From f6c6217804189b406a2daca718e3b4464e25e302 Mon Sep 17 00:00:00 2001
From: parrt <parrt@cs.usfca.edu>
Date: Fri, 9 Nov 2018 11:31:59 -0800
Subject: [PATCH] Force usage of previousContext in Cpp

---
 tool/resources/org/antlr/v4/tool/templates/codegen/Cpp/Cpp.stg | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tool/resources/org/antlr/v4/tool/templates/codegen/Cpp/Cpp.stg b/tool/resources/org/antlr/v4/tool/templates/codegen/Cpp/Cpp.stg
index 68957f1b8..4c367dda5 100644
--- a/tool/resources/org/antlr/v4/tool/templates/codegen/Cpp/Cpp.stg
+++ b/tool/resources/org/antlr/v4/tool/templates/codegen/Cpp/Cpp.stg
@@ -510,6 +510,7 @@ LeftRecursiveRuleFunction(currentRule, args, code, locals, ruleCtx, altLabelCtxs
   size_t parentState = getState();
   <parser.name>::<currentRule.ctxType> *_localctx = _tracker.createInstance\<<currentRule.ctxType>\>(_ctx, parentState<currentRule.args: {a | , <a.name>}>);
   <parser.name>::<currentRule.ctxType> *previousContext = _localctx;
+  (void)previousContext; // Silence compiler, in case the context is not used by generated code.
   size_t startState = <currentRule.startState>;
   enterRecursionRule(_localctx, <currentRule.startState>, <parser.name>::Rule<currentRule.name; format = "cap">, precedence);