diff --git a/reactos/include/psdk/winbase.h b/reactos/include/psdk/winbase.h
index cfc130ee007..dcb8751a3e3 100644
--- a/reactos/include/psdk/winbase.h
+++ b/reactos/include/psdk/winbase.h
@@ -1,8 +1,5 @@
 #ifndef _WINBASE_
 #define _WINBASE_
-#if __GNUC__ >= 3
-#pragma GCC system_header
-#endif
 
 #if !defined(_KERNEL32_)
 #define WINBASEAPI DECLSPEC_IMPORT
diff --git a/reactos/include/psdk/wingdi.h b/reactos/include/psdk/wingdi.h
index 71311d117fc..40e2d63fd31 100644
--- a/reactos/include/psdk/wingdi.h
+++ b/reactos/include/psdk/wingdi.h
@@ -1,9 +1,6 @@
 #ifndef _WINGDI_H
 #define _WINGDI_H
 #define _WINGDI_
-#if __GNUC__ >= 3
-#pragma GCC system_header
-#endif
 
 #ifdef __cplusplus
 extern "C" {
diff --git a/reactos/include/psdk/winuser.h b/reactos/include/psdk/winuser.h
index 2682662525f..68cc43faee1 100644
--- a/reactos/include/psdk/winuser.h
+++ b/reactos/include/psdk/winuser.h
@@ -1,8 +1,5 @@
 #ifndef _WINUSER_H
 #define _WINUSER_H
-#if __GNUC__ >= 3
-#pragma GCC system_header
-#endif
 
 #ifdef __cplusplus
 extern "C" {
diff --git a/reactos/include/reactos/wine/winuser.h b/reactos/include/reactos/wine/winuser.h
index 9d11b5cb047..36c14d68d93 100644
--- a/reactos/include/reactos/wine/winuser.h
+++ b/reactos/include/reactos/wine/winuser.h
@@ -19,8 +19,6 @@
 WINUSERAPI UINT WINAPI PrivateExtractIconsA(LPCSTR,int,int,int,HICON*,UINT*,UINT,UINT);
 WINUSERAPI UINT WINAPI PrivateExtractIconsW(LPCWSTR,int,int,int,HICON*,UINT*,UINT,UINT);
 
-typedef struct tagCWPSTRUCT *LPCWPSTRUCT;
-
 #define WM_ALTTABACTIVE         0x0029
 
 #define UNICODE_NOCHAR          0xFFFF