diff --git a/NEWS b/NEWS
index 1984a4a81dc52..a9426d9a22b6e 100644
--- a/NEWS
+++ b/NEWS
@@ -5,6 +5,8 @@ PHP                                                                        NEWS
 - Core:
   . Destructing non-array values (other than NULL) using [] or list() now
     emits a warning. (Girgias)
+  . Fixed bug GH-19637 (Incorrect Closure scope for FCC in constant
+    expression). (timwolla)
 
 - Opcache:
   . Fixed bug GH-19486 (Incorrect opline after deoptimization). (Arnaud)
diff --git a/Zend/tests/first_class_callable/constexpr/autoload.phpt b/Zend/tests/first_class_callable/constexpr/autoload.phpt
index 2dd2561f9a369..c962b77f12b61 100644
--- a/Zend/tests/first_class_callable/constexpr/autoload.phpt
+++ b/Zend/tests/first_class_callable/constexpr/autoload.phpt
@@ -26,6 +26,6 @@ var_dump(Closure);
 Autoloading AutoloadedClass
 object(Closure)#%d (1) {
   ["function"]=>
-  string(16) "withStaticMethod"
+  string(33) "AutoloadedClass::withStaticMethod"
 }
 Called AutoloadedClass::withStaticMethod
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
index efffa4a1d366a..54c96c915635d 100644
--- 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
@@ -1,5 +1,5 @@
 --TEST--
-FCC in initializer errors for static reference to instance method.
+FCC in initializer warns for static reference to trait method.
 --FILE--
 <?php
 
@@ -20,7 +20,7 @@ var_dump(Closure);
 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"
+  string(13) "Foo::myMethod"
   ["parameter"]=>
   array(1) {
     ["$foo"]=>
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
index d36f7c97651e0..97831a8d65f0e 100644
--- 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
@@ -1,5 +1,5 @@
 --TEST--
-FCC in initializer errors for static reference to instance method (Exception).
+FCC in initializer emits deprecation for static reference to trait method (Exception).
 --FILE--
 <?php
 
diff --git a/Zend/tests/first_class_callable/constexpr/gh19637_closure_scope.phpt b/Zend/tests/first_class_callable/constexpr/gh19637_closure_scope.phpt
new file mode 100644
index 0000000000000..254bbc47df48c
--- /dev/null
+++ b/Zend/tests/first_class_callable/constexpr/gh19637_closure_scope.phpt
@@ -0,0 +1,108 @@
+--TEST--
+FCC in attribute sets Closure scope.
+--EXTENSIONS--
+reflection
+--FILE--
+<?php
+
+#[Attribute(Attribute::TARGET_CLASS)]
+class Attr {
+    public function __construct(public array $value) {}
+}
+
+class F {
+    public static function foreign() {}
+}
+
+class G extends F { }
+
+#[Attr([
+    F::foreign(...),
+    G::foreign(...),
+    self::myMethod(...),
+    strrev(...),
+])]
+class C {
+    private static function myMethod(string $foo) {
+        return "XXX";
+    }
+
+    public static function foo() {
+        foreach ([
+            F::foreign(...),
+            G::foreign(...),
+            self::myMethod(...),
+            strrev(...),
+        ] as $fn) {
+            $r = new \ReflectionFunction($fn);
+            var_dump($r->getClosureCalledClass());
+            var_dump($r->getClosureScopeClass());
+        }
+    }
+}
+ 
+foreach ((new ReflectionClass(C::class))->getAttributes() as $reflectionAttribute) {
+    foreach ($reflectionAttribute->newInstance()->value as $fn) {
+        $r = new \ReflectionFunction($fn);
+        var_dump($r->getClosureCalledClass());
+        var_dump($r->getClosureScopeClass());
+    }
+}
+echo "=======\n";
+C::foo();
+
+?>
+--EXPECTF--
+object(ReflectionClass)#%d (1) {
+  ["name"]=>
+  string(1) "F"
+}
+object(ReflectionClass)#%d (1) {
+  ["name"]=>
+  string(1) "F"
+}
+object(ReflectionClass)#%d (1) {
+  ["name"]=>
+  string(1) "G"
+}
+object(ReflectionClass)#%d (1) {
+  ["name"]=>
+  string(1) "F"
+}
+object(ReflectionClass)#%d (1) {
+  ["name"]=>
+  string(1) "C"
+}
+object(ReflectionClass)#%d (1) {
+  ["name"]=>
+  string(1) "C"
+}
+NULL
+NULL
+=======
+object(ReflectionClass)#%d (1) {
+  ["name"]=>
+  string(1) "F"
+}
+object(ReflectionClass)#%d (1) {
+  ["name"]=>
+  string(1) "F"
+}
+object(ReflectionClass)#%d (1) {
+  ["name"]=>
+  string(1) "G"
+}
+object(ReflectionClass)#%d (1) {
+  ["name"]=>
+  string(1) "F"
+}
+object(ReflectionClass)#%d (1) {
+  ["name"]=>
+  string(1) "C"
+}
+object(ReflectionClass)#%d (1) {
+  ["name"]=>
+  string(1) "C"
+}
+NULL
+NULL
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
index 3959efbd16a05..1776cd8f319de 100644
--- a/Zend/tests/first_class_callable/constexpr/property_initializer_scope_003.phpt
+++ b/Zend/tests/first_class_callable/constexpr/property_initializer_scope_003.phpt
@@ -23,7 +23,7 @@ var_dump(($c->d)("abc"));
 --EXPECTF--
 object(Closure)#%d (2) {
   ["function"]=>
-  string(11) "C::myMethod"
+  string(11) "P::myMethod"
   ["parameter"]=>
   array(1) {
     ["$foo"]=>
diff --git a/Zend/tests/first_class_callable/constexpr/static_call.phpt b/Zend/tests/first_class_callable/constexpr/static_call.phpt
index 26761a041a4cc..2c6d3aa92b52f 100644
--- a/Zend/tests/first_class_callable/constexpr/static_call.phpt
+++ b/Zend/tests/first_class_callable/constexpr/static_call.phpt
@@ -19,7 +19,7 @@ var_dump(Closure);
 --EXPECTF--
 object(Closure)#%d (2) {
   ["function"]=>
-  string(8) "myMethod"
+  string(13) "Foo::myMethod"
   ["parameter"]=>
   array(1) {
     ["$foo"]=>
diff --git a/Zend/zend_ast.c b/Zend/zend_ast.c
index 2f66d8d5cd2b1..9cb3c7aae4a1f 100644
--- a/Zend/zend_ast.c
+++ b/Zend/zend_ast.c
@@ -1055,6 +1055,7 @@ ZEND_API zend_result ZEND_FASTCALL zend_ast_evaluate_inner(
 		case ZEND_AST_STATIC_CALL:
 		{
 			zend_function *fptr;
+			zend_class_entry *called_scope = NULL;
 			switch (ast->kind) {
 				case ZEND_AST_CALL: {
 					ZEND_ASSERT(ast->child[1]->kind == ZEND_AST_CALLABLE_CONVERT);
@@ -1086,13 +1087,15 @@ ZEND_API zend_result ZEND_FASTCALL zend_ast_evaluate_inner(
 					ZEND_ASSERT(ast->child[2]->kind == ZEND_AST_CALLABLE_CONVERT);
 					zend_ast_fcc *fcc_ast = (zend_ast_fcc*)ast->child[2];
 
+					zend_class_entry *ce = zend_ast_fetch_class(ast->child[0], scope);
+					if (!ce) {
+						return FAILURE;
+					}
+					called_scope = ce;
+
 					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);
@@ -1145,7 +1148,7 @@ ZEND_API zend_result ZEND_FASTCALL zend_ast_evaluate_inner(
 				}
 			}
 
-			zend_create_fake_closure(result, fptr, scope, scope, NULL);
+			zend_create_fake_closure(result, fptr, fptr->common.scope, called_scope, NULL);
 
 			return SUCCESS;
 		}