From 3275119d1db551488fcf407a578e8a7a82714a76 Mon Sep 17 00:00:00 2001
From: Stinkfist0 <stinkfist0@gmail.com>
Date: Thu, 2 Mar 2017 16:12:20 +0200
Subject: [PATCH] TokenFunc::asStringRef: protect against null token.

---
 src/ifcparse/IfcParse.cpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/ifcparse/IfcParse.cpp b/src/ifcparse/IfcParse.cpp
index a43d9dc821..8c1f92a061 100644
--- a/src/ifcparse/IfcParse.cpp
+++ b/src/ifcparse/IfcParse.cpp
@@ -559,6 +559,9 @@ double TokenFunc::asFloat(const Token& t) {
 }
 
 const std::string &TokenFunc::asStringRef(const Token& t) {
+    if (t.type == Token_NONE) {
+        throw IfcParse::IfcException("Null token encountered, premature end of file?");
+    }
 	std::string &str = t.lexer->GetTempString();
 	t.lexer->TokenString(t.startPos, str);
 	if ((isString(t) || isEnumeration(t) || isBinary(t)) && !str.empty()) {