From 632c42ca1086f48eeabafb4b64597719795a5d46 Mon Sep 17 00:00:00 2001
From: Mikhalkovich Stanislav <miks@math.sfedu.ru>
Date: Mon, 1 Apr 2019 07:25:01 +0300
Subject: [PATCH] fix #1897

---
 SyntaxTree/tree/TreeHelper.cs                       |  5 +++++
 TestSuite/errors/err0317.pas                        |  3 +++
 TestSuite/loopn.pas                                 | 10 ++++++++++
 TreeConverter/TreeConversion/syntax_tree_visitor.cs |  3 +++
 4 files changed, 21 insertions(+)
 create mode 100644 TestSuite/errors/err0317.pas
 create mode 100644 TestSuite/loopn.pas

diff --git a/SyntaxTree/tree/TreeHelper.cs b/SyntaxTree/tree/TreeHelper.cs
index 9cd04e29b..33bcd06e4 100644
--- a/SyntaxTree/tree/TreeHelper.cs
+++ b/SyntaxTree/tree/TreeHelper.cs
@@ -1836,5 +1836,10 @@ namespace PascalABCCompiler.SyntaxTree
         }
     }
 
+    public partial class semantic_check_sugared_statement_node
+    {
+        public bool visited = false;
+    }
+
     }
 
diff --git a/TestSuite/errors/err0317.pas b/TestSuite/errors/err0317.pas
new file mode 100644
index 000000000..9e1cbf4fc
--- /dev/null
+++ b/TestSuite/errors/err0317.pas
@@ -0,0 +1,3 @@
+begin
+  Writeln(1 mod 0);
+end.
\ No newline at end of file
diff --git a/TestSuite/loopn.pas b/TestSuite/loopn.pas
new file mode 100644
index 000000000..5dc0438c8
--- /dev/null
+++ b/TestSuite/loopn.pas
@@ -0,0 +1,10 @@
+begin
+  var n := 10;
+  loop n do
+    Print(1);
+  var p: procedure;
+  p := ()->begin
+    Print(n);
+  end;
+  Assert(1=1);
+end.
\ No newline at end of file
diff --git a/TreeConverter/TreeConversion/syntax_tree_visitor.cs b/TreeConverter/TreeConversion/syntax_tree_visitor.cs
index 217a3af6b..0fd3849aa 100644
--- a/TreeConverter/TreeConversion/syntax_tree_visitor.cs
+++ b/TreeConverter/TreeConversion/syntax_tree_visitor.cs
@@ -20111,6 +20111,9 @@ namespace PascalABCCompiler.TreeConverter
 
         public override void visit(SyntaxTree.semantic_check_sugared_statement_node st)
         {
+            if (st.visited)
+                return;
+            st.visited = true;
             if (st.typ as System.Type == typeof(SyntaxTree.assign_tuple))
             {
                 var vars = st.lst[0] as SyntaxTree.addressed_value_list;