php-in-php: json_decode() JIT/AOT — delete phpc_json_decode.c (~649 lines), native VmJson (pairs #4795) #5302

Category

php-in-php | bootstrap | stdlib

Problem

#4795 tracks bootstrap-native JSON without host ext/json. Today lib/AOT/runtime/phpc_json_decode.c (~649 lines) implements a parallel JSON parser in C for JIT/AOT while VM may delegate to host json_decode(). Self-host (M5) requires JSON in compiled PHP (ext/standard/VmJson.php or equivalent), not a growing C decoder.

php-src reference

• php/php-src ext/json/php_json.c — PHP_FUNCTION(json_decode), php_json_decode_ex
• php/php-src ext/json/json_parser.tab.c — parser (reference only; implement in PHP)

Repro (failure today)

./script/docker-exec.sh -- bash -lc 'source script/php-env.sh
php bin/vm.php -r "var_dump(json_decode(\"{\\\"a\\\":1}\", true));"
test -f lib/AOT/runtime/phpc_json_decode.c && wc -l lib/AOT/runtime/phpc_json_decode.c
'

Target: one PHP implementation compiled through the pipeline; delete C.

Scope (this repo)

Done when

• json_decode('{"a":1}', true) matches Zend on VM, JIT, and AOT without host json_*
• phpc_json_decode.c removed; PR notes ~649 lines removed from runtime/
• ./script/ci-fast.sh --filter json_decode green
• Bootstrap inventory check passes JSON symbols natively (Bootstrap: VmJson json_encode/json_decode — native serialization without host json extension #4795 criteria)

Related

• Bootstrap: VmJson json_encode/json_decode — native serialization without host json extension #4795 bootstrap VmJson · Stdlib: json_decode() depth, flags, and JSON_THROW_ON_ERROR / JsonException (ext/json parity) #3267 flags/depth · Stdlib: json_encode() flags and JSON_* constants (ext/json parity, phase 2 of #3267) #3281 json_encode flags

Links

• North star: Epic: Self-host critical path — compiler compiles itself (M3→M5) #1492