It is very hard to determine in advance whether class linking will
fail due to missing dependencies in variance checks (#7314 attempts
this). This patch takes an alternative approach where we try to
perform inheritance on a copy of the class (zend_lazy_class_load)
and then restore the original class if inheritance fails. The fatal
error in that case is recorded and thrown as a warning later.
Closes GH-7319.
Instead always use the unlinked_uses table, which is already used
if opcache is used. Not much point in having a different mechanism
for the non-opcache case.
Currently, classes that can't be linked get moved back into the original script
and are not preloaded. As such classes may be referenced from functions that
did get preloaded, there is a preload autoload mechanism to load them at
runtime.
Since PHP 8.1, we can safely preload unlinked classes, which will then go
through usual lazy loading. This means that we no longer need the preload
autoload mechanism. However, we need to be careful not to modify any hash
table buckets in-place, and should create new buckets for lazy loaded classes.
When running without opcache, static_members_table is shared with
default_static_members_table. This is visible in reflection output,
because ReflectionProperty::getDefaultValue() will return the
current value, rather than the default value.
Address this by never sharing the table, which matches the behavior
we already see under opcache.
Fixes bug #80821.
Closes GH-7299.
Convert zend_hash_find_ex(..., 1) to zend_hash_find_known_hash(...)
Convert zend_hash_find_ex(..., 0) to zend_hash_find(...)
Also add serializable changes to UPGRADING.INTERNALS summary
Add support for readonly properties, for which only a single
initializing assignment from the declaring scope is allowed.
RFC: https://wiki.php.net/rfc/readonly_properties_v2
Closes GH-7089.
This prevents serialization and unserialization of a class and its
children in a way that does not depend on the zend_class_serialize_deny
and zend_class_unserialize_deny handlers that will be going away
in PHP 9 together with the Serializable interface.
In stubs, `@not-serializable` can be used to set this flag.
This patch only uses the new flag for a handful of Zend classes,
converting the remainder is left for later.
Closes GH-7249.
Fixes bug #81111.
Subtyping relationships established on internal classes are always
going to hold (if we ignore Windows), so there is no need to
explicitly track them.
This fixes an assertion failure in GH-7251.
If we have an UNRESOLVED result, simply register all classes that
occur in either of the types. I believe that's equivalent to what
we're currently doing in a more complicated way.
Now that inheritance can throw deprecations again, these may be
converted to exception by a custom error handler. In this case
we need to convert the exception to a fatal error, as inheritance
cannot safely throw in the general case.
mixed should be behaving the same way as no type here, and not
require X to be autoloaded. Everything apart from "void" is trivially
covariant to "mixed".
Userland property infos are no longer duplicated since PHP 7.4, when we
stopped setting SHADOW flags on inherited private properties. Stop duplicating
internal property infos as well.
This requires switching class destruction to work in reverse order, as child
classes may be reusing structures from parent classes, and as such should be
destroyed first.
Since 3e6b447979 it is again possible to have
warnings (deprecations) during inheritance, and more such functionality is
likely in the future. This is a problem, because such warnings will only be
shown on the first request if the opcache inheritance cache is used. This
currently causes test failures in --repeat builds.
Fix this by uplifting the error recording functionality from opcache to Zend,
and then using it to persist a warning trace in the inheritance cache, which
can then be used to replay the warnings on subsequent executions.
The never type can be used to indicate that a function never
returns, for example because it always unwinds.
RFC: https://wiki.php.net/rfc/noreturn_type
Closes GH-6761.
This PR corrects misspellings identified by the check-spelling action.
The misspellings have been reported at jsoref@b6ba3e2#commitcomment-48946465
The action reports that the changes in this PR would make it happy: jsoref@602417c
Closes GH-6822.
This is generalization of idea, that was previously usesd for caching
resolution of class_entries in zend_type. Now very similar mechanizm is
used for general zend_string into zend_class_entry resolution.
Interned zend_string with IS_STR_CLASS_NAME_MAP_PTR GC_FLAG uses its
refcount to adress corresponding zend_class_entry cache slot.
The refcount keeps an offset to this slot from CG(map_ptr_base).
Flag may be checked by ZSTR_HAS_CE_CACHE(str), cache slot may be read by
ZSTR_GET_CE_CACHE(str) and set by ZSTR_SET_CE_CACHE(str, ce).
When a method is inherited, the static variables will now always
use the initial values, rather than the values at the time of
inheritance. As such, behavior no longer depends on whether
inheritance happens before or after a method has been called.
This is implemented by always keeping static_variables as the
original values, and static_variables_ptr as the modified copy.
Closes GH-6705.
This is a new transparent technology that eliminates overhead of PHP class inheritance.
PHP classes are compiled and cached (by opcahce) separately, however their "linking" was done at run-time - on each request. The process of "linking" may involve a number of compatibility checks and borrowing methods/properties/constants form parent and traits. This takes significant time, but the result is the same on each request.
Inheritance Cache performs "linking" for unique set of all the depending classes (parent, interfaces, traits, property types, method types involved into compatibility checks) once and stores result in opcache shared memory. As a part of the this patch, I removed limitations for immutable classes (unresolved constants, typed properties and covariant type checks). So now all classes stored in opcache are "immutable". They may be lazily loaded into process memory, if necessary, but this usually occurs just once (on first linking).
The patch shows 8% improvement on Symphony "Hello World" app.
We're starting to see a mix between uses of zend_bool and bool.
Replace all usages with the standard bool type everywhere.
Of course, zend_bool is retained as an alias.
