From 90db64dcde22364704f0af82641ede2edb6f3373 Mon Sep 17 00:00:00 2001
From: yeti0904 <mesyeti@mesyeti.uk>
Date: Fri, 17 Nov 2023 20:32:04 +0000
Subject: [PATCH] fix assembler crashing when labels aren't found

---
 source/assembler/assembler.d | 17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/source/assembler/assembler.d b/source/assembler/assembler.d
index e908841..ed280a6 100644
--- a/source/assembler/assembler.d
+++ b/source/assembler/assembler.d
@@ -392,12 +392,10 @@ class Assembler {
 					}
 
 					if (!valid) {
-						Error(
-							format(
-								"Parameter %d is invalid for instruction %s", i + 1,
-								inst.name
-							)
-						);
+						Error(format(
+							"Parameter %d is invalid for instruction %s", i + 1,
+							inst.name
+						));
 						exit(1);
 					}
 				}
@@ -448,6 +446,13 @@ class Assembler {
 								case NodeType.Identifier: {
 									auto paramNode = cast(IdentifierNode) param;
 
+									if (paramNode.name !in labels) {
+										Error(format(
+											"No such label: '%s'", paramNode.name
+										));
+										return;
+									}
+
 									addr = labels[paramNode.name];
 
 									string[] bsInstructions = [