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.
I think it's reasonable to assume that the only possible types
are those that are declared, and null, because null is what
return_value is initialized to.
Make sure explicitly specified func_info is a subset of
automatically computed info. This will at least prevent
cases where a type is removed from stubs, but not removed
from func_info.
Closes GH-5471.
Mark "throw" used in expression context with a flag, and don't
treat it as a BB terminator in that case. This prevents us from
optimizing away the following opcodes as unreachable, which may
result in live ranges being dropped incorrectly.
Close GH-5450.
`func_get_args()` may return `zend_empty_array`, which has refcount 2
to enforce separation. We have to cater to that during type inference
so that the optimization in the JIT macro `SEPARATE_ARRAY` doesn't
prevent the separation.
Only leave OP_RANGE macros, which always have the "EX" behavior.
This was already done for most other macros before, but these
were missed. This helps avoid mistakes by using the wrong macro.
