diff --git a/NEWS b/NEWS
index e98d823861f..cd75dca28fd 100644
--- a/NEWS
+++ b/NEWS
@@ -8,6 +8,7 @@ PHP                                                                        NEWS
     to complete the set; now possible thanks to bug #66015 being fixed. (Bob)
   . Fixed bug #66568 (Update reflection information for unserialize() function).
     (Ferenc)
+  . Fixed bug #66660 (Composer.phar install/update fails). (Ferenc)
 
 - mysqlnd:
   . Added a new fetching mode to mysqlnd. (Andrey)
diff --git a/Zend/tests/bug66660.phpt b/Zend/tests/bug66660.phpt
new file mode 100644
index 00000000000..9ae8a273367
--- /dev/null
+++ b/Zend/tests/bug66660.phpt
@@ -0,0 +1,13 @@
+--TEST--
+Bug #66660 (Composer.phar install/update fails)
+--STDIN--
+<?php __CLASS__ ?>
+--FILE--
+<?php
+file_put_contents(__DIR__."/bug66660.tmp.php", "<?php __CLASS__ ?>");
+echo php_strip_whitespace(__DIR__."/bug66660.tmp.php");
+?>
+--CLEAN--
+<?php unlink(__DIR__."/bug66660.tmp.php"); ?>
+--EXPECT--
+<?php __CLASS__ ?>
diff --git a/Zend/zend_highlight.c b/Zend/zend_highlight.c
index e4f8d0237a1..68f2b7b72dc 100644
--- a/Zend/zend_highlight.c
+++ b/Zend/zend_highlight.c
@@ -211,7 +211,7 @@ ZEND_API void zend_strip(TSRMLS_D)
 					break;
 
 				default:
-					efree(token.value.str.val);
+					STR_FREE(token.value.str.val);
 					break;
 			}
 		}