My last fix for left recursion detection didn't worked for any depth,…

… this now seems to work in all cases

src/Tab.cpp

@@ -893,25 +893,25 @@ bool Tab::GrammarCheckAll() {
         int errors = 0;
         if(!NtsComplete()) ++errors;
         if(!AllNtReached()) ++errors;
-        if(!NoCircularProductions()) ++errors;
+        if(!NoCircularProductions()) exit(1);
         if(!AllNtToTerm()) ++errors;
         CheckResolvers(); CheckLL1();
         return errors == 0;
 }
 
 //--------------- check for circular productions ----------------------
 
-void Tab::GetSingles(const Node *p, TArrayList<Symbol*> &singles, const Node *rule) {
+void Tab::GetSingles(const Node *p, TArrayList<Symbol*> &singles) {
 	if (p == NULL) return;  // end of graph
 	if (p->typ == Node::nt) {
-		if (p->up || DelGraph(p->next) || p->sym->graph == rule) singles.Add(p->sym);
+                singles.Add(p->sym);
 	} else if (p->typ == Node::alt || p->typ == Node::iter || p->typ == Node::opt) {
 		if (p->up || DelGraph(p->next)) {
-			GetSingles(p->sub, singles, rule);
-			if (p->typ == Node::alt) GetSingles(p->down, singles, rule);
+			GetSingles(p->sub, singles);
+			if (p->typ == Node::alt) GetSingles(p->down, singles);
 		}
 	}
-	if (!p->up && DelNode(p)) GetSingles(p->next, singles, rule);
+	if (!p->up && DelNode(p)) GetSingles(p->next, singles);
 }
 
 bool Tab::NoCircularProductions() {
@@ -924,7 +924,7 @@ bool Tab::NoCircularProductions() {
 	for (i=0; i<nonterminals.Count; i++) {
 		sym = nonterminals[i];
 		TArrayList<Symbol*> singles;
-		GetSingles(sym->graph, singles, sym->graph); // get nonterminals s such that sym-->s
+		GetSingles(sym->graph, singles); // get nonterminals s such that sym-->s
 		Symbol *s;
 		for (int j=0; j<singles.Count; j++) {
 			s = singles[j];
@@ -955,7 +955,7 @@ bool Tab::NoCircularProductions() {
 	for (i=0; i<list.Count; i++) {
 		n = list[i];
 			ok = false; errors->count++;
-		wprintf(_SC("  %") _SFMT _SC(" --> %") _SFMT, n->left->name, n->right->name);
+		wprintf(_SC("  %") _SFMT _SC(":%d --> %") _SFMT _SC(":%d\n"), n->left->name, n->left->line, n->right->name, n->right->line);
 	}
         for(int i=0; i<list.Count; ++i) delete list[i];
 	return ok;

src/Tab.h

@@ -197,7 +197,7 @@ class Tab {
 		}
 	};
 
-	void GetSingles(const Node *p, TArrayList<Symbol*> &singles, const Node *rule);
+	void GetSingles(const Node *p, TArrayList<Symbol*> &singles);
 	bool NoCircularProductions();
 
 	//--------------- check for LL(1) errors ----------------------

src/TestSuite/TestCircular_Output.txt

@@ -1,5 +1,8 @@
 Coco/R (Dec 01, 2018)
 checking
   D deletable
-  A --> B  B --> C  C --> Atrace output is in trace.txt
+  A:21 --> B:22
+  B:22 --> C:23
+  C:23 --> A:21
+trace output is in trace.txt
 3 errors detected