diff --git a/dlls/user32/user32.spec b/dlls/user32/user32.spec
index cae0beda498..acf386c9bd2 100644
--- a/dlls/user32/user32.spec
+++ b/dlls/user32/user32.spec
@@ -257,8 +257,8 @@
 @ stdcall GetClassInfoW(long wstr ptr)
 @ stdcall GetClassLongA(long long)
 @ stdcall GetClassLongW(long long)
-@ stdcall GetClassLongPtrA(long long)
-@ stdcall GetClassLongPtrW(long long)
+@ stdcall -arch=win64 GetClassLongPtrA(long long)
+@ stdcall -arch=win64 GetClassLongPtrW(long long)
 @ stdcall GetClassNameA(long ptr long)
 @ stdcall GetClassNameW(long ptr long)
 @ stdcall GetClassWord(long long)
@@ -376,8 +376,8 @@
 @ stdcall GetWindowDC(long)
 @ stdcall GetWindowInfo(long ptr)
 @ stdcall GetWindowLongA(long long)
-@ stdcall GetWindowLongPtrA(long long)
-@ stdcall GetWindowLongPtrW(long long)
+@ stdcall -arch=win64 GetWindowLongPtrA(long long)
+@ stdcall -arch=win64 GetWindowLongPtrW(long long)
 @ stdcall GetWindowLongW(long long)
 @ stdcall GetWindowModuleFileName(long ptr long) GetWindowModuleFileNameA
 @ stdcall GetWindowModuleFileNameA(long ptr long)
@@ -604,8 +604,8 @@
 @ stdcall SetCaretBlinkTime(long)
 @ stdcall SetCaretPos(long long)
 @ stdcall SetClassLongA(long long long)
-@ stdcall SetClassLongPtrA(long long long)
-@ stdcall SetClassLongPtrW(long long long)
+@ stdcall -arch=win64 SetClassLongPtrA(long long long)
+@ stdcall -arch=win64 SetClassLongPtrW(long long long)
 @ stdcall SetClassLongW(long long long)
 @ stdcall SetClassWord(long long long)
 @ stdcall SetClipboardData(long long)
@@ -667,8 +667,8 @@
 @ stdcall SetWindowContextHelpId(long long)
 @ stub SetWindowFullScreenState
 @ stdcall SetWindowLongA(long long long)
-@ stdcall SetWindowLongPtrA(long long long)
-@ stdcall SetWindowLongPtrW(long long long)
+@ stdcall -arch=win64 SetWindowLongPtrA(long long long)
+@ stdcall -arch=win64 SetWindowLongPtrW(long long long)
 @ stdcall SetWindowLongW(long long long)
 @ stdcall SetWindowPlacement(long ptr)
 @ stdcall SetWindowPos(long long long long long long long)