From bc21d161e8b37411c8789687d454a8f55e54c538 Mon Sep 17 00:00:00 2001
From: Niels Dossche <7771979+nielsdos@users.noreply.github.com>
Date: Mon, 23 Jan 2023 22:11:08 +0100
Subject: [PATCH] Fix incorrect page_size check

The current check always evaluated to false because if `!page_size`
is true, then `page_size & (page_size - 1)` equals `0 & (0 - 1)` which
is always 0. The if condition is meant to check if page_size is zero or
not a power of two, thus we must change the AND to an OR to fix this
issue.
---
 ext/opcache/ZendAccelerator.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/ext/opcache/ZendAccelerator.c b/ext/opcache/ZendAccelerator.c
index 99bb33573f3b..1ffd6cb3e5d4 100644
--- a/ext/opcache/ZendAccelerator.c
+++ b/ext/opcache/ZendAccelerator.c
@@ -3197,7 +3197,7 @@ static zend_result accel_post_startup(void)
 			size_t page_size;
 
 			page_size = zend_get_page_size();
-			if (!page_size && (page_size & (page_size - 1))) {
+			if (!page_size || (page_size & (page_size - 1))) {
 				zend_accel_error_noreturn(ACCEL_LOG_FATAL, "Failure to initialize shared memory structures - can't get page size.");
 				abort();
 			}