...

src/compiler/Generation/QBE/QBEGenerator.cs

@@ -458,6 +458,8 @@ public static class QBEGenerator
     {
         _variables.Clear();
         _variableScopes.Clear();
+        _variableIndex = 0;
+        _labelIndex = 0;
 
         var builder = new StringBuilder();
 

src/compiler/Generation/QBE/QBEWriter.cs

@@ -31,9 +31,6 @@ public class QBEWriter
 
     private void WriteDebugLocation(SourceSpan span)
     {
-        if (span.IsEmpty)
-            return;
-
         var line = span.Start.Line;
 
         if (_currentLine != line)