Language: array offset on non-container types must emit E_WARNING (zend_execute.c)

[PurHur]

Category

language · runtime

Problem

PHP 8+ warns when using [/] offset access on scalars that are not arrays/strings/ArrayAccess (Trying to access array offset on value of type bool). This compiler reads $x = true[0]; silently (no warning, $x null) and prints done.

Same class of bug as missing unary-+ warnings (#4723 / #4820) — invalid container access should warn under E_ALL, not fail silently.

php-src reference

• php/php-src Zend/zend_execute.c — ZEND_FETCH_DIM_R, zend_wrong_parameter_type_error / warnings for invalid offsets
• php/php-src Zend/zend_operators.c

Repro

./script/docker-exec.sh -- bash -lc 'source script/php-env.sh
php test/repro-maintainer/parity_array_offset_bool.php; echo zend:$?
php bin/vm.php test/repro-maintainer/parity_array_offset_bool.php; echo vm:$?
'

Engine	Output	exit
Zend	Warning: Trying to access array offset on value of type bool + done	0
VM	done only	0

Repro script: test/repro-maintainer/parity_array_offset_bool.php

Scope (this repo)

Area	Files
VM	lib/VM.php — dim fetch on bool/int/float/null/resource
JIT/AOT	mirror warning + null result after VM
Tests	test/compliance/cases/language/array_offset_invalid_type.phpt (bool + int smoke)

Done when

• Bool offset repro emits E_WARNING on VM under E_ALL
• Result value remains null like Zend (no fatal)
• ./script/ci-fast.sh --filter array_offset_invalid green

Links

• Language: unary + (+) on non-numeric strings — JIT/AOT E_WARNING + int(0) (phase 2 of #4723) #4820 (unary + warnings), Language: unary + (+) on non-numeric strings — E_WARNING and int(0) like Zend (zend_operators.c) #4723
• Epic: Self-host critical path — compiler compiles itself (M3→M5) #1492

[PurHur]

claim: cursor-worker-lane-c — starting this run

[PurHur]

Merged via #4884

Verification: ./script/docker-exec.sh -- bash -lc 'vendor/bin/phpunit --filter "array_offset_scalar_warning|dim_fetch_null_type_error" test/compliance/' → OK (6 tests, 6 assertions).

VM/JIT read on scalars now match Zend E_WARNING + null; object dim fetch uses catchable Error with php-src wording.