Fix @ suppress slot stealing hoisted null call args (#13248)

[PurHur]

Summary

• Root cause: #15916 post-ErrorSuppressBlock slot inheritance treated the first dead inline call-arg temp on any following call as the silenced inner result. After @mkdir($dir), hoisted null/[] operands for stream_context_create() were wired to mkdir's bool return slot.
• Fix: Only forward the suppress FUNCCALL_EXEC_RETURN slot when the outer call actually consumes the suppressed inner expression (callInErrorSuppressEndBlockUsesInnerResultAsArg). Preserves var_export(@get_cfg_var(...), true) (Regression: get_cfg_var('display_errors') — returns true not empty string (ext/standard/ini.c) #15916) and inline @stat forwarding (Stdlib: stat()/lstat() on missing path — returns NULL not false (ext/standard/stat.c) #10336).

php-src reference

• ext/standard/streams.c — stream_context_create() accepts null/empty array
• ext/standard/file.c — copy() optional $context third argument

Verification

./script/docker-exec.sh -- bash -lc 'source script/php-env.sh
php bin/vm.php test/repro/maintainer_gap_copy_stream_context.php
php bin/vm.php test/compliance/cases/stdlib/copy_stream_context.phpt
php bin/compile.php -l test/repro/maintainer_gap_copy_stream_context.php
vendor/bin/phpunit --filter "copy_stream_context|get_cfg_var_display_errors|ErrorSuppressInlineReturnSlotTest"
'

Output (2026-07-04):

copy_stream_context_ok=1
bool(true)
.... OK (10 tests, 20 assertions)

Relates to closed #13248 (copy $context arg) and #15916 (@ suppress forwarding).

Made with Cursor