNUC__)
-		enum Type : unsigned int { NONE, IMPLICIT, IMPLICIT_REG, INTEGER, WIRE, TRI, TRI1,
-#else
-      enum Type { NONE, IMPLICIT, IMPLICIT_REG, INTEGER, WIRE, TRI, TRI1,
-#endif
+      enum Type ENUM_UNSIGNED_INT { NONE, IMPLICIT, IMPLICIT_REG, INTEGER, WIRE, TRI, TRI1,
 		  SUPPLY0, SUPPLY1, WAND, TRIAND, TRI0, WOR, TRIOR, REG,
 		  UNRESOLVED_WIRE };
 
@@ -5017,4 +5010,5 @@ inline unsigned Link::get_pin() const
 	    return pin_;
 }
 
+#undef ENUM_UNSIGNED_INT
 #endif /* IVL_netlist_H */