diff -Pdpru mujs-1.2.0.orig/jsdump.c mujs-1.2.0/jsdump.c
--- mujs-1.2.0.orig/jsdump.c	2021-12-08 14:56:12.000000000 +0300
+++ mujs-1.2.0/jsdump.c	2022-05-18 18:37:44.522227643 +0300
@@ -682,11 +682,13 @@ static void pstmlist(int d, js_Ast *list
 void jsP_dumpsyntax(js_State *J, js_Ast *prog, int dominify)
 {
 	minify = dominify;
-	if (prog->type == AST_LIST)
-		pstmlist(-1, prog);
-	else {
-		pstm(0, prog);
-		nl();
+	if (prog) {
+		if (prog->type == AST_LIST)
+			pstmlist(-1, prog);
+		else {
+			pstm(0, prog);
+			nl();
+		}
 	}
 	if (minify > 1)
 		putchar('\n');
@@ -768,11 +770,13 @@ static void sblock(int d, js_Ast *list)
 void jsP_dumplist(js_State *J, js_Ast *prog)
 {
 	minify = 0;
-	if (prog->type == AST_LIST)
-		sblock(0, prog);
-	else
-		snode(0, prog);
-	nl();
+	if (prog) {
+		if (prog->type == AST_LIST)
+			sblock(0, prog);
+		else
+			snode(0, prog);
+		nl();
+	}
 }
 
 /* Compiled code */
diff -Pdpru mujs-1.2.0.orig/regexp.c mujs-1.2.0/regexp.c
--- mujs-1.2.0.orig/regexp.c	2021-12-08 14:56:12.000000000 +0300
+++ mujs-1.2.0/regexp.c	2022-05-18 18:32:24.114001044 +0300
@@ -622,25 +622,26 @@ struct Reinst {
 	Reinst *y;
 };
 
-static int count(struct cstate *g, Renode *node)
+static int count(struct cstate *g, Renode *node, int depth)
 {
 	int min, max, n;
 	if (!node) return 0;
+	if (++depth > REG_MAXREC) die(g, "stack overflow");
 	switch (node->type) {
 	default: return 1;
-	case P_CAT: return count(g, node->x) + count(g, node->y);
-	case P_ALT: return count(g, node->x) + count(g, node->y) + 2;
+	case P_CAT: return count(g, node->x, depth) + count(g, node->y, depth);
+	case P_ALT: return count(g, node->x, depth) + count(g, node->y, depth) + 2;
 	case P_REP:
 		min = node->m;
 		max = node->n;
-		if (min == max) n = count(g, node->x) * min;
-		else if (max < REPINF) n = count(g, node->x) * max + (max - min);
-		else n = count(g, node->x) * (min + 1) + 2;
+		if (min == max) n = count(g, node->x, depth) * min;
+		else if (max < REPINF) n = count(g, node->x, depth) * max + (max - min);
+		else n = count(g, node->x, depth) * (min + 1) + 2;
 		if (n < 0 || n > REG_MAXPROG) die(g, "program too large");
 		return n;
-	case P_PAR: return count(g, node->x) + 2;
-	case P_PLA: return count(g, node->x) + 2;
-	case P_NLA: return count(g, node->x) + 2;
+	case P_PAR: return count(g, node->x, depth) + 2;
+	case P_PLA: return count(g, node->x, depth) + 2;
+	case P_NLA: return count(g, node->x, depth) + 2;
 	}
 }
 
@@ -903,7 +904,7 @@ Reprog *regcompx(void *(*alloc)(void *ct
 	putchar('\n');
 #endif
 
-	n = 6 + count(&g, node);
+	n = 6 + count(&g, node, 0);
 	if (n < 0 || n > REG_MAXPROG)
 		die(&g, "program too large");