I added some code to help with constants but it's not working.

src/intermediate_code.h

@@ -35,6 +35,30 @@ typedef enum {
 
 
 } Op;
+
+typedef enum {
+        NODE,
+        INTEGER,
+        STRING,
+        CHARACTER,
+        ADDRESS,
+        BOOLEAN
+} Discriminant;
+
+typedef union {
+        TableNode *     node;
+        int             integer;
+        char *          string;
+        char            character;
+        void *          address;
+        bool            Boolean;
+} Register_union;
+
+typedef struct {
+        Discriminant d;
+        Register_union r_union;
+} TNodeOrConst;
+
 typedef struct Instruction {
         Op opcode;
         TableNode * result;