diff --git a/Zend/tests/gh10709.phpt b/Zend/tests/gh10709.phpt
new file mode 100644
index 00000000000..f394e1a7882
--- /dev/null
+++ b/Zend/tests/gh10709.phpt
@@ -0,0 +1,21 @@
+--TEST--
+GH-10709: Recursive class constant evaluation
+--FILE--
+<?php
+
+class B { const C = A::C . "B"; }
+
+spl_autoload_register(function ($class) {
+    class A { const C = "A"; }
+    var_dump(B::C);
+});
+
+try {
+    new B();
+} catch (Error $e) {
+    echo $e->getMessage(), "\n";
+}
+
+?>
+--EXPECT--
+string(2) "AB"
diff --git a/Zend/tests/gh10709_2.phpt b/Zend/tests/gh10709_2.phpt
new file mode 100644
index 00000000000..723fa29cc94
--- /dev/null
+++ b/Zend/tests/gh10709_2.phpt
@@ -0,0 +1,30 @@
+--TEST--
+GH-10709: Recursive class constant evaluation
+--FILE--
+<?php
+
+class B {
+    public $prop = A::C;
+}
+
+spl_autoload_register(function ($class) {
+    class A { const C = "A"; }
+    var_dump(new B());
+});
+
+try {
+    var_dump(new B());
+} catch (Error $e) {
+    echo $e->getMessage(), "\n";
+}
+
+?>
+--EXPECT--
+object(B)#2 (1) {
+  ["prop"]=>
+  string(1) "A"
+}
+object(B)#2 (1) {
+  ["prop"]=>
+  string(1) "A"
+}
diff --git a/Zend/tests/gh10709_3.phpt b/Zend/tests/gh10709_3.phpt
new file mode 100644
index 00000000000..1b0ccb5f8f2
--- /dev/null
+++ b/Zend/tests/gh10709_3.phpt
@@ -0,0 +1,43 @@
+--TEST--
+GH-10709: Recursive class constant evaluation with outer call failing
+--FILE--
+<?php
+
+class S {
+    public function __toString() {
+        static $i = 0;
+        $i++;
+        if ($i === 1) {
+            return 'S';
+        } else {
+            throw new \Exception('Thrown from S');
+        }
+    }
+}
+
+const S = new S();
+
+class B {
+    public $prop = A::C . S;
+}
+
+spl_autoload_register(function ($class) {
+    class A { const C = "A"; }
+    var_dump(new B());
+});
+
+var_dump(new B());
+
+?>
+--EXPECTF--
+object(B)#3 (1) {
+  ["prop"]=>
+  string(2) "AS"
+}
+
+Fatal error: Uncaught Exception: Thrown from S in %s:%d
+Stack trace:
+#0 %s(%d): [constant expression]()
+#1 %s(%d): S->__toString()
+#2 {main}
+  thrown in %s on line %d
diff --git a/Zend/zend_execute_API.c b/Zend/zend_execute_API.c
index cf1be1b5ad1..9b10db265da 100644
--- a/Zend/zend_execute_API.c
+++ b/Zend/zend_execute_API.c
@@ -698,7 +698,19 @@ ZEND_API zend_result ZEND_FASTCALL zval_update_constant_with_ctx(zval *p, zend_c
 			zval tmp;
 			bool short_circuited;
 
-			if (UNEXPECTED(zend_ast_evaluate_ex(&tmp, ast, scope, &short_circuited, ctx) != SUCCESS)) {
+			// Increase the refcount during zend_ast_evaluate to avoid releasing the ast too early
+			// on nested calls to zval_update_constant_ex which can happen when retriggering ast
+			// evaluation during autoloading.
+			zend_ast_ref *ast_ref = Z_AST_P(p);
+			bool ast_is_refcounted = !(GC_FLAGS(ast_ref) & GC_IMMUTABLE);
+			if (ast_is_refcounted) {
+				GC_ADDREF(ast_ref);
+			}
+			zend_result result = zend_ast_evaluate_ex(&tmp, ast, scope, &short_circuited, ctx) != SUCCESS;
+			if (ast_is_refcounted && !GC_DELREF(ast_ref)) {
+				rc_dtor_func((zend_refcounted *)ast_ref);
+			}
+			if (UNEXPECTED(result != SUCCESS)) {
 				return FAILURE;
 			}
 			zval_ptr_dtor_nogc(p);
diff --git a/ext/opcache/zend_persist.c b/ext/opcache/zend_persist.c
index 9698d584e80..cca90bb41e9 100644
--- a/ext/opcache/zend_persist.c
+++ b/ext/opcache/zend_persist.c
@@ -261,6 +261,7 @@ static void zend_persist_zval(zval *z)
 				zend_persist_ast(GC_AST(old_ref));
 				Z_TYPE_FLAGS_P(z) = 0;
 				GC_SET_REFCOUNT(Z_COUNTED_P(z), 1);
+				GC_ADD_FLAGS(Z_COUNTED_P(z), GC_IMMUTABLE);
 				efree(old_ref);
 			}
 			break;
diff --git a/run-tests.php b/run-tests.php
index 1f21b5073f3..5101f7845d9 100755
--- a/run-tests.php
+++ b/run-tests.php
@@ -675,6 +675,7 @@ function main(): void
     if (!$phpdbg) {
         $phpdbg = get_binary($php, 'phpdbg', 'sapi/phpdbg/phpdbg');
     }
+    $phpdbg = null;
 
     putenv("TEST_PHP_EXECUTABLE=$php");
     $environment['TEST_PHP_EXECUTABLE'] = $php;