Handle reference zvals when outputting superglobals in phpinfo()

Fixes <https://bugs.php.net/80915>.

Closes GH-80915.

Signed-off-by: Christoph M. Becker <cmbecker69@gmx.de>

Author: IMSoP

NEWS

@@ -24,6 +24,10 @@ PHP                                                                        NEWS
   . Fixed bug #69668 (SOAP special XML characters in namespace URIs not
     encoded). (cmb)
 
+- Standard:
+  . Fixed bug #80915 (Taking a reference to $_SERVER hides its values from
+    phpinfo()). (Rowan Tommins)
+
 01 Apr 2021, PHP 7.4.17
 
 - Core:

ext/standard/info.c

@@ -176,7 +176,7 @@ static ZEND_COLD void php_print_gpcse_array(char *name, uint32_t name_length)
 	key = zend_string_init(name, name_length, 0);
 	zend_is_auto_global(key);
 
-	if ((data = zend_hash_find(&EG(symbol_table), key)) != NULL && (Z_TYPE_P(data) == IS_ARRAY)) {
+	if ((data = zend_hash_find_deref(&EG(symbol_table), key)) != NULL && (Z_TYPE_P(data) == IS_ARRAY)) {
 		ZEND_HASH_FOREACH_KEY_VAL(Z_ARRVAL_P(data), num_key, string_key, tmp) {
 			if (!sapi_module.phpinfo_as_text) {
 				php_info_print("<tr>");

ext/standard/tests/bug80915.phpt

@@ -0,0 +1,20 @@
+--TEST--
+Bug #80915: Taking a reference to $_SERVER hides its values from phpinfo()
+--FILE--
+<?php
+
+$_ENV = [];
+$_SERVER = [ 'test' => 'test' ];
+
+$reference =& $_SERVER;
+
+phpinfo(INFO_VARIABLES);
+
+?>
+--EXPECT--
+phpinfo()
+
+PHP Variables
+
+Variable => Value
+$_SERVER['test'] => test