Fixed #2586 (segmentation fault of cppcheck (template<>))

lib/tokenize.cpp

@@ -5528,6 +5528,9 @@ void Tokenizer::simplifyVarDecl()
                 }
             }
 
+            if (!tok2)
+                break;
+
             if (Token::Match(tok2, ":: %type%"))
             {
                 typelen += 2;

test/testtokenize.cpp

@@ -234,7 +234,8 @@ private:
         TEST_CASE(vardecl_union);
         TEST_CASE(volatile_variables);
         TEST_CASE(syntax_error);
-        TEST_CASE(syntax_error_templates);
+        TEST_CASE(syntax_error_templates_1);
+        TEST_CASE(syntax_error_templates_2);
 
         TEST_CASE(removeKeywords);
 
@@ -4165,7 +4166,7 @@ private:
     }
 
 
-    void syntax_error_templates()
+    void syntax_error_templates_1()
     {
         // ok code.. using ">" for a comparison
         {
@@ -4235,6 +4236,14 @@ private:
         }
     }
 
+    void syntax_error_templates_2()
+    {
+        std::istringstream istr("template<>\n");
+        Settings settings;
+        Tokenizer tokenizer(&settings, this);
+        tokenizer.tokenize(istr, "test.cpp");   // shouldn't segfault
+    }
+
     void removeKeywords()
     {
         const char code[] = "if (__builtin_expect(!!(x), 1));";