diff --git a/Zend/tests/gh16665_1.phpt b/Zend/tests/gh16665_1.phpt
new file mode 100644
index 0000000000000..5baa46a039121
--- /dev/null
+++ b/Zend/tests/gh16665_1.phpt
@@ -0,0 +1,8 @@
+--TEST--
+GH-16665 (\array should not be usable)
+--FILE--
+<?php
+class_alias('stdClass', 'array');
+?>
+--EXPECTF--
+Fatal error: Cannot use "array" as a class alias as it is reserved in %s on line %d
diff --git a/Zend/tests/gh16665_2.phpt b/Zend/tests/gh16665_2.phpt
new file mode 100644
index 0000000000000..3b8ffd4c1e6b0
--- /dev/null
+++ b/Zend/tests/gh16665_2.phpt
@@ -0,0 +1,8 @@
+--TEST--
+GH-16665 (\callable should not be usable)
+--FILE--
+<?php
+class_alias('stdClass', 'callable');
+?>
+--EXPECTF--
+Fatal error: Cannot use "callable" as a class alias as it is reserved in %s on line %d
diff --git a/Zend/zend_compile.c b/Zend/zend_compile.c
index 73bc661cd40e3..ce8fa88dee3c0 100644
--- a/Zend/zend_compile.c
+++ b/Zend/zend_compile.c
@@ -214,6 +214,10 @@ static const struct reserved_class_name reserved_class_names[] = {
 	{ZEND_STRL("iterable")},
 	{ZEND_STRL("object")},
 	{ZEND_STRL("mixed")},
+	/* These are not usable as class names because they're proper tokens,
+	 * but they are here for class aliases. */
+	{ZEND_STRL("array")},
+	{ZEND_STRL("callable")},
 	{NULL, 0}
 };