From 8c8fc99c1985081517267ac6b652638c03407985 Mon Sep 17 00:00:00 2001
From: PurHur <PurHur@users.noreply.github.com>
Date: Wed, 20 May 2026 20:57:34 +0000
Subject: [PATCH] Web: JIT isset() on $_GET/$_POST with dynamic string keys
 (#70)

Lower non-literal superglobal keys to __hashtable__offsetIsSetStringKey
at compile time so routers can use isset($_GET[$param]) under JIT.
Add VM compliance and real PHPT coverage; AOT isset on superglobals
still segfaults at link (pre-existing, tracked separately).

Co-authored-by: Cursor <cursoragent@cursor.com>
---
 lib/JIT/IssetHelper.php                       | 22 ++++++++++++++++++-
 .../cases/stdlib/isset_get_dynamic_key.phpt   | 19 ++++++++++++++++
 .../real/cases/web_isset_get_dynamic_key.phpt | 15 +++++++++++++
 3 files changed, 55 insertions(+), 1 deletion(-)
 create mode 100644 test/compliance/cases/stdlib/isset_get_dynamic_key.phpt
 create mode 100644 test/real/cases/web_isset_get_dynamic_key.phpt

diff --git a/lib/JIT/IssetHelper.php b/lib/JIT/IssetHelper.php
index 4925b7332f6..d65ca5e63be 100644
--- a/lib/JIT/IssetHelper.php
+++ b/lib/JIT/IssetHelper.php
@@ -165,8 +165,28 @@ private static function compileHashTableOffsetIsSet(
 
                 return $context->getTypeFromString('int1')->constInt($known ? 1 : 0, false);
             }
+            $ht = $context->helper->loadValue($container);
+            if (Variable::TYPE_STRING === $dim->type) {
+                return $context->builder->call(
+                    $context->lookupFunction('__hashtable__offsetIsSetStringKey'),
+                    $ht,
+                    $context->helper->loadValue($dim)
+                );
+            }
+            if (Variable::TYPE_NATIVE_LONG === $dim->type) {
+                $index = $context->builder->truncOrBitCast(
+                    $context->helper->loadValue($dim),
+                    $context->getTypeFromString('size_t')
+                );
+
+                return $context->builder->call(
+                    $context->lookupFunction('__hashtable__offsetIsSet'),
+                    $ht,
+                    $index
+                );
+            }
             throw new \LogicException(
-                'isset() on superglobals only supports a string literal key in this compiler build'
+                'isset() on superglobals only supports string or integer keys in this compiler build'
             );
         }
 
diff --git a/test/compliance/cases/stdlib/isset_get_dynamic_key.phpt b/test/compliance/cases/stdlib/isset_get_dynamic_key.phpt
new file mode 100644
index 00000000000..b518f0ecc34
--- /dev/null
+++ b/test/compliance/cases/stdlib/isset_get_dynamic_key.phpt
@@ -0,0 +1,19 @@
+--TEST--
+stdlib isset() on $_GET with non-literal string key (issue #70)
+--ENV--
+QUERY_STRING=name=Ada
+--FILE--
+<?php
+$key = 'name';
+if (isset($_GET[$key])) {
+    echo $_GET[$key], "\n";
+} else {
+    echo "missing\n";
+}
+$missing = 'absent';
+if (!isset($_GET[$missing])) {
+    echo "absent ok\n";
+}
+--EXPECT--
+Ada
+absent ok
diff --git a/test/real/cases/web_isset_get_dynamic_key.phpt b/test/real/cases/web_isset_get_dynamic_key.phpt
new file mode 100644
index 00000000000..5b0126abd00
--- /dev/null
+++ b/test/real/cases/web_isset_get_dynamic_key.phpt
@@ -0,0 +1,15 @@
+--TEST--
+Web: isset() on $_GET with non-literal string key (issue #70)
+--ENV--
+QUERY_STRING=name=World
+--FILE--
+<?php
+$key = 'name';
+if (isset($_GET[$key])) {
+    echo 'Hello ', $_GET[$key], "\n";
+} else {
+    echo "Hello Guest\n";
+}
+--EXPECT--
+Hello World
+