Language: Exception::__construct($previous) throws LogicException — Zend TypeError (Zend/zend_exceptions.c)

[PurHur]

Category

language · php-src-strict · Exception $previous typing

Problem

Passing a non-Throwable object as Exception/Error $previous must raise TypeError with Zend’s argument message. php-compiler throws host LogicException (Exception previous must implement Throwable / must be an object) from ExceptionSupport::setExceptionPrevious.

Probed 2026-08-07 vs host Zend 8.2.32 (VM).

Repro	Zend	VM
throw new Exception("m", 0, new stdClass);	TypeError: Exception::__construct(): Argument #3 ($previous) must be of type ?Throwable, stdClass given	LogicException: Exception previous must implement Throwable
valid ?Throwable previous	chains via getPrevious()	OK

php-src reference

• php/php-src Zend/zend_exceptions.c — zend_parse_parameters(..., "|SlO!", ..., &previous, zend_ce_throwable) (O! → TypeError on wrong class)
• php/php-src Zend/zend_exceptions.stub.php — ?Throwable $previous = null

PHP implementation target

• lib/VM/ExceptionSupport.php — setExceptionPrevious: emit userland TypeError with Zend wire message (reuse shared arg TypeError helpers), not host LogicException
• Same path for ErrorException sixth arg / Error construct

Repro

./script/docker-exec.sh -- bash -lc 'cat > /tmp/ex_prev.php <<'"'"'PHP'"'"'
<?php
try {
  throw new Exception("m", 0, new stdClass);
} catch (Throwable $e) {
  echo get_class($e), "|", $e->getMessage(), "\n";
}
PHP
php /tmp/ex_prev.php
php bin/vm.php /tmp/ex_prev.php'

Done when

• Non-Throwable $previous → TypeError with Zend message text (VM + JIT)
• Valid Throwable previous still chains
• Compliance .phpt under test/compliance/cases/language/
• php-src-strict; no php-compiler-strict shortcut

[PurHur]

claim: compile-link trust automation — starting this run (Pillar 1 helper-runtime prelink now green via #28799; claiming this language TypeError parity fix)

[PurHur]

Merged via #28802

Verification: Zend/VM/JIT all emit TypeError|Exception::__construct(): Argument #3 ($previous) must be of type ?Throwable, stdClass given on the issue repro; Error/ErrorException arg positions match; valid Throwable still chains. Compliance phpt added (language/exception_ctor_previous_typeerror.phpt); FILE output matched EXPECT under php / bin/vm.php / bin/jit.php.