The error is now detected earlier, so the message ends up being
different.

Squashed commit of the following:

commit 8b45fa2acb8cd92542a39e1e4720fe1f4fabc26c
Author: Dmitry Stogov <dmitry@zend.com>
Date:   Thu Jun 16 01:52:50 2016 +0300

    Separate slow path of ZEND_RECV into a cold function.

commit 9e18895ee59c64c93a96b1ba3061355c4663e962
Author: Dmitry Stogov <dmitry@zend.com>
Date:   Wed Jun 15 23:26:28 2016 +0300

    Required argument can't be IS_UNDEF anymore.

commit 662db66e3943d4455c65e4f987bb54abf724ecb2
Author: Dmitry Stogov <dmitry@zend.com>
Date:   Tue May 31 17:14:50 2016 +0300

    Replace "Missing argument" warning by "Too few arguments" exception.

Squashed commit of the following:

commit bdd3b6895c3ce3eacfcf7d4bf4feb8dfa61801fd
Author: Dmitry Stogov <dmitry@zend.com>
Date:   Thu Jun 16 00:19:42 2016 +0300

    Fixed GOTO VM

commit 2f1d7c8b89ce821086d357cf65f629f040a85c03
Author: Dmitry Stogov <dmitry@zend.com>
Date:   Wed Jun 15 21:01:57 2016 +0300

    Removed unused variable

commit cf749c42b0b1919f70b1e7d6dcbfff76899506af
Author: Dmitry Stogov <dmitry@zend.com>
Date:   Wed Jun 15 19:06:16 2016 +0300

    Protection from $this reassign through mb_parse_str()

commit 59a9a6c83c66b666971e57f1173b33a422166efd
Author: Dmitry Stogov <dmitry@zend.com>
Date:   Wed Jun 15 18:14:50 2016 +0300

    Added type inference rule for FETCH_THIS opcode

commit 73f8d14a856f14a461430b3c7534ab2ce870cbf6
Author: Dmitry Stogov <dmitry@zend.com>
Date:   Wed Jun 15 18:11:18 2016 +0300

    Restored PHP-7 behavior of isset($this->foo).
    It throws exception if not in object context.
    Removed useless opcode handlers.

commit fa0881381e8ae97e022ae5d1ec0851c952f33c82
Author: Dmitry Stogov <dmitry@zend.com>
Date:   Tue May 31 12:25:47 2016 +0300

    Changed "Notice: Undefined variable: this" into "Exception: Using $this when not in object context".

commit e32cc528c0f2c97963d8ec83eff0269f1f45af18
Author: Dmitry Stogov <dmitry@zend.com>
Date:   Tue May 24 02:02:43 2016 +0300

    Throw exception on attempt to re-assign $this through extract() and parse_str().

commit 41f1531b52113ec8a4c208aa6b9ef50f1386bb3f
Author: Dmitry Stogov <dmitry@zend.com>
Date:   Mon May 23 22:18:36 2016 +0300

    Fixed inconsistent $this behavior

Squashed commit of the following:

commit f11ca0e7a57793fa0e3e7f6d451720e6c42bb0b9
Author: Dmitry Stogov <dmitry@zend.com>
Date:   Tue Dec 8 12:38:42 2015 +0300

    Fixed test expectation

commit 211f873f542504d0a0f72b6b5cb23908a1c99a2d
Author: Dmitry Stogov <dmitry@zend.com>
Date:   Tue Dec 8 12:28:38 2015 +0300

    Embed zend_class_constant.flags into zend_class_constants.value.u2.access_flags

commit 51deab84b2cdbf9cdb1a838cf33b2ee45c61748b
Author: Dmitry Stogov <dmitry@zend.com>
Date:   Mon Dec 7 11:18:55 2015 +0300

    Fixed issues found by Nikita

commit 544dbd5b47e40d38a8ccb96bc5583e9cb7fdd723
Author: Dmitry Stogov <dmitry@zend.com>
Date:   Sat Dec 5 02:41:05 2015 +0300

    Refactored immplementation of https://wiki.php.net/rfc/class_const_visibility
    @reeze created an RFC here and I emailed internals here and didn't get any responses positive/negative.