moar docs, IDK if this is too much, but it covers everything

Author: realFlowControl

UPGRADING.INTERNALS

@@ -38,7 +38,42 @@ PHP 8.4 INTERNALS UPGRADE NOTES
   out zend_string*. This won't cut off the string if it embeds a NUL byte.
 
 * zend_mm_set_custom_debug_handlers() has been removed from ZendMM, use
-  zend_mm_set_custom_handlers() instead
+  zend_mm_set_custom_handlers() instead which now supports DEBUG builds
+
+* zend_mm_set_custom_handlers() has changed its signature from
+  void()(zend_mm_heap *heap,
+         void* (*_malloc)(size_t),
+         void  (*_free)(void*),
+         void* (*_realloc)(void*, size_t))
+  to
+  void()(zend_mm_heap *heap,
+         void* (*_malloc)(size_t ZEND_FILE_LINE_DC ZEND_FILE_LINE_ORIG_DC),
+         void  (*_free)(void* ZEND_FILE_LINE_DC ZEND_FILE_LINE_ORIG_DC),
+         void* (*_realloc)(void*, size_t ZEND_FILE_LINE_DC ZEND_FILE_LINE_ORIG_DC))
+
+* zend_mm_get_custom_handlers() has changed its signature from
+  void()(zend_mm_heap *heap,
+         void* (**_malloc)(size_t),
+         void  (**_free)(void*),
+         void* (**_realloc)(void*, size_t))
+  to
+  void()(zend_mm_heap *heap,
+         void* (**_malloc)(size_t ZEND_FILE_LINE_DC ZEND_FILE_LINE_ORIG_DC),
+         void  (**_free)(void* ZEND_FILE_LINE_DC ZEND_FILE_LINE_ORIG_DC),
+         void* (**_realloc)(void*, size_t ZEND_FILE_LINE_DC ZEND_FILE_LINE_ORIG_DC))
+
+* __zend_malloc() has changed their signature from
+  void(*)(size_t) to
+  void(*)(size_t ZEND_FILE_LINE_DC ZEND_FILE_LINE_ORIG_DC)
+
+* __zend_calloc() has changed their signature from
+  void(*)(size_t, size_t) to
+  void(*)(size_t, size_t ZEND_FILE_LINE_DC ZEND_FILE_LINE_ORIG_DC)
+
+* __zend_realloc() has changed their signature from
+  void(*)(void *, size_t) to
+  void(*)(void *, size_t ZEND_FILE_LINE_DC ZEND_FILE_LINE_ORIG_DC)
+
 
 ========================
 2. Build system changes