diff --git a/h/cgg_cg.h b/h/cgg_cg.h
index acc29f4ed..b4f00a5f3 100644
--- a/h/cgg_cg.h
+++ b/h/cgg_cg.h
@@ -38,6 +38,7 @@
 #define DO_SETCC	22
 #define DO_TOSTACK	23
 #define DO_KILLREG	24
+#define DO_LABDEF	25
 
 #ifndef MAXATT
 #define MAXATT TOKENSIZE
@@ -130,6 +131,8 @@ typedef struct exprnode *node_p;
 #define EX_XOR		42
 #define EX_AND		43
 #define EX_ISROM	44
+#define EX_STACKHEIGHT	45
+#define EX_FALLTHROUGH	46
 
 
 typedef struct {        /* to stack coercions */
diff --git a/h/em_mes.h b/h/em_mes.h
index a634b67f0..e5c4862d7 100644
--- a/h/em_mes.h
+++ b/h/em_mes.h
@@ -21,6 +21,7 @@
 #define ms_gto	11	/* Dangerous procedure, uses nonlocal goto	     */
 #define ms_stb	12	/* symbol table entry (for debugger)		     */
 #define ms_lin	13	/* line number indication (for debugger symbol table)*/
+#define ms_sth  14      /* Height of the stack at a certain label	     */
 
 /*
  * for details about ms_reg, see em_reg.h