Merge branch 'PHP-7.1' into PHP-7.2

* PHP-7.1:
  Fix bug #76524 - ZipArchive memory leak

Author: weltling

ext/zip/php_zip.c

@@ -1026,10 +1026,13 @@ static void php_zip_object_free_storage(zend_object *object) /* {{{ */
 	}
 	if (intern->za) {
 		if (zip_close(intern->za) != 0) {
+#if LIBZIP_VERSION_MAJOR == 1 && LIBZIP_VERSION_MINOR == 3 && LIBZIP_VERSION_MICRO == 1
+			php_error_docref(NULL, E_WARNING, "Cannot destroy the zip context: %s", "zip_close have failed");
+#else
 			php_error_docref(NULL, E_WARNING, "Cannot destroy the zip context: %s", zip_strerror(intern->za));
-			return;
+			zip_discard(intern->za);
+#endif
 		}
-		intern->za = NULL;
 	}
 
 	if (intern->buffers_cnt>0) {

ext/zip/tests/bug76524.phpt

@@ -0,0 +1,21 @@
+--TEST--
+ZipArchive Bug #76524 (memory leak with ZipArchive::OVERWRITE flag and empty archive)
+--SKIPIF--
+<?php
+if(!extension_loaded('zip')) die('skip');
+?>
+--FILE--
+<?php
+
+$filename = __DIR__ . '/nonexistent.zip';
+
+$zip = new ZipArchive();
+$zip->open($filename, ZipArchive::CREATE | ZipArchive::OVERWRITE);
+echo 'ok';
+
+/* Zip-related error messages depend on platform and libzip version,
+   so the regex is used to check that Zend MM does NOT show warnings
+   about leaks: */
+?>
+--EXPECTREGEX--
+ok((?!memory leaks detected).)*