diff --git a/lib/checknullpointer.cpp b/lib/checknullpointer.cpp
index 656cbb5a7..8cc92bb28 100644
--- a/lib/checknullpointer.cpp
+++ b/lib/checknullpointer.cpp
@@ -850,6 +850,9 @@ void CheckNullPointer::nullPointerByCheckAndDeRef()
                     else if (CheckNullPointer::isPointerDeRef(tok2, unknown))
                         nullPointerError(tok2, pointerName, linenr, inconclusive);
 
+                    else if (unknown && _settings->inconclusive)
+                        nullPointerError(tok2, pointerName, linenr, true);
+
                     else
                         break;
                 }
diff --git a/test/testnullpointer.cpp b/test/testnullpointer.cpp
index 8b2d9b555..abd2b8573 100644
--- a/test/testnullpointer.cpp
+++ b/test/testnullpointer.cpp
@@ -1370,6 +1370,19 @@ private:
               "    }\n"
               "}");
         ASSERT_EQUALS("", errout.str());
+
+        {
+            const char code[] = "void f(Fred *fred) {\n"
+                                "    if (fred == NULL) { }\n"
+                                "    fred->x();\n"
+                                "}";
+
+            check(code);    // non-inconclusive
+            ASSERT_EQUALS("", errout.str());
+
+            check(code, true);  // inconclusive
+            ASSERT_EQUALS("[test.cpp:3]: (error) Possible null pointer dereference: fred - otherwise it is redundant to check if fred is null at line 2\n", errout.str());
+        }
     }
 
     // Test CheckNullPointer::nullConstantDereference