diff --git a/src/Psalm/Checker/ClassLikeChecker.php b/src/Psalm/Checker/ClassLikeChecker.php
index b2d044559..33c88b372 100644
--- a/src/Psalm/Checker/ClassLikeChecker.php
+++ b/src/Psalm/Checker/ClassLikeChecker.php
@@ -603,6 +603,11 @@ abstract class ClassLikeChecker extends SourceChecker implements StatementsSourc
             return false;
         }
 
+        // if we don't care the parent class does not exist, exit now.
+        if (!ClassLikeChecker::classOrInterfaceExists($parent_class, $this->getFileChecker())) {
+            return;
+        }
+
         self::$class_extends[$this->fq_class_name] = self::$class_extends[$this->parent_fq_class_name];
         self::$class_extends[$this->fq_class_name][$this->parent_fq_class_name] = true;
 
diff --git a/tests/ClassTest.php b/tests/ClassTest.php
index e8531acfe..08d0e7a2e 100644
--- a/tests/ClassTest.php
+++ b/tests/ClassTest.php
@@ -21,8 +21,6 @@ class ClassTest extends PHPUnit_Framework_TestCase
     public static function setUpBeforeClass()
     {
         self::$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
-
-        $config = new TestConfig();
     }
 
     /**
@@ -30,6 +28,7 @@ class ClassTest extends PHPUnit_Framework_TestCase
      */
     public function setUp()
     {
+        $config = new TestConfig();
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
     }
@@ -532,4 +531,39 @@ class ClassTest extends PHPUnit_Framework_TestCase
         $context = new Context();
         $file_checker->visitAndAnalyzeMethods($context);
     }
+
+    /**
+     * @expectedException        \Psalm\Exception\CodeException
+     * @expectedExceptionMessage UndefinedClass
+     * @return                   void
+     */
+    public function testMissingParent()
+    {
+        $stmts = self::$parser->parse('<?php
+        class A extends B { }
+        ');
+
+        $file_checker = new FileChecker('somefile.php', $this->project_checker, $stmts);
+        $context = new Context();
+        $file_checker->visitAndAnalyzeMethods($context);
+    }
+
+    /**
+     * @return void
+     */
+    public function testMissingParentWithFunction()
+    {
+        Config::getInstance()->setCustomErrorLevel('UndefinedClass', Config::REPORT_SUPPRESS);
+
+        $stmts = self::$parser->parse('<?php
+        class A extends B {
+            /** @return void */
+            public function foo() { }
+        }
+        ');
+
+        $file_checker = new FileChecker('somefile.php', $this->project_checker, $stmts);
+        $context = new Context();
+        $file_checker->visitAndAnalyzeMethods($context);
+    }
 }