diff --git a/NEWS b/NEWS
index 384565082cf92..c9a77af4b63a9 100644
--- a/NEWS
+++ b/NEWS
@@ -14,8 +14,8 @@ PHP                                                                        NEWS
   . Fixed bug GH-16665 (\array and \callable should not be usable in
     class_alias). (nielsdos)
   . Added PHP_BUILD_DATE constant. (cmb)
-  . Added support for Closures in constant expressions. (timwolla,
-    Volker Dusch)
+  . Added support for Closures and first class callables in constant
+    expressions. (timwolla, Volker Dusch)
   . Use `clock_gettime_nsec_np()` for high resolution timer on macOS
     if available. (timwolla)
   . Implement GH-15680 (Enhance zend_dump_op_array to properly represent
diff --git a/UPGRADING b/UPGRADING
index 7cfe2372ab98d..708303b32594c 100644
--- a/UPGRADING
+++ b/UPGRADING
@@ -85,8 +85,10 @@ PHP 8.5 UPGRADE NOTES
 
 - Core:
   . Closure is now a proper subtype of callable
-  . Added support for Closures in constant expressions.
+  . Added support for Closures and first class callables in constant
+    expressions.
     RFC: https://wiki.php.net/rfc/closures_in_const_expr
+    RFC: https://wiki.php.net/rfc/fcc_in_const_expr
   . Fatal Errors (such as an exceeded maximum execution time) now include a
     backtrace.
     RFC: https://wiki.php.net/rfc/error_backtraces_v2
diff --git a/Zend/tests/first_class_callable/constexpr/attributes.phpt b/Zend/tests/first_class_callable/constexpr/attributes.phpt
new file mode 100644
index 0000000000000..b011a7f678137
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/attributes.phpt
@@ -0,0 +1,50 @@
+--TEST--
+Allow defining FCC in attributes
+--EXTENSIONS--
+reflection
+--FILE--
+<?php
+
+#[Attribute(Attribute::TARGET_CLASS | Attribute::IS_REPEATABLE)]
+class Attr {
+    public function __construct(public Closure $value) {
+        var_dump($value('abc'));
+    }
+}
+
+#[Attr(strrev(...))]
+#[Attr(strlen(...))]
+class C {}
+
+foreach ((new ReflectionClass(C::class))->getAttributes() as $reflectionAttribute) {
+    var_dump($reflectionAttribute->newInstance());
+}
+
+?>
+--EXPECTF--
+string(3) "cba"
+object(Attr)#%d (1) {
+  ["value"]=>
+  object(Closure)#%d (2) {
+    ["function"]=>
+    string(6) "strrev"
+    ["parameter"]=>
+    array(1) {
+      ["$string"]=>
+      string(10) "<required>"
+    }
+  }
+}
+int(3)
+object(Attr)#%d (1) {
+  ["value"]=>
+  object(Closure)#%d (2) {
+    ["function"]=>
+    string(6) "strlen"
+    ["parameter"]=>
+    array(1) {
+      ["$string"]=>
+      string(10) "<required>"
+    }
+  }
+}
diff --git a/Zend/tests/first_class_callable/constexpr/attributes_ast_printing.phpt b/Zend/tests/first_class_callable/constexpr/attributes_ast_printing.phpt
new file mode 100644
index 0000000000000..2916c3dfff86d
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/attributes_ast_printing.phpt
@@ -0,0 +1,33 @@
+--TEST--
+AST printing for FCC in attributes
+--FILE--
+<?php
+
+// Do not use `false &&` to fully evaluate the function / class definition.
+
+try {
+    \assert(
+        !
+        #[Attr(strrev(...))]
+        function () { }
+    );
+} catch (Error $e) {
+    echo $e->getMessage(), "\n";
+}
+
+try {
+    \assert(
+        !
+        new #[Attr(strrev(...))]
+        class {}
+    );
+} catch (Error $e) {
+    echo $e->getMessage(), "\n";
+}
+
+?>
+--EXPECT--
+assert(!#[Attr(strrev(...))] function () {
+})
+assert(!new #[Attr(strrev(...))] class {
+})
diff --git a/Zend/tests/first_class_callable/constexpr/attributes_ast_printing_runtime.phpt b/Zend/tests/first_class_callable/constexpr/attributes_ast_printing_runtime.phpt
new file mode 100644
index 0000000000000..8ee0acbb6f0e4
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/attributes_ast_printing_runtime.phpt
@@ -0,0 +1,27 @@
+--TEST--
+AST printing for FCC in attributes at runtime
+--FILE--
+<?php
+
+namespace Test;
+
+class Clazz {
+	#[Attr(strrev(...), \strrev(...), Clazz::foo(...), self::foo(...))]
+	function foo() { }
+}
+
+$r = new \ReflectionMethod(Clazz::class, 'foo');
+foreach ($r->getAttributes() as $attribute) {
+    echo $attribute;
+}
+
+?>
+--EXPECT--
+Attribute [ Test\Attr ] {
+  - Arguments [4] {
+    Argument #0 [ Test\strrev(...) ]
+    Argument #1 [ \strrev(...) ]
+    Argument #2 [ \Test\Clazz::foo(...) ]
+    Argument #3 [ self::foo(...) ]
+  }
+}
diff --git a/Zend/tests/first_class_callable/constexpr/attributes_scope_001.phpt b/Zend/tests/first_class_callable/constexpr/attributes_scope_001.phpt
new file mode 100644
index 0000000000000..6e75004624191
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/attributes_scope_001.phpt
@@ -0,0 +1,28 @@
+--TEST--
+FCC in attribute may access private methods
+--EXTENSIONS--
+reflection
+--FILE--
+<?php
+
+#[Attribute(Attribute::TARGET_CLASS | Attribute::IS_REPEATABLE)]
+class Attr {
+    public function __construct(public Closure $value) {}
+}
+
+#[Attr(C::myMethod(...))]
+class C {
+    private static function myMethod(string $foo) {
+        echo "Called ", __METHOD__, PHP_EOL;
+        var_dump($foo);
+    }
+}
+
+foreach ((new ReflectionClass(C::class))->getAttributes() as $reflectionAttribute) {
+    ($reflectionAttribute->newInstance()->value)('abc');
+}
+
+?>
+--EXPECT--
+Called C::myMethod
+string(3) "abc"
diff --git a/Zend/tests/first_class_callable/constexpr/attributes_scope_002.phpt b/Zend/tests/first_class_callable/constexpr/attributes_scope_002.phpt
new file mode 100644
index 0000000000000..f93240c5fac8e
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/attributes_scope_002.phpt
@@ -0,0 +1,34 @@
+--TEST--
+FCC in attribute may not access unrelated private methods
+--EXTENSIONS--
+reflection
+--FILE--
+<?php
+
+#[Attribute(Attribute::TARGET_CLASS | Attribute::IS_REPEATABLE)]
+class Attr {
+    public function __construct(public Closure $value) {}
+}
+
+class E {
+    private static function myMethod(string $foo) {
+        echo "Called ", __METHOD__, PHP_EOL;
+        var_dump($foo);
+    }
+}
+
+#[Attr(E::myMethod(...))]
+class C {
+}
+
+foreach ((new ReflectionClass(C::class))->getAttributes() as $reflectionAttribute) {
+    ($reflectionAttribute->newInstance()->value)('abc');
+}
+
+?>
+--EXPECTF--
+Fatal error: Uncaught Error: Call to private method E::myMethod() from scope C in %s:%d
+Stack trace:
+#0 %s(%d): ReflectionAttribute->newInstance()
+#1 {main}
+  thrown in %s on line %d
diff --git a/Zend/tests/first_class_callable/constexpr/autoload.phpt b/Zend/tests/first_class_callable/constexpr/autoload.phpt
new file mode 100644
index 0000000000000..2dd2561f9a369
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/autoload.phpt
@@ -0,0 +1,31 @@
+--TEST--
+FCC in const expression triggers autoloader.
+--FILE--
+<?php
+
+spl_autoload_register(static function ($class) {
+    echo "Autoloading {$class}", PHP_EOL;
+    eval(
+        <<<'EOT'
+            class AutoloadedClass {
+                public static function withStaticMethod() {
+                    echo "Called ", __METHOD__, PHP_EOL;
+                }
+            }
+            EOT
+    );
+});
+
+const Closure = AutoloadedClass::withStaticMethod(...);
+
+var_dump(Closure);
+(Closure)();
+
+?>
+--EXPECTF--
+Autoloading AutoloadedClass
+object(Closure)#%d (1) {
+  ["function"]=>
+  string(16) "withStaticMethod"
+}
+Called AutoloadedClass::withStaticMethod
diff --git a/Zend/tests/first_class_callable/constexpr/basic.phpt b/Zend/tests/first_class_callable/constexpr/basic.phpt
new file mode 100644
index 0000000000000..ce60cba1aa84f
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/basic.phpt
@@ -0,0 +1,22 @@
+--TEST--
+Allow defining FCC in const expressions.
+--FILE--
+<?php
+
+const Closure = strrev(...);
+
+var_dump(Closure);
+var_dump((Closure)("abc"));
+
+?>
+--EXPECTF--
+object(Closure)#%d (2) {
+  ["function"]=>
+  string(%d) "%s"
+  ["parameter"]=>
+  array(1) {
+    ["$string"]=>
+    string(10) "<required>"
+  }
+}
+string(3) "cba"
diff --git a/Zend/tests/first_class_callable/constexpr/case_insensitive.phpt b/Zend/tests/first_class_callable/constexpr/case_insensitive.phpt
new file mode 100644
index 0000000000000..1feaa718793de
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/case_insensitive.phpt
@@ -0,0 +1,22 @@
+--TEST--
+Allow defining FCC in const expressions with case-insensitive names.
+--FILE--
+<?php
+
+const Closure = StrRev(...);
+
+var_dump(Closure);
+var_dump((Closure)("abc"));
+
+?>
+--EXPECTF--
+object(Closure)#%d (2) {
+  ["function"]=>
+  string(%d) "%s"
+  ["parameter"]=>
+  array(1) {
+    ["$string"]=>
+    string(10) "<required>"
+  }
+}
+string(3) "cba"
diff --git a/Zend/tests/first_class_callable/constexpr/class_const.phpt b/Zend/tests/first_class_callable/constexpr/class_const.phpt
new file mode 100644
index 0000000000000..ab0ea29d50369
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/class_const.phpt
@@ -0,0 +1,24 @@
+--TEST--
+Allow defining FCC in class constants.
+--FILE--
+<?php
+
+class C {
+    const Closure = strrev(...);
+}
+
+var_dump(C::Closure);
+var_dump((C::Closure)("abc"));
+
+?>
+--EXPECTF--
+object(Closure)#%d (2) {
+  ["function"]=>
+  string(6) "strrev"
+  ["parameter"]=>
+  array(1) {
+    ["$string"]=>
+    string(10) "<required>"
+  }
+}
+string(3) "cba"
diff --git a/Zend/tests/first_class_callable/constexpr/complex_array.phpt b/Zend/tests/first_class_callable/constexpr/complex_array.phpt
new file mode 100644
index 0000000000000..388d09d056a42
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/complex_array.phpt
@@ -0,0 +1,39 @@
+--TEST--
+Allow defining FCC wrapped in an array in const expressions.
+--FILE--
+<?php
+
+const Closure = [strrev(...), strlen(...)];
+
+var_dump(Closure);
+
+foreach (Closure as $closure) {
+    var_dump($closure("abc"));
+}
+
+?>
+--EXPECTF--
+array(2) {
+  [0]=>
+  object(Closure)#%d (2) {
+    ["function"]=>
+    string(6) "strrev"
+    ["parameter"]=>
+    array(1) {
+      ["$string"]=>
+      string(10) "<required>"
+    }
+  }
+  [1]=>
+  object(Closure)#%d (2) {
+    ["function"]=>
+    string(6) "strlen"
+    ["parameter"]=>
+    array(1) {
+      ["$string"]=>
+      string(10) "<required>"
+    }
+  }
+}
+string(3) "cba"
+int(3)
diff --git a/Zend/tests/first_class_callable/constexpr/default_args.phpt b/Zend/tests/first_class_callable/constexpr/default_args.phpt
new file mode 100644
index 0000000000000..a35efc8961c17
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/default_args.phpt
@@ -0,0 +1,18 @@
+--TEST--
+FCC in default argument
+--FILE--
+<?php
+
+function test(
+    Closure $name = strrev(...)
+) {
+    var_dump($name("abc"));
+}
+
+test();
+test(strlen(...));
+
+?>
+--EXPECT--
+string(3) "cba"
+int(3)
diff --git a/Zend/tests/first_class_callable/constexpr/error_abstract.phpt b/Zend/tests/first_class_callable/constexpr/error_abstract.phpt
new file mode 100644
index 0000000000000..877f8f3c0b463
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/error_abstract.phpt
@@ -0,0 +1,20 @@
+--TEST--
+FCC in initializer errors for FCC on abstract method
+--FILE--
+<?php
+
+abstract class Foo {
+    abstract public static function myMethod(string $foo);
+}
+
+const Closure = Foo::myMethod(...);
+
+var_dump(Closure);
+(Closure)("abc");
+
+?>
+--EXPECTF--
+Fatal error: Uncaught Error: Cannot call abstract method Foo::myMethod() in %s:%d
+Stack trace:
+#0 {main}
+  thrown in %s on line %d
diff --git a/Zend/tests/first_class_callable/constexpr/error_dynamic_001.phpt b/Zend/tests/first_class_callable/constexpr/error_dynamic_001.phpt
new file mode 100644
index 0000000000000..44821cf6e60ad
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/error_dynamic_001.phpt
@@ -0,0 +1,12 @@
+--TEST--
+FCC in initializer errors for FCC on variable.
+--FILE--
+<?php
+
+const Closure = $foo(...);
+
+var_dump(Closure);
+
+?>
+--EXPECTF--
+Fatal error: Cannot use dynamic function name in constant expression in %s on line %d
diff --git a/Zend/tests/first_class_callable/constexpr/error_dynamic_002.phpt b/Zend/tests/first_class_callable/constexpr/error_dynamic_002.phpt
new file mode 100644
index 0000000000000..e373ff51620d5
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/error_dynamic_002.phpt
@@ -0,0 +1,12 @@
+--TEST--
+FCC in initializer errors for FCC on Closure.
+--FILE--
+<?php
+
+const Closure = (static function () { })(...);
+
+var_dump(Closure);
+
+?>
+--EXPECTF--
+Fatal error: Cannot use dynamic function name in constant expression in %s on line %d
diff --git a/Zend/tests/first_class_callable/constexpr/error_dynamic_003.phpt b/Zend/tests/first_class_callable/constexpr/error_dynamic_003.phpt
new file mode 100644
index 0000000000000..41090d89556f3
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/error_dynamic_003.phpt
@@ -0,0 +1,14 @@
+--TEST--
+FCC in initializer errors for FCC on Constant.
+--FILE--
+<?php
+
+const Name = 'strrev';
+
+const Closure = (Name)(...);
+
+var_dump(Closure);
+
+?>
+--EXPECTF--
+Fatal error: Cannot use dynamic function name in constant expression in %s on line %d
diff --git a/Zend/tests/first_class_callable/constexpr/error_dynamic_004.phpt b/Zend/tests/first_class_callable/constexpr/error_dynamic_004.phpt
new file mode 100644
index 0000000000000..f42c06cf86328
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/error_dynamic_004.phpt
@@ -0,0 +1,20 @@
+--TEST--
+FCC in initializer errors for FCC on 'static::'.
+--FILE--
+<?php
+
+class Foo {
+    public const Closure = static::myMethod(...);
+
+    public static function myMethod(string $foo) {
+        echo "Called ", __METHOD__, PHP_EOL;
+        var_dump($foo);
+    }
+}
+
+var_dump(Foo::Closure);
+(Foo::Closure)("abc");
+
+?>
+--EXPECTF--
+Fatal error: "static" is not allowed in compile-time constants in %s on line %d
diff --git a/Zend/tests/first_class_callable/constexpr/error_dynamic_005.phpt b/Zend/tests/first_class_callable/constexpr/error_dynamic_005.phpt
new file mode 100644
index 0000000000000..e13527444f1ca
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/error_dynamic_005.phpt
@@ -0,0 +1,12 @@
+--TEST--
+FCC in initializer errors for FCC on integer expression
+--FILE--
+<?php
+
+const Closure = (0)(...);
+
+var_dump(Closure);
+
+?>
+--EXPECTF--
+Fatal error: Illegal function name in %s on line %d
diff --git a/Zend/tests/first_class_callable/constexpr/error_instance_call.phpt b/Zend/tests/first_class_callable/constexpr/error_instance_call.phpt
new file mode 100644
index 0000000000000..cfee7c40b7844
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/error_instance_call.phpt
@@ -0,0 +1,20 @@
+--TEST--
+FCC in initializer errors for FCC on instance call.
+--FILE--
+<?php
+
+class Foo {
+    public function myMethod(string $foo) {
+        echo "Called ", __METHOD__, PHP_EOL;
+        var_dump($foo);
+    }
+}
+
+const Closure = (new Foo())->myMethod(...);
+
+var_dump(Closure);
+(Closure)("abc");
+
+?>
+--EXPECTF--
+Fatal error: Constant expression contains invalid operations in %s on line %d
diff --git a/Zend/tests/first_class_callable/constexpr/error_magic_callStatic.phpt b/Zend/tests/first_class_callable/constexpr/error_magic_callStatic.phpt
new file mode 100644
index 0000000000000..ea3d4822118ce
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/error_magic_callStatic.phpt
@@ -0,0 +1,23 @@
+--TEST--
+FCC in initializer errors for FCC on __callStatic() fallback.
+--FILE--
+<?php
+
+class Foo {
+    public static function __callStatic(string $name, array $foo) {
+        echo "Called ", __METHOD__, "({$name})", PHP_EOL;
+        var_dump($foo);
+    }
+}
+
+const Closure = Foo::myMethod(...);
+
+var_dump(Closure);
+(Closure)("abc");
+
+?>
+--EXPECTF--
+Fatal error: Uncaught Error: Creating a callable for the magic __callStatic() method is not supported in constant expressions in %s:%d
+Stack trace:
+#0 {main}
+  thrown in %s on line %d
diff --git a/Zend/tests/first_class_callable/constexpr/error_namespace_no_fallback_001.phpt b/Zend/tests/first_class_callable/constexpr/error_namespace_no_fallback_001.phpt
new file mode 100644
index 0000000000000..b80a222c2941d
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/error_namespace_no_fallback_001.phpt
@@ -0,0 +1,18 @@
+--TEST--
+FCC in initializer errors for missing function with FQN matching global function.
+--FILE--
+<?php
+
+namespace Foo;
+
+const Closure = \Foo\strrev(...);
+
+var_dump(Closure);
+var_dump((Closure)("abc"));
+
+?>
+--EXPECTF--
+Fatal error: Uncaught Error: Call to undefined function Foo\strrev() in %s:%d
+Stack trace:
+#0 {main}
+  thrown in %s on line %d
diff --git a/Zend/tests/first_class_callable/constexpr/error_namespace_no_fallback_002.phpt b/Zend/tests/first_class_callable/constexpr/error_namespace_no_fallback_002.phpt
new file mode 100644
index 0000000000000..62bc7e9e0b8bf
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/error_namespace_no_fallback_002.phpt
@@ -0,0 +1,18 @@
+--TEST--
+FCC in initializer errors for missing function with FQN matching global function.
+--FILE--
+<?php
+
+namespace Foo;
+
+const Closure = namespace\strrev(...);
+
+var_dump(Closure);
+var_dump((Closure)("abc"));
+
+?>
+--EXPECTF--
+Fatal error: Uncaught Error: Call to undefined function Foo\strrev() in %s:%d
+Stack trace:
+#0 {main}
+  thrown in %s on line %d
diff --git a/Zend/tests/first_class_callable/constexpr/error_static_call_instance_method.phpt b/Zend/tests/first_class_callable/constexpr/error_static_call_instance_method.phpt
new file mode 100644
index 0000000000000..9a6b27b232e6c
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/error_static_call_instance_method.phpt
@@ -0,0 +1,23 @@
+--TEST--
+FCC in initializer errors for static reference to instance method.
+--FILE--
+<?php
+
+class Foo {
+    public function myMethod(string $foo) {
+        echo "Called ", __METHOD__, PHP_EOL;
+        var_dump($foo);
+    }
+}
+
+const Closure = Foo::myMethod(...);
+
+var_dump(Closure);
+(Closure)("abc");
+
+?>
+--EXPECTF--
+Fatal error: Uncaught Error: Non-static method Foo::myMethod() cannot be called statically in %s:%d
+Stack trace:
+#0 {main}
+  thrown in %s on line %d
diff --git a/Zend/tests/first_class_callable/constexpr/error_static_call_trait_method_001.phpt b/Zend/tests/first_class_callable/constexpr/error_static_call_trait_method_001.phpt
new file mode 100644
index 0000000000000..efffa4a1d366a
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/error_static_call_trait_method_001.phpt
@@ -0,0 +1,31 @@
+--TEST--
+FCC in initializer errors for static reference to instance method.
+--FILE--
+<?php
+
+trait Foo {
+    public static function myMethod(string $foo) {
+        echo "Called ", __METHOD__, PHP_EOL;
+        var_dump($foo);
+    }
+}
+
+const Closure = Foo::myMethod(...);
+
+var_dump(Closure);
+(Closure)("abc");
+
+?>
+--EXPECTF--
+Deprecated: Calling static trait method Foo::myMethod is deprecated, it should only be called on a class using the trait in %s on line %d
+object(Closure)#%d (2) {
+  ["function"]=>
+  string(8) "myMethod"
+  ["parameter"]=>
+  array(1) {
+    ["$foo"]=>
+    string(10) "<required>"
+  }
+}
+Called Foo::myMethod
+string(3) "abc"
diff --git a/Zend/tests/first_class_callable/constexpr/error_static_call_trait_method_002.phpt b/Zend/tests/first_class_callable/constexpr/error_static_call_trait_method_002.phpt
new file mode 100644
index 0000000000000..d36f7c97651e0
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/error_static_call_trait_method_002.phpt
@@ -0,0 +1,31 @@
+--TEST--
+FCC in initializer errors for static reference to instance method (Exception).
+--FILE--
+<?php
+
+set_error_handler(function (int $errno, string $errstr, ?string $errfile = null, ?int $errline = null) {
+    throw new \ErrorException($errstr, 0, $errno, $errfile, $errline);
+});
+
+trait Foo {
+    public static function myMethod(string $foo) {
+        echo "Called ", __METHOD__, PHP_EOL;
+        var_dump($foo);
+    }
+}
+
+function foo(Closure $c = Foo::myMethod(...)) {
+    var_dump($c);
+    $c("abc");  
+}
+
+try {
+    foo();
+} catch (ErrorException $e) {
+    echo "Caught: ", $e->getMessage(), PHP_EOL;
+}
+
+
+?>
+--EXPECT--
+Caught: Calling static trait method Foo::myMethod is deprecated, it should only be called on a class using the trait
diff --git a/Zend/tests/first_class_callable/constexpr/error_unknown_class.phpt b/Zend/tests/first_class_callable/constexpr/error_unknown_class.phpt
new file mode 100644
index 0000000000000..39ce1736ddecd
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/error_unknown_class.phpt
@@ -0,0 +1,15 @@
+--TEST--
+FCC in initializer errors for missing class.
+--FILE--
+<?php
+
+const Closure = ThisClassNotDoesExist::thisMethodIsNotRelevant(...);
+
+var_dump(Closure);
+
+?>
+--EXPECTF--
+Fatal error: Uncaught Error: Class "ThisClassNotDoesExist" not found in %s:%d
+Stack trace:
+#0 {main}
+  thrown in %s on line %d
diff --git a/Zend/tests/first_class_callable/constexpr/error_unknown_function.phpt b/Zend/tests/first_class_callable/constexpr/error_unknown_function.phpt
new file mode 100644
index 0000000000000..38b291d9907ad
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/error_unknown_function.phpt
@@ -0,0 +1,15 @@
+--TEST--
+FCC in initializer errors for missing function.
+--FILE--
+<?php
+
+const Closure = this_function_does_not_exist(...);
+
+var_dump(Closure);
+
+?>
+--EXPECTF--
+Fatal error: Uncaught Error: Call to undefined function this_function_does_not_exist() in %s:%d
+Stack trace:
+#0 {main}
+  thrown in %s on line %d
diff --git a/Zend/tests/first_class_callable/constexpr/error_unknown_method.phpt b/Zend/tests/first_class_callable/constexpr/error_unknown_method.phpt
new file mode 100644
index 0000000000000..345d67ee74dae
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/error_unknown_method.phpt
@@ -0,0 +1,17 @@
+--TEST--
+FCC in initializer errors for missing method.
+--FILE--
+<?php
+
+class ThisClassDoesExist { }
+
+const Closure = ThisClassDoesExist::thisMethodDoesNotExist(...);
+
+var_dump(Closure);
+
+?>
+--EXPECTF--
+Fatal error: Uncaught Error: Call to undefined method ThisClassDoesExist::thisMethodDoesNotExist() in %s:%d
+Stack trace:
+#0 {main}
+  thrown in %s on line %d
diff --git a/Zend/tests/first_class_callable/constexpr/namespace_001.phpt b/Zend/tests/first_class_callable/constexpr/namespace_001.phpt
new file mode 100644
index 0000000000000..f920844957894
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/namespace_001.phpt
@@ -0,0 +1,24 @@
+--TEST--
+Allow defining FCC in const expressions in a namespace.
+--FILE--
+<?php
+
+namespace Foo;
+
+const Closure = \strrev(...);
+
+var_dump(Closure);
+var_dump((Closure)("abc"));
+
+?>
+--EXPECTF--
+object(Closure)#%d (2) {
+  ["function"]=>
+  string(%d) "%s"
+  ["parameter"]=>
+  array(1) {
+    ["$string"]=>
+    string(10) "<required>"
+  }
+}
+string(3) "cba"
diff --git a/Zend/tests/first_class_callable/constexpr/namespace_002.phpt b/Zend/tests/first_class_callable/constexpr/namespace_002.phpt
new file mode 100644
index 0000000000000..17d70ad511af7
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/namespace_002.phpt
@@ -0,0 +1,24 @@
+--TEST--
+Allow defining FCC in const expressions in a namespace with global function fallback.
+--FILE--
+<?php
+
+namespace Foo;
+
+const Closure = strrev(...);
+
+var_dump(Closure);
+var_dump((Closure)("abc"));
+
+?>
+--EXPECTF--
+object(Closure)#%d (2) {
+  ["function"]=>
+  string(%d) "%s"
+  ["parameter"]=>
+  array(1) {
+    ["$string"]=>
+    string(10) "<required>"
+  }
+}
+string(3) "cba"
diff --git a/Zend/tests/first_class_callable/constexpr/namespace_003.phpt b/Zend/tests/first_class_callable/constexpr/namespace_003.phpt
new file mode 100644
index 0000000000000..2fe1d45296ce7
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/namespace_003.phpt
@@ -0,0 +1,28 @@
+--TEST--
+Allow defining FCC in const expressions in a namespace with function matching a global function.
+--FILE--
+<?php
+
+namespace Foo;
+
+function strrev(string $value) {
+    return 'not the global one';
+}
+
+const Closure = strrev(...);
+
+var_dump(Closure);
+var_dump((Closure)("abc"));
+
+?>
+--EXPECTF--
+object(Closure)#%d (2) {
+  ["function"]=>
+  string(%d) "%s"
+  ["parameter"]=>
+  array(1) {
+    ["$value"]=>
+    string(10) "<required>"
+  }
+}
+string(18) "not the global one"
diff --git a/Zend/tests/first_class_callable/constexpr/namespace_004.phpt b/Zend/tests/first_class_callable/constexpr/namespace_004.phpt
new file mode 100644
index 0000000000000..0fc23422199d5
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/namespace_004.phpt
@@ -0,0 +1,68 @@
+--TEST--
+Allow defining FCC in const expressions in a namespace with function matching a global function later.
+--FILE--
+<?php
+
+namespace Foo;
+
+function foo(\Closure $c = strrev(...)) {
+    $d = strrev(...);
+    var_dump($c);
+    var_dump($c("abc"));
+    var_dump($d);
+    var_dump($d("abc"));
+}
+
+
+foo();
+
+if (random_int(1, 2) > 0) {
+    function strrev(string $value) {
+        return 'not the global one';
+    }
+}
+
+foo();
+
+?>
+--EXPECTF--
+object(Closure)#1 (2) {
+  ["function"]=>
+  string(6) "strrev"
+  ["parameter"]=>
+  array(1) {
+    ["$string"]=>
+    string(10) "<required>"
+  }
+}
+string(3) "cba"
+object(Closure)#2 (2) {
+  ["function"]=>
+  string(6) "strrev"
+  ["parameter"]=>
+  array(1) {
+    ["$string"]=>
+    string(10) "<required>"
+  }
+}
+string(3) "cba"
+object(Closure)#2 (2) {
+  ["function"]=>
+  string(6) "strrev"
+  ["parameter"]=>
+  array(1) {
+    ["$string"]=>
+    string(10) "<required>"
+  }
+}
+string(3) "cba"
+object(Closure)#1 (2) {
+  ["function"]=>
+  string(6) "strrev"
+  ["parameter"]=>
+  array(1) {
+    ["$string"]=>
+    string(10) "<required>"
+  }
+}
+string(3) "cba"
diff --git a/Zend/tests/first_class_callable/constexpr/property_initializer.phpt b/Zend/tests/first_class_callable/constexpr/property_initializer.phpt
new file mode 100644
index 0000000000000..53cae06216bd1
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/property_initializer.phpt
@@ -0,0 +1,26 @@
+--TEST--
+FCC in property initializer
+--FILE--
+<?php
+
+class C {
+    public Closure $d = strrev(...);
+}
+
+$c = new C();
+var_dump($c->d);
+var_dump(($c->d)("abc"));
+
+
+?>
+--EXPECTF--
+object(Closure)#%d (2) {
+  ["function"]=>
+  string(6) "strrev"
+  ["parameter"]=>
+  array(1) {
+    ["$string"]=>
+    string(10) "<required>"
+  }
+}
+string(3) "cba"
diff --git a/Zend/tests/first_class_callable/constexpr/property_initializer_scope_001.phpt b/Zend/tests/first_class_callable/constexpr/property_initializer_scope_001.phpt
new file mode 100644
index 0000000000000..67428d1c6470e
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/property_initializer_scope_001.phpt
@@ -0,0 +1,32 @@
+--TEST--
+FCC in property initializer may access private methods.
+--FILE--
+<?php
+
+class C {
+    public Closure $d = C::myMethod(...);
+
+    private static function myMethod(string $foo) {
+        echo "Called ", __METHOD__, PHP_EOL;
+        var_dump($foo);
+    }
+}
+
+$c = new C();
+var_dump($c->d);
+var_dump(($c->d)("abc"));
+
+?>
+--EXPECTF--
+object(Closure)#%d (2) {
+  ["function"]=>
+  string(11) "C::myMethod"
+  ["parameter"]=>
+  array(1) {
+    ["$foo"]=>
+    string(10) "<required>"
+  }
+}
+Called C::myMethod
+string(3) "abc"
+NULL
diff --git a/Zend/tests/first_class_callable/constexpr/property_initializer_scope_002.phpt b/Zend/tests/first_class_callable/constexpr/property_initializer_scope_002.phpt
new file mode 100644
index 0000000000000..ecee256012ece
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/property_initializer_scope_002.phpt
@@ -0,0 +1,27 @@
+--TEST--
+FCC in property initializer may not access unrelated private methods.
+--FILE--
+<?php
+
+class E {
+    private static function myMethod(string $foo) {
+        echo "Called ", __METHOD__, PHP_EOL;
+        var_dump($foo);
+    }
+}
+
+class C {
+  public Closure $d = E::myMethod(...);
+}
+
+$c = new C();
+var_dump($c->d);
+var_dump(($c->d)("abc"));
+
+?>
+--EXPECTF--
+Fatal error: Uncaught Error: Call to private method E::myMethod() from scope C in %s:%d
+Stack trace:
+#0 %s(%d): [constant expression]()
+#1 {main}
+  thrown in %s on line %d
diff --git a/Zend/tests/first_class_callable/constexpr/property_initializer_scope_003.phpt b/Zend/tests/first_class_callable/constexpr/property_initializer_scope_003.phpt
new file mode 100644
index 0000000000000..3959efbd16a05
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/property_initializer_scope_003.phpt
@@ -0,0 +1,35 @@
+--TEST--
+FCC in property initializer may access protected methods of parent.
+--FILE--
+<?php
+
+class P {
+    protected static function myMethod(string $foo) {
+        echo "Called ", __METHOD__, PHP_EOL;
+        var_dump($foo);
+    }
+}
+
+
+class C extends P {
+    public Closure $d = self::myMethod(...);
+}
+
+$c = new C();
+var_dump($c->d);
+var_dump(($c->d)("abc"));
+
+?>
+--EXPECTF--
+object(Closure)#%d (2) {
+  ["function"]=>
+  string(11) "C::myMethod"
+  ["parameter"]=>
+  array(1) {
+    ["$foo"]=>
+    string(10) "<required>"
+  }
+}
+Called P::myMethod
+string(3) "abc"
+NULL
diff --git a/Zend/tests/first_class_callable/constexpr/static_call.phpt b/Zend/tests/first_class_callable/constexpr/static_call.phpt
new file mode 100644
index 0000000000000..26761a041a4cc
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/static_call.phpt
@@ -0,0 +1,30 @@
+--TEST--
+Allow defining FCC for static methods in const expressions.
+--FILE--
+<?php
+
+class Foo {
+    public static function myMethod(string $foo) {
+        echo "Called ", __METHOD__, PHP_EOL;
+        var_dump($foo);
+    }
+}
+
+const Closure = Foo::myMethod(...);
+
+var_dump(Closure);
+(Closure)("abc");
+
+?>
+--EXPECTF--
+object(Closure)#%d (2) {
+  ["function"]=>
+  string(8) "myMethod"
+  ["parameter"]=>
+  array(1) {
+    ["$foo"]=>
+    string(10) "<required>"
+  }
+}
+Called Foo::myMethod
+string(3) "abc"
diff --git a/Zend/tests/first_class_callable/constexpr/static_call_self.phpt b/Zend/tests/first_class_callable/constexpr/static_call_self.phpt
new file mode 100644
index 0000000000000..6cbf1726caa91
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/static_call_self.phpt
@@ -0,0 +1,30 @@
+--TEST--
+Allow defining FCC for static methods referenced by 'self::' in const expressions.
+--FILE--
+<?php
+
+class Foo {
+    public const Closure = self::myMethod(...);
+
+    public static function myMethod(string $foo) {
+        echo "Called ", __METHOD__, PHP_EOL;
+        var_dump($foo);
+    }
+}
+
+var_dump(Foo::Closure);
+(Foo::Closure)("abc");
+
+?>
+--EXPECTF--
+object(Closure)#%d (2) {
+  ["function"]=>
+  string(13) "Foo::myMethod"
+  ["parameter"]=>
+  array(1) {
+    ["$foo"]=>
+    string(10) "<required>"
+  }
+}
+Called Foo::myMethod
+string(3) "abc"
diff --git a/Zend/tests/first_class_callable/constexpr/static_property_initializer.phpt b/Zend/tests/first_class_callable/constexpr/static_property_initializer.phpt
new file mode 100644
index 0000000000000..d46b88aae9be0
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/static_property_initializer.phpt
@@ -0,0 +1,25 @@
+--TEST--
+FCC in static property initializer
+--FILE--
+<?php
+
+class C {
+    public static Closure $d = strrev(...);
+}
+
+var_dump(C::$d);
+var_dump((C::$d)("abc"));
+
+
+?>
+--EXPECTF--
+object(Closure)#%d (2) {
+  ["function"]=>
+  string(6) "strrev"
+  ["parameter"]=>
+  array(1) {
+    ["$string"]=>
+    string(10) "<required>"
+  }
+}
+string(3) "cba"
diff --git a/Zend/tests/first_class_callable/constexpr/userland.phpt b/Zend/tests/first_class_callable/constexpr/userland.phpt
new file mode 100644
index 0000000000000..6ead1e51ff31c
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/userland.phpt
@@ -0,0 +1,28 @@
+--TEST--
+Allow defining FCC for userland functions in const expressions.
+--FILE--
+<?php
+
+function my_function(string $foo) {
+    echo "Called ", __FUNCTION__, PHP_EOL;
+    var_dump($foo);
+}
+
+const Closure = my_function(...);
+
+var_dump(Closure);
+(Closure)("abc");
+
+?>
+--EXPECTF--
+object(Closure)#%d (2) {
+  ["function"]=>
+  string(11) "my_function"
+  ["parameter"]=>
+  array(1) {
+    ["$foo"]=>
+    string(10) "<required>"
+  }
+}
+Called my_function
+string(3) "abc"
diff --git a/Zend/zend_ast.c b/Zend/zend_ast.c
index d4f71ee5ad99d..8b0a66fda8096 100644
--- a/Zend/zend_ast.c
+++ b/Zend/zend_ast.c
@@ -54,6 +54,18 @@ ZEND_API zend_ast * ZEND_FASTCALL zend_ast_create_znode(znode *node) {
 	return (zend_ast *) ast;
 }
 
+ZEND_API zend_ast * ZEND_FASTCALL zend_ast_create_fcc(void) {
+	zend_ast_fcc *ast;
+
+	ast = zend_ast_alloc(sizeof(zend_ast_fcc));
+	ast->kind = ZEND_AST_CALLABLE_CONVERT;
+	ast->attr = 0;
+	ast->lineno = CG(zend_lineno);
+	ZEND_MAP_PTR_INIT(ast->fptr, NULL);
+
+	return (zend_ast *) ast;
+}
+
 static zend_always_inline zend_ast * zend_ast_create_zval_int(zval *zv, uint32_t attr, uint32_t lineno) {
 	zend_ast_zval *ast;
 
@@ -1002,6 +1014,111 @@ ZEND_API zend_result ZEND_FASTCALL zend_ast_evaluate_inner(
 			}
 			return SUCCESS;
 		}
+		case ZEND_AST_CALL:
+		case ZEND_AST_STATIC_CALL:
+		{
+			zend_function *fptr;
+			switch (ast->kind) {
+				case ZEND_AST_CALL: {
+					ZEND_ASSERT(ast->child[1]->kind == ZEND_AST_CALLABLE_CONVERT);
+					zend_ast_fcc *fcc_ast = (zend_ast_fcc*)ast->child[1];
+					fptr = ZEND_MAP_PTR_GET(fcc_ast->fptr);
+
+					if (!fptr) {
+						zend_string *function_name = zend_ast_get_str(ast->child[0]);
+						zend_string *function_name_lc = zend_string_tolower(function_name);
+						fptr = zend_fetch_function(function_name_lc);
+						if (!fptr && ast->child[0]->attr != ZEND_NAME_FQ) {
+							const char *backslash = zend_memrchr(ZSTR_VAL(function_name_lc), '\\', ZSTR_LEN(function_name_lc));
+							if (backslash) {
+								fptr = zend_fetch_function_str(backslash + 1, ZSTR_LEN(function_name_lc) - (backslash - ZSTR_VAL(function_name_lc) + 1));
+							}
+						}
+						zend_string_release(function_name_lc);
+						if (!fptr) {
+							zend_throw_error(NULL, "Call to undefined function %s()", ZSTR_VAL(function_name));
+							return FAILURE;
+						}
+
+						ZEND_MAP_PTR_SET(fcc_ast->fptr, fptr);
+					}
+
+					break;
+				}
+				case ZEND_AST_STATIC_CALL: {
+					ZEND_ASSERT(ast->child[2]->kind == ZEND_AST_CALLABLE_CONVERT);
+					zend_ast_fcc *fcc_ast = (zend_ast_fcc*)ast->child[2];
+
+					fptr = ZEND_MAP_PTR_GET(fcc_ast->fptr);
+
+					if (!fptr) {
+						zend_class_entry *ce = zend_ast_fetch_class(ast->child[0], scope);
+						if (!ce) {
+							return FAILURE;
+						}
+						zend_string *method_name = zend_ast_get_str(ast->child[1]);
+						if (ce->get_static_method) {
+							fptr = ce->get_static_method(ce, method_name);
+						} else {
+							fptr = zend_hash_find_ptr_lc(&ce->function_table, method_name);
+							if (fptr) {
+								if (!(fptr->common.fn_flags & ZEND_ACC_PUBLIC)) {
+									if (UNEXPECTED(fptr->common.scope != scope)) {
+										if (
+											UNEXPECTED(fptr->op_array.fn_flags & ZEND_ACC_PRIVATE)
+											|| UNEXPECTED(!zend_check_protected(zend_get_function_root_class(fptr), scope))
+										) {
+											if (ce->__callstatic) {
+												zend_throw_error(NULL, "Creating a callable for the magic __callStatic() method is not supported in constant expressions");
+											} else {
+												zend_bad_method_call(fptr, method_name, scope);
+											}
+
+											return FAILURE;
+										}
+									}
+								}
+							} else {
+								if (ce->__callstatic) {
+									zend_throw_error(NULL, "Creating a callable for the magic __callStatic() method is not supported in constant expressions");
+								} else {
+									zend_undefined_method(ce, method_name);
+								}
+
+								return FAILURE;
+							}
+						}
+
+						if (!(fptr->common.fn_flags & ZEND_ACC_STATIC)) {
+							zend_non_static_method_call(fptr);
+							
+							return FAILURE;
+						}
+						if ((fptr->common.fn_flags & ZEND_ACC_ABSTRACT)) {
+							zend_abstract_method_call(fptr);
+							
+							return FAILURE;
+						} else if (fptr->common.scope->ce_flags & ZEND_ACC_TRAIT) {
+							zend_error(E_DEPRECATED,
+								"Calling static trait method %s::%s is deprecated, "
+								"it should only be called on a class using the trait",
+								ZSTR_VAL(fptr->common.scope->name), ZSTR_VAL(fptr->common.function_name));
+							if (EG(exception)) {
+								return FAILURE;
+							}
+						}
+
+						ZEND_MAP_PTR_SET(fcc_ast->fptr, fptr);
+					}
+
+					break;
+				}
+			}
+
+			zend_create_fake_closure(result, fptr, scope, scope, NULL);
+
+			return SUCCESS;
+		}
 		case ZEND_AST_OP_ARRAY:
 		{
 			zend_function *func = (zend_function *)zend_ast_get_op_array(ast)->op_array;
@@ -1092,6 +1209,8 @@ static size_t ZEND_FASTCALL zend_ast_tree_size(zend_ast *ast)
 		size = sizeof(zend_ast_zval);
 	} else if (ast->kind == ZEND_AST_OP_ARRAY) {
 		size = sizeof(zend_ast_op_array);
+	} else if (ast->kind == ZEND_AST_CALLABLE_CONVERT) {
+		size = sizeof(zend_ast_fcc);
 	} else if (zend_ast_is_list(ast)) {
 		uint32_t i;
 		zend_ast_list *list = zend_ast_get_list(ast);
@@ -1159,6 +1278,14 @@ static void* ZEND_FASTCALL zend_ast_tree_copy(zend_ast *ast, void *buf)
 		new->lineno = old->lineno;
 		new->op_array = old->op_array;
 		buf = (void*)((char*)buf + sizeof(zend_ast_op_array));
+	} else if (ast->kind == ZEND_AST_CALLABLE_CONVERT) {
+		zend_ast_fcc *old = (zend_ast_fcc*)ast;
+		zend_ast_fcc *new = (zend_ast_fcc*)buf;
+		new->kind = old->kind;
+		new->attr = old->attr;
+		new->lineno = old->lineno;
+		ZEND_MAP_PTR_INIT(new->fptr, ZEND_MAP_PTR(old->fptr));
+		buf = (void*)((char*)buf + sizeof(zend_ast_fcc));
 	} else if (zend_ast_is_decl(ast)) {
 		/* Not implemented. */
 		ZEND_UNREACHABLE();
diff --git a/Zend/zend_ast.h b/Zend/zend_ast.h
index d3689af53ff7e..d0dad8490c4e3 100644
--- a/Zend/zend_ast.h
+++ b/Zend/zend_ast.h
@@ -22,6 +22,7 @@
 #define ZEND_AST_H
 
 #include "zend_types.h"
+#include "zend_map_ptr.h"
 
 #ifndef ZEND_AST_SPEC
 # define ZEND_AST_SPEC 1
@@ -227,6 +228,13 @@ typedef struct _zend_ast_decl {
 	zend_ast *child[5];
 } zend_ast_decl;
 
+typedef struct _zend_ast_fcc {
+	zend_ast_kind kind; /* Type of the node (ZEND_AST_* enum constant) */
+	zend_ast_attr attr; /* Additional attribute, use depending on node type */
+	uint32_t lineno;    /* Line number */
+	ZEND_MAP_PTR_DEF(zend_function *, fptr);
+} zend_ast_fcc;
+
 typedef void (*zend_ast_process_t)(zend_ast *ast);
 extern ZEND_API zend_ast_process_t zend_ast_process;
 
@@ -318,6 +326,8 @@ ZEND_API zend_ast *zend_ast_create_decl(
 	zend_string *name, zend_ast *child0, zend_ast *child1, zend_ast *child2, zend_ast *child3, zend_ast *child4
 );
 
+ZEND_API zend_ast * ZEND_FASTCALL zend_ast_create_fcc(void);
+
 typedef struct {
 	bool had_side_effects;
 } zend_ast_evaluate_ctx;
diff --git a/Zend/zend_compile.c b/Zend/zend_compile.c
index b4dea55414ffc..9711d05a1b1c6 100644
--- a/Zend/zend_compile.c
+++ b/Zend/zend_compile.c
@@ -11099,7 +11099,8 @@ static bool zend_is_allowed_in_const_expr(zend_ast_kind kind) /* {{{ */
 		|| kind == ZEND_AST_NEW || kind == ZEND_AST_ARG_LIST
 		|| kind == ZEND_AST_NAMED_ARG
 		|| kind == ZEND_AST_PROP || kind == ZEND_AST_NULLSAFE_PROP
-		|| kind == ZEND_AST_CLOSURE;
+		|| kind == ZEND_AST_CLOSURE
+		|| kind == ZEND_AST_CALL || kind == ZEND_AST_STATIC_CALL || kind == ZEND_AST_CALLABLE_CONVERT;
 }
 /* }}} */
 
@@ -11208,9 +11209,8 @@ static void zend_compile_const_expr_magic_const(zend_ast **ast_ptr) /* {{{ */
 }
 /* }}} */
 
-static void zend_compile_const_expr_new(zend_ast **ast_ptr)
+static void zend_compile_const_expr_class_reference(zend_ast *class_ast)
 {
-	zend_ast *class_ast = (*ast_ptr)->child[0];
 	if (class_ast->kind == ZEND_AST_CLASS) {
 		zend_error_noreturn(E_COMPILE_ERROR,
 			"Cannot use anonymous class in constant expression");
@@ -11233,6 +11233,12 @@ static void zend_compile_const_expr_new(zend_ast **ast_ptr)
 	class_ast->attr = fetch_type << ZEND_CONST_EXPR_NEW_FETCH_TYPE_SHIFT;
 }
 
+static void zend_compile_const_expr_new(zend_ast **ast_ptr)
+{
+	zend_ast *class_ast = (*ast_ptr)->child[0];
+	zend_compile_const_expr_class_reference(class_ast);
+}
+
 static void zend_compile_const_expr_closure(zend_ast **ast_ptr)
 {
 	zend_ast_decl *closure_ast = (zend_ast_decl *) *ast_ptr;
@@ -11253,6 +11259,58 @@ static void zend_compile_const_expr_closure(zend_ast **ast_ptr)
 	*ast_ptr = zend_ast_create_op_array(op);
 }
 
+static void zend_compile_const_expr_fcc(zend_ast **ast_ptr)
+{
+	zend_ast **args_ast;
+	switch ((*ast_ptr)->kind) {
+		case ZEND_AST_CALL:
+			args_ast = &(*ast_ptr)->child[1];
+			break;
+		case ZEND_AST_STATIC_CALL:
+			args_ast = &(*ast_ptr)->child[2];
+			break;
+		EMPTY_SWITCH_DEFAULT_CASE();
+	}
+	if ((*args_ast)->kind != ZEND_AST_CALLABLE_CONVERT) {
+		zend_error_noreturn(E_COMPILE_ERROR, "Constant expression contains invalid operations");
+	}
+	ZEND_MAP_PTR_NEW(((zend_ast_fcc *)*args_ast)->fptr);
+
+	switch ((*ast_ptr)->kind) {
+		case ZEND_AST_CALL: {
+			zend_ast *name_ast = (*ast_ptr)->child[0];
+			if (name_ast->kind != ZEND_AST_ZVAL) {
+				zend_error_noreturn(E_COMPILE_ERROR, "Cannot use dynamic function name in constant expression");
+			}
+			zval *name_ast_zv = zend_ast_get_zval(name_ast);
+			if (Z_TYPE_P(name_ast_zv) != IS_STRING) {
+				zend_error_noreturn(E_COMPILE_ERROR, "Illegal function name");
+			}
+			bool is_fully_qualified;
+			zend_string *name = zend_resolve_function_name(Z_STR_P(name_ast_zv), name_ast->attr, &is_fully_qualified);
+			zval_ptr_dtor_nogc(name_ast_zv);
+			ZVAL_STR(name_ast_zv, name);
+			if (is_fully_qualified) {
+				name_ast->attr = ZEND_NAME_FQ;
+			}
+			break;
+		}
+		case ZEND_AST_STATIC_CALL: {
+			zend_ast *class_ast = (*ast_ptr)->child[0];
+			zend_compile_const_expr_class_reference(class_ast);
+			zend_ast *method_ast = (*ast_ptr)->child[1];
+			if (method_ast->kind != ZEND_AST_ZVAL) {
+				zend_error_noreturn(E_COMPILE_ERROR, "Cannot use dynamic method name in constant expression");
+			}
+			if (Z_TYPE_P(zend_ast_get_zval(method_ast)) != IS_STRING) {
+				zend_error_noreturn(E_COMPILE_ERROR, "Illegal method name");
+			}
+			break;
+		}
+		EMPTY_SWITCH_DEFAULT_CASE();
+	}
+}
+
 static void zend_compile_const_expr_args(zend_ast **ast_ptr)
 {
 	zend_ast_list *list = zend_ast_get_list(*ast_ptr);
@@ -11319,6 +11377,10 @@ static void zend_compile_const_expr(zend_ast **ast_ptr, void *context) /* {{{ */
 			zend_compile_const_expr_closure(ast_ptr);
 			/* Return, because we do not want to traverse the children. */
 			return;
+		case ZEND_AST_CALL:
+		case ZEND_AST_STATIC_CALL:
+			zend_compile_const_expr_fcc(ast_ptr);
+			break;
 	}
 
 	zend_ast_apply(ast, zend_compile_const_expr, context);
diff --git a/Zend/zend_execute.c b/Zend/zend_execute.c
index 9742eaa190165..0c24aac48470a 100644
--- a/Zend/zend_execute.c
+++ b/Zend/zend_execute.c
@@ -2448,7 +2448,7 @@ ZEND_API ZEND_COLD zval* ZEND_FASTCALL zend_undefined_index_write(HashTable *ht,
 	return retval;
 }
 
-static zend_never_inline ZEND_COLD void ZEND_FASTCALL zend_undefined_method(const zend_class_entry *ce, const zend_string *method)
+ZEND_API zend_never_inline ZEND_COLD void ZEND_FASTCALL zend_undefined_method(const zend_class_entry *ce, const zend_string *method)
 {
 	zend_throw_error(NULL, "Call to undefined method %s::%s()", ZSTR_VAL(ce->name), ZSTR_VAL(method));
 }
diff --git a/Zend/zend_execute.h b/Zend/zend_execute.h
index 1734269186116..3b8ed89ec4f38 100644
--- a/Zend/zend_execute.h
+++ b/Zend/zend_execute.h
@@ -447,6 +447,7 @@ ZEND_API void zend_cleanup_unfinished_execution(zend_execute_data *execute_data,
 ZEND_API ZEND_ATTRIBUTE_DEPRECATED HashTable *zend_unfinished_execution_gc(zend_execute_data *execute_data, zend_execute_data *call, zend_get_gc_buffer *gc_buffer);
 ZEND_API HashTable *zend_unfinished_execution_gc_ex(zend_execute_data *execute_data, zend_execute_data *call, zend_get_gc_buffer *gc_buffer, bool suspended_by_yield);
 ZEND_API zval* ZEND_FASTCALL zend_fetch_static_property(zend_execute_data *ex, int fetch_type);
+ZEND_API zend_never_inline ZEND_COLD void ZEND_FASTCALL zend_undefined_method(const zend_class_entry *ce, const zend_string *method);
 ZEND_API void ZEND_FASTCALL zend_non_static_method_call(const zend_function *fbc);
 
 ZEND_API void zend_frameless_observed_call(zend_execute_data *execute_data);
diff --git a/Zend/zend_language_parser.y b/Zend/zend_language_parser.y
index d2a29e670d8bf..c671b3a295e5c 100644
--- a/Zend/zend_language_parser.y
+++ b/Zend/zend_language_parser.y
@@ -896,7 +896,7 @@ return_type:
 argument_list:
 		'(' ')'	{ $$ = zend_ast_create_list(0, ZEND_AST_ARG_LIST); }
 	|	'(' non_empty_argument_list possible_comma ')' { $$ = $2; }
-	|	'(' T_ELLIPSIS ')' { $$ = zend_ast_create(ZEND_AST_CALLABLE_CONVERT); }
+	|	'(' T_ELLIPSIS ')' { $$ = zend_ast_create_fcc(); }
 ;
 
 non_empty_argument_list:
diff --git a/Zend/zend_object_handlers.c b/Zend/zend_object_handlers.c
index cdcdd1622746f..b6d17a1149d48 100644
--- a/Zend/zend_object_handlers.c
+++ b/Zend/zend_object_handlers.c
@@ -1748,7 +1748,7 @@ static zend_always_inline zend_function *zend_get_user_call_function(zend_class_
 }
 /* }}} */
 
-static ZEND_COLD zend_never_inline void zend_bad_method_call(zend_function *fbc, zend_string *method_name, zend_class_entry *scope) /* {{{ */
+ZEND_API ZEND_COLD zend_never_inline void zend_bad_method_call(zend_function *fbc, zend_string *method_name, zend_class_entry *scope) /* {{{ */
 {
 	zend_throw_error(NULL, "Call to %s method %s::%s() from %s%s",
 		zend_visibility_string(fbc->common.fn_flags), ZEND_FN_SCOPE_NAME(fbc), ZSTR_VAL(method_name),
@@ -1758,7 +1758,7 @@ static ZEND_COLD zend_never_inline void zend_bad_method_call(zend_function *fbc,
 }
 /* }}} */
 
-static ZEND_COLD zend_never_inline void zend_abstract_method_call(zend_function *fbc) /* {{{ */
+ZEND_API ZEND_COLD zend_never_inline void zend_abstract_method_call(zend_function *fbc) /* {{{ */
 {
 	zend_throw_error(NULL, "Cannot call abstract method %s::%s()",
 		ZSTR_VAL(fbc->common.scope->name), ZSTR_VAL(fbc->common.function_name));
diff --git a/Zend/zend_object_handlers.h b/Zend/zend_object_handlers.h
index 1f2580a5adcaa..130e84b5c5874 100644
--- a/Zend/zend_object_handlers.h
+++ b/Zend/zend_object_handlers.h
@@ -272,6 +272,8 @@ ZEND_API int zend_std_compare_objects(zval *o1, zval *o2);
 ZEND_API zend_result zend_std_get_closure(zend_object *obj, zend_class_entry **ce_ptr, zend_function **fptr_ptr, zend_object **obj_ptr, bool check_only);
 /* Use zend_std_get_properties_ex() */
 ZEND_API HashTable *rebuild_object_properties_internal(zend_object *zobj);
+ZEND_API ZEND_COLD zend_never_inline void zend_bad_method_call(zend_function *fbc, zend_string *method_name, zend_class_entry *scope);
+ZEND_API ZEND_COLD zend_never_inline void zend_abstract_method_call(zend_function *fbc);
 
 static zend_always_inline HashTable *zend_std_get_properties_ex(zend_object *object)
 {
diff --git a/ext/opcache/jit/zend_jit_helpers.c b/ext/opcache/jit/zend_jit_helpers.c
index 56b8b2d69cac2..9fa0d4d85805c 100644
--- a/ext/opcache/jit/zend_jit_helpers.c
+++ b/ext/opcache/jit/zend_jit_helpers.c
@@ -122,11 +122,6 @@ static ZEND_COLD void ZEND_FASTCALL zend_jit_invalid_method_call_tmp(zval *objec
 	zval_ptr_dtor_nogc(EX_VAR(opline->op1.var));
 }
 
-static zend_never_inline ZEND_COLD void ZEND_FASTCALL zend_undefined_method(const zend_class_entry *ce, const zend_string *method)
-{
-	zend_throw_error(NULL, "Call to undefined method %s::%s()", ZSTR_VAL(ce->name), ZSTR_VAL(method));
-}
-
 static void ZEND_FASTCALL zend_jit_unref_helper(zval *zv)
 {
 	zend_reference *ref;
diff --git a/ext/opcache/zend_file_cache.c b/ext/opcache/zend_file_cache.c
index 2a13f751ce3fa..e612dcd80748b 100644
--- a/ext/opcache/zend_file_cache.c
+++ b/ext/opcache/zend_file_cache.c
@@ -366,6 +366,9 @@ static void zend_file_cache_serialize_ast(zend_ast                 *ast,
 	} else if (ast->kind == ZEND_AST_OP_ARRAY) {
 		/* The op_array itself will be serialized as part of the dynamic_func_defs. */
 		SERIALIZE_PTR(zend_ast_get_op_array(ast)->op_array);
+	} else if (ast->kind == ZEND_AST_CALLABLE_CONVERT) {
+		zend_ast_fcc *fcc = (zend_ast_fcc*)ast;
+		ZEND_MAP_PTR_INIT(fcc->fptr, NULL);
 	} else if (zend_ast_is_decl(ast)) {
 		/* Not implemented. */
 		ZEND_UNREACHABLE();
@@ -1251,6 +1254,9 @@ static void zend_file_cache_unserialize_ast(zend_ast                *ast,
 	} else if (ast->kind == ZEND_AST_OP_ARRAY) {
 		/* The op_array itself will be unserialized as part of the dynamic_func_defs. */
 		UNSERIALIZE_PTR(zend_ast_get_op_array(ast)->op_array);
+	} else if (ast->kind == ZEND_AST_CALLABLE_CONVERT) {
+		zend_ast_fcc *fcc = (zend_ast_fcc*)ast;
+		ZEND_MAP_PTR_NEW(fcc->fptr);
 	} else if (zend_ast_is_decl(ast)) {
 		/* Not implemented. */
 		ZEND_UNREACHABLE();
diff --git a/ext/opcache/zend_persist.c b/ext/opcache/zend_persist.c
index bf0b3d1988144..df088d1231b75 100644
--- a/ext/opcache/zend_persist.c
+++ b/ext/opcache/zend_persist.c
@@ -195,6 +195,9 @@ static zend_ast *zend_persist_ast(zend_ast *ast)
 		zend_persist_op_array(&z);
 		copy->op_array = Z_PTR(z);
 		node = (zend_ast *) copy;
+	} else if (ast->kind == ZEND_AST_CALLABLE_CONVERT) {
+		zend_ast_fcc *copy = zend_shared_memdup(ast, sizeof(zend_ast_fcc));
+		node = (zend_ast *) copy;
 	} else if (zend_ast_is_decl(ast)) {
 		/* Not implemented. */
 		ZEND_UNREACHABLE();
diff --git a/ext/opcache/zend_persist_calc.c b/ext/opcache/zend_persist_calc.c
index 0c53923354c42..bb4f9c7170f28 100644
--- a/ext/opcache/zend_persist_calc.c
+++ b/ext/opcache/zend_persist_calc.c
@@ -91,6 +91,8 @@ static void zend_persist_ast_calc(zend_ast *ast)
 		zval z;
 		ZVAL_PTR(&z, zend_ast_get_op_array(ast)->op_array);
 		zend_persist_op_array_calc(&z);
+	} else if (ast->kind == ZEND_AST_CALLABLE_CONVERT) {
+		ADD_SIZE(sizeof(zend_ast_fcc));
 	} else if (zend_ast_is_decl(ast)) {
 		/* Not implemented. */
 		ZEND_UNREACHABLE();