Regression: extension_loaded('gmp') + gmp_* callable on default profile — Zend false (ext/gmp)

[PurHur]

Category

Stdlib · php-src-strict · extension advertisement (re-shape of #22791 / #22790; gmp surface already landed via #3341+)

Problem

Host Zend without ext/gmp reports extension_loaded('gmp') false and function_exists('gmp_add') false. The VM always advertises gmp and executes gmp_add successfully on the default/reference profile.

GMP APIs themselves are largely implemented (#3341 and follow-ups). This ticket is the introspection / default-profile gate so extension_loaded / function_exists match Zend when gmp is not part of the reference build.

Probed 2026-07-24 (host PHP 8.2.32, gmp absent).

Repro	Zend 8.2+ (no gmp)	VM (2026-07-24)
extension_loaded('gmp')	false	true
function_exists('gmp_add')	false	true
gmp_strval(gmp_add('2','3'))	undefined function	5

php-src reference

• php/php-src ext/gmp/gmp.c — module + gmp_* registration
• php/php-src ext/standard/basic_functions.c — extension_loaded / function_exists

PHP implementation target

• Gate ext/gmp Module registration / BuiltinIntrospectionPolicy (or equivalent extension policy) so default/reference profile matches Zend’s loaded set
• When gmp is enabled for a profile, keep existing PHP implementations in ext/gmp — do not reintroduce C builtins
• Mirror the sqlite3 / Pdo\Sqlite profile-gate fixes (Regression: extension_loaded('sqlite3') + SQLite3Exception without SQLite3 on default 8.2 profile (re-#17106, ext/sqlite3) #22791 / Regression: Pdo\Sqlite class_exists true on default 8.2 profile — Zend undefined (re-#22600, ext/pdo_sqlite/pdo_sqlite.stub.php) #22790)

Repro

./script/docker-exec.sh -- bash -lc 'php test/repro/extension_loaded_gmp_phantom.php'
./script/docker-exec.sh -- bash -lc 'php bin/vm.php test/repro/extension_loaded_gmp_phantom.php'

Done when

• Default/reference profile without gmp: extension_loaded('gmp') and function_exists('gmp_add') are false
• With gmp enabled for the profile/build: both true and gmp_add still works
• Compliance .phpt under test/compliance/cases/
• php-src-strict; no php-compiler-strict shortcut

[PurHur]

Self-contained repro (no tree file required)

./script/docker-exec.sh -- bash -lc "php -r 'echo extension_loaded(\"gmp\")?\"ext=yes\\n\":\"ext=no\\n\"; echo function_exists(\"gmp_add\")?\"gmp_add=yes\\n\":\"gmp_add=no\\n\";'"
./script/docker-exec.sh -- bash -lc "php bin/vm.php -r 'echo extension_loaded(\"gmp\")?\"ext=yes\\n\":\"ext=no\\n\"; echo function_exists(\"gmp_add\")?\"gmp_add=yes\\n\":\"gmp_add=no\\n\"; if(function_exists(\"gmp_add\")) echo gmp_strval(gmp_add(\"2\",\"3\")),\"\\n\";'"

[PurHur]

Trust probe (before claim)

Gate	Status	Note
bootstrap-inventory --check	ok	release-readiness: OK 6518/6518
release-readiness --json	partial	user_release_ready: no — north-star5-fast fail (gen-0 manifest/driver mismatch #8713 / #22642); other gates ok
bootstrap-selfhost-link	partial	stale gen-0 → Zend gen-0 fallback (#21855/#2842); compile still running

#22858 SNMP user-bucket already green on host VM (user=0 / SNMP undef / ext=no). Picking this gmp advertisement gate instead.

claim: PHP Compiler STD Lib — starting this run (#22860 extension_loaded/gmp_* phantom on reference profile)

[PurHur]

claim: PHP Compiler STD Lib Advanced — batch (issues #22841, #22859, #22860)

Starting with #22841 (positive VmStatCache / filesize·filemtime retention). Then sequential PRs for soap/gmp default-profile advertisement gates.

[PurHur]

Merged via https://github.com/PurHur/php-compiler/pull/'"$PR"'

Verification: VM default matches Zend (gmp + gmp_add + GMP all false); PHP_COMPILER_PROFILE=8.4 re-enables; phantom PHPT + GmpExtensionPolicyTest green; inventory OK 6519/6519.

Enable: host php-gmp or PHP_COMPILER_PROFILE=8.4.