diff --git a/ext/opcache/tests/bug78106.phpt b/ext/opcache/tests/bug78106.phpt
new file mode 100644
index 00000000000..86c8acd3ae1
--- /dev/null
+++ b/ext/opcache/tests/bug78106.phpt
@@ -0,0 +1,22 @@
+--TEST--
+Bug #78106: PHP Fatal error: Uncaught Error: Class 'Phpfastcache\Config\Config' not found
+--XFAIL--
+Not fixed yet
+--FILE--
+<?php
+
+include __DIR__ . "/php_cli_server.inc";
+php_cli_server_start(getenv('TEST_PHP_EXTRA_ARGS'));
+
+echo file_get_contents("http://" . PHP_CLI_SERVER_ADDRESS . "/bug78106_test1.php" );
+echo file_get_contents("http://" . PHP_CLI_SERVER_ADDRESS . "/bug78106_test2.php" );
+echo file_get_contents("http://" . PHP_CLI_SERVER_ADDRESS . "/bug78106_test1.php" );
+
+?>
+--EXPECT--
+included
+done
+included
+done
+included
+done
diff --git a/ext/opcache/tests/bug78106_include.inc b/ext/opcache/tests/bug78106_include.inc
new file mode 100644
index 00000000000..06e39270f69
--- /dev/null
+++ b/ext/opcache/tests/bug78106_include.inc
@@ -0,0 +1,3 @@
+<?php
+
+echo "included\n";
diff --git a/ext/opcache/tests/bug78106_test1.php b/ext/opcache/tests/bug78106_test1.php
new file mode 100644
index 00000000000..85216d4b92b
--- /dev/null
+++ b/ext/opcache/tests/bug78106_test1.php
@@ -0,0 +1,6 @@
+<?php
+
+ini_set('opcache.enable', 0);
+require_once 'bug78106_include.inc';
+
+echo "done\n";
diff --git a/ext/opcache/tests/bug78106_test2.php b/ext/opcache/tests/bug78106_test2.php
new file mode 100644
index 00000000000..6a6aa755358
--- /dev/null
+++ b/ext/opcache/tests/bug78106_test2.php
@@ -0,0 +1,5 @@
+<?php
+
+require_once 'bug78106_include.inc';
+
+echo "done\n";
diff --git a/run-tests.php b/run-tests.php
index 1e075095060..d5638aad996 100755
--- a/run-tests.php
+++ b/run-tests.php
@@ -820,7 +820,7 @@ HELP;
 		if (substr(PHP_OS, 0, 3) == "WIN") {
 			$pass_options .= " -c " . escapeshellarg($conf_passed);
 		} else {
-			$pass_options .= " -c '$conf_passed'";
+			$pass_options .= " -c '" . realpath($conf_passed) . "'";
 		}
 	}
 
@@ -1611,6 +1611,8 @@ TEST $file
 
 	settings2params($ini_settings);
 
+	$env['TEST_PHP_EXTRA_ARGS'] = $pass_options . ' ' . $ini_settings;
+
 	// Check if test should be skipped.
 	$info = '';
 	$warn = false;