Add ZVAL_CHAR/RETVAL_CHAR/RETURN_CHAR as a shortcut for using
ZVAL_INTERNED_STRING and ZSTR_CHAR.
Add zend_string_init_fast() as a helper for the empty string /
one char interned string / zend_string_init() pattern.
Also add corresponding ZVAL_STRINGL_FAST etc macros.
Closes GH-5684.
If the array is empty, then I'd expect that the generator is never left,
and that can be converted to a no-op and the return value would always be `null`.
Make `yield from [];` as efficient as `if (false) { yield null; }`
when opcache's sccp pass is enabled.
Closes GH-5679
Currently, disabling a function only replaces the internal
function handler with one that throws a warning, and a few
places in the engine special-case such functions, such as
function_exists. This leaves us with a Schrödinger's function,
which both does not exist (function_exists returns false) and
does exist (you cannot define a function with the same name).
In particular, this prevents the implementation of robust
polyfills, as reported in https://bugs.php.net/bug.php?id=79382:
if (!function_exists('getallheaders')) {
function getallheaders(...) { ... }
}
If getallheaders() is a disabled function, this code will break.
This patch changes disable_functions to remove the functions from
the function table completely. For all intents and purposes, it
will look like the function does not exist.
This also renders two bits of PHP functionality obsolete and thus
deprecated:
* ReflectionFunction::isDisabled(), as it will no longer be
possible to construct the ReflectionFunction of a disabled
function in the first place.
* get_defined_functions() with $exclude_disabled=false, as
get_defined_functions() now never returns disabled functions.
Fixed bug #79382.
Closes GH-5473.
As far as I can determine, this is no longer a problem: We will
not try to remove the defining instructions (this is only done if
the value is known by SCCP itself) and we also only determine
non-refcounted values in this way, so it is not a problem if the
FREE is omitted.
We need to check result_use rather than result_def for a null zval.
Previously we were later assuming that the null zval is really a
partial array, which does not go well.