Fixed #1640 (False negative: Unused value (variable is assigned but never read))

lib/checkother.cpp

@@ -809,9 +809,12 @@ static int doAssignment(Variables &variables, const Token *tok, bool pointer)
             }
             else // not a local variable
             {
-                // aliased variables in a larger scope are not supported yet
-                if (varid2)
-                    variables.erase(varid1);
+                if (var1->_type == Variables::pointer && !pointer)
+                {
+                    // aliased variables in a larger scope are not supported yet
+                    if (varid2)
+                        variables.erase(varid1);
+                }
             }
         }
     }

test/testunusedvar.cpp

@@ -75,6 +75,7 @@ private:
         TEST_CASE(localvar10);
         TEST_CASE(localvar11);
         TEST_CASE(localvar12);
+        TEST_CASE(localvar13); // ticket #1640
         TEST_CASE(localvaralias1);
         TEST_CASE(localvaralias2); // ticket #1637
         TEST_CASE(localvarasm);
@@ -1039,6 +1040,16 @@ private:
             errout.str());
     }
 
+    void localvar13() // ticket #1640
+    {
+        functionVariableUsage("void foo( OBJECT *obj )\n"
+                              "{\n"
+                              "    int x;\n"
+                              "    x = obj->ySize / 8;\n"
+                              "}\n");
+        ASSERT_EQUALS("[test.cpp:3]: (style) Variable 'x' is assigned a value that is never used\n", errout.str());
+    }
+
     void localvaralias1()
     {
         functionVariableUsage("void foo()\n"