From 600402d986984ec36fc0b5a375f35eae4a266558 Mon Sep 17 00:00:00 2001
From: fishmore <37470985+bigboysun@users.noreply.github.com>
Date: Wed, 7 Apr 2021 16:30:55 +0800
Subject: [PATCH] Update zend_alloc.c

Don't free main thunk.  It will crash.
---
 Zend/zend_alloc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Zend/zend_alloc.c b/Zend/zend_alloc.c
index 5458e7acf6c..f5fbee676db 100644
--- a/Zend/zend_alloc.c
+++ b/Zend/zend_alloc.c
@@ -1099,7 +1099,7 @@ static zend_always_inline void zend_mm_free_pages_ex(zend_mm_heap *heap, zend_mm
 		/* this setting may be not accurate */
 		chunk->free_tail = page_num;
 	}
-	if (free_chunk && chunk->free_pages == ZEND_MM_PAGES - ZEND_MM_FIRST_PAGE) {
+	if (free_chunk && chunk != heap->main_chunk && chunk->free_pages == ZEND_MM_PAGES - ZEND_MM_FIRST_PAGE) {
 		zend_mm_delete_chunk(heap, chunk);
 	}
 }