Fix #81585: cached_chunks are not counted to real_size on shutdown

The amount of allocated system memory is kept in `real_size`, including
the allocated `cached_chunks`.  Thus, we need to keep the proper count
at the end of the shutdown.

Closes GH-7745.

NEWS

@@ -4,6 +4,8 @@ PHP                                                                        NEWS
 
 - Core:
   . Fixed bug #81656 (GCC-11 silently ignores -R). (Michael Wallner)
+  . Fixed bug #81585 (cached_chunks are not counted to real_size on shutdown).
+    (cmb)
 
 - Spl:
   . Fixed bug #75917 (SplFileObject::seek broken with CSV flags). (Aliaksandr

Zend/zend_alloc.c

@@ -2303,10 +2303,10 @@ void zend_mm_shutdown(zend_mm_heap *heap, bool full, bool silent)
 #endif
 		memset(heap->free_slot, 0, sizeof(heap->free_slot));
 #if ZEND_MM_STAT || ZEND_MM_LIMIT
-		heap->real_size = ZEND_MM_CHUNK_SIZE;
+		heap->real_size = (heap->cached_chunks_count + 1) * ZEND_MM_CHUNK_SIZE;
 #endif
 #if ZEND_MM_STAT
-		heap->real_peak = ZEND_MM_CHUNK_SIZE;
+		heap->real_peak = (heap->cached_chunks_count + 1) * ZEND_MM_CHUNK_SIZE;
 #endif
 		heap->chunks_count = 1;
 		heap->peak_chunks_count = 1;