diff --git a/.travis.yml b/.travis.yml
index 398a544..3e74fb1 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,15 +1,5 @@
 language: php
 
-php:
-# - 5.3 # requires old distro, see below
-  - 5.4
-  - 5.5
-  - 5.6
-  - 7.0
-  - 7.1
-  - 7.2
-  - hhvm # ignore errors, see below
-
 # lock distro so new future defaults will not break the build
 dist: trusty
 
@@ -17,8 +7,17 @@ matrix:
   include:
     - php: 5.3
       dist: precise
+    - php: 5.4
+    - php: 5.5
+    - php: 5.6
+    - php: 7.0
+    - php: 7.1
+    - php: 7.2
+    - php: 7.3
+    - php: 7.4
+    - php: hhvm-3.18
   allow_failures:
-    - php: hhvm
+    - php: hhvm-3.18
 
 install:
   - composer install --no-interaction
diff --git a/tests/FunctionAwaitAllTest.php b/tests/FunctionAwaitAllTest.php
index f445e77..2194ac2 100644
--- a/tests/FunctionAwaitAllTest.php
+++ b/tests/FunctionAwaitAllTest.php
@@ -115,6 +115,7 @@ public function testAwaitAllPendingPromiseWithTimeoutAndCancellerShouldNotCreate
         }
 
         gc_collect_cycles();
+        gc_collect_cycles(); // clear twice to avoid leftovers in PHP 7.4 with ext-xdebug and code coverage turned on
 
         $promise = new \React\Promise\Promise(function () { }, function () {
             throw new RuntimeException();