Origin: upstream, http://git.ghostscript.com/?p=mujs.git;a=commit;h=f5b3c703e18725e380b83427004632e744f85a6f
From: Tor Andersson <tor.andersson@artifex.com>
Date: Tue, 17 May 2022 15:57:00 +0200
Subject: Issue #161: Cope with empty programs in mujs-pp.

---
 jsdump.c | 24 ++++++++++++++----------
 1 file changed, 14 insertions(+), 10 deletions(-)

diff --git a/jsdump.c b/jsdump.c
index 86361e6..42c9f0f 100644
--- a/jsdump.c
+++ b/jsdump.c
@@ -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 */