From 56544ac936809ffcfe223c232a81695cf8fa4338 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Marjam=C3=A4ki?= <daniel.marjamaki@gmail.com>
Date: Mon, 11 Sep 2017 13:45:36 +0200
Subject: [PATCH] Fixed #8211 (Crash on incomplete code in isVariableChanged
 ())

---
 lib/astutils.cpp      |  2 +-
 test/testastutils.cpp | 20 ++++++++++++++++++++
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/lib/astutils.cpp b/lib/astutils.cpp
index 1cbb20ed5..2257db68a 100644
--- a/lib/astutils.cpp
+++ b/lib/astutils.cpp
@@ -457,7 +457,7 @@ bool isVariableChanged(const Token *start, const Token *end, const unsigned int
             if (Token::simpleMatch(shr->astParent(), ">>"))
                 return true;
             const Token *lhs = shr->astOperand1();
-            if (!lhs->valueType() || !lhs->valueType()->isIntegral())
+            if (!lhs || !lhs->valueType() || !lhs->valueType()->isIntegral())
                 return true;
         }
 
diff --git a/test/testastutils.cpp b/test/testastutils.cpp
index 2fb6ef3e3..db3046086 100644
--- a/test/testastutils.cpp
+++ b/test/testastutils.cpp
@@ -34,6 +34,7 @@ private:
 
     void run() {
         TEST_CASE(isReturnScope);
+        TEST_CASE(isVariableChanged);
     }
 
     bool isReturnScope(const char code[], int offset) {
@@ -54,6 +55,25 @@ private:
         ASSERT_EQUALS(true, isReturnScope("void f() { if (a) { {throw new string(x);}; } }", -4)); // #7144
         ASSERT_EQUALS(true, isReturnScope("void f() { if (a) { {throw new string(x);}; } }", -2)); // #7144
     }
+
+    bool isVariableChanged(const char code[], const char startPattern[], const char endPattern[]) {
+        Settings settings;
+        Tokenizer tokenizer(&settings, this);
+        std::istringstream istr(code);
+        tokenizer.tokenize(istr, "test.cpp");
+        const Token * const tok1 = Token::findsimplematch(tokenizer.tokens(), startPattern);
+        const Token * const tok2 = Token::findsimplematch(tokenizer.tokens(), endPattern);
+        return ::isVariableChanged(tok1,tok2,1,false,&settings);
+    }
+
+    void isVariableChanged() {
+		// #8211 - no lhs for >> , do not crash
+        ASSERT_EQUALS(true,
+                      isVariableChanged("void f() {\n"
+                                        "  int b;\n"
+                                        "  if (b) { (int)((INTOF(8))result >> b); }\n"
+                                        "}", "if", "}"));
+    }
 };
 
 REGISTER_TEST(TestAstUtils)