diff options
Diffstat (limited to 'UPGRADING.INTERNALS')
| -rw-r--r-- | UPGRADING.INTERNALS | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/UPGRADING.INTERNALS b/UPGRADING.INTERNALS index 132a2d97a7..8f4046032b 100644 --- a/UPGRADING.INTERNALS +++ b/UPGRADING.INTERNALS @@ -8,6 +8,7 @@ PHP 7.4 INTERNALS UPGRADE NOTES e. php_win32_error_to_msg() memory management f. get_properties_for() handler / Z_OBJDEBUG_P g. Required object handlers + h. Immutable classes and op_arrays 2. Build system changes a. Abstract @@ -121,6 +122,20 @@ PHP 7.4 INTERNALS UPGRADE NOTES It is recommended to initialize object handler structures by copying the std object handlers and only overwriting those you want to change. + h. Opcache may make classes and op_arrays immutable. Such classes are marked + by ZEND_ACC_IMMUTABLE flag, they are not going to be copied from opcache + shared memory to process memory and must not be modified at all. + Few related data structures were changed to allow addressing mutable data + structures from immutable ones. This access is implemented through + ZEND_MAP_PTR... abstraction macros and, basically, uses additional level of + indirection. op_array->run_time_cache, op_array->static_variables_ptr and + class_entry->static_members_table now have to be accessed through + ZEND_MAP_PTR... macros. + It's also not allowed to change op_array->reserved[] handles of immutable + op_arrays. Instead, now you have to reserve op_array handle using + zend_get_op_array_extension_handle() during MINIT and access its value + using ZEND_OP_ARRAY_EXTENSION(op_array, handle). + ======================== 2. Build system changes ======================== |