Regression: include/require(+_once) expression returns NULL — Zend returns 1 or file return (re-#4483, Zend/zend_execute.c)

[PurHur]

Category

language · php-src-strict · include/require return semantics

Problem

#4483 claimed include/require return parity, but expression forms still return NULL on VM when Zend returns int(1) (successful include with no return) or the file's return value.

Verified 2026-07-21 (Docker php 8.2.32 vs bin/vm.php):

Repro	Zend 8.2	VM
var_export(require_once $emptyPhpFile) (<?php only)	1	NULL
var_export(include_once $emptyPhpFile)	1	NULL
var_export(include $emptyPhpFile)	1	NULL
var_export(require $fileReturning7) (<?php return 7;)	7	NULL

This breaks common $config = require 'config.php'; patterns and self-host/bootstrap scripts that use include-as-expression.

php-src reference

• php/php-src Zend/zend_execute.c — ZEND_INCLUDE_OR_EVAL return value (1 on success when included file does not return)
• php/php-src Zend/zend_execute_API.c — compile/execute inclusion entrypoints

PHP implementation target

• VM include/require opcode path (lib/VM.php / include helpers) — propagate included-frame return; default success to 1 not null
• JIT/AOT include lowering — same return semantics; prefer PHP helpers over new C
• Re-Language/runtime: include/require (+ *_once) — file resolution, scope, and return semantics parity #4483; keep once-path / path-resolution behavior intact

Repro

./script/docker-exec.sh -- bash -lc 'cat > /tmp/req_ret.php <<'"'"'PHP'"'"'
<?php
file_put_contents("/tmp/empty_req.php", "<?php\n");
file_put_contents("/tmp/ret7.php", "<?php return 7;\n");
echo "empty="; var_export(require_once "/tmp/empty_req.php"); echo "\n";
echo "ret7="; var_export(require "/tmp/ret7.php"); echo "\n";
PHP
php /tmp/req_ret.php; php bin/vm.php /tmp/req_ret.php'

Done when

• Successful include/require/include_once/require_once with no file return yield 1 (truthy int) as expression values on VM
• File return $x is the expression value of require/include (once variants on first load)
• Compliance .phpt covering empty success + explicit return
• php-src-strict; no php-compiler-strict shortcut

[PurHur]

claim: lane-C implementer — starting this run

[PurHur]

Merged in #21945.

Verification

• Issue repro: php bin/vm.php matches Zend (empty=1, ret7=7) for var_export(require_once/require …).
• IncludeRequireVMTest green; compliance include_require_expr_return green on VM + JIT.
• Fix: Include_ as inline call-arg producer + ErrorSuppress end-block guard so @mkdir does not steal later include expression results.