diff --git a/std/haxe/math/bigint/BigIntArithmetic.hx b/std/haxe/math/bigint/BigIntArithmetic.hx
index 60eed8b61fc..013abcf6e1c 100644
--- a/std/haxe/math/bigint/BigIntArithmetic.hx
+++ b/std/haxe/math/bigint/BigIntArithmetic.hx
@@ -54,8 +54,12 @@ class BigIntArithmetic {
 		returns 0 (`a == b`).
 	**/
 	public static function compare(a6:BigInt_, b:BigInt_):Int {
+		#if lua
 		trace("______________Compare(b):  "+b);
 		trace("______________Compare(a):  "+a6);
+		if (a6 == null)
+			haxe.CallStack.toString(haxe.CallStack.exceptionStack());
+		#end
 		if (a6 != b) {
 			var c:Int = (a6.sign() & 2) + (b.sign() & 1);
 			switch (c) {
diff --git a/std/haxe/math/bigint/BigInt_.hx b/std/haxe/math/bigint/BigInt_.hx
index a59b6a0aa87..df159ab2f07 100644
--- a/std/haxe/math/bigint/BigInt_.hx
+++ b/std/haxe/math/bigint/BigInt_.hx
@@ -647,6 +647,9 @@ class BigInt_ {
 		
 		do {
 			do {
+				#if lua
+				trace("bitLength: "+this.bitLength());
+				#end
 				num = random(this.bitLength());
 				#if lua
 				trace("num: "+num);