diff --git a/rostests/apitests/w32knapi/ntdd/NtGdiDdCreateDirectDrawObject.c b/rostests/apitests/w32knapi/ntdd/NtGdiDdCreateDirectDrawObject.c
index 7f1073a627a..6a0be8f626c 100644
--- a/rostests/apitests/w32knapi/ntdd/NtGdiDdCreateDirectDrawObject.c
+++ b/rostests/apitests/w32knapi/ntdd/NtGdiDdCreateDirectDrawObject.c
@@ -13,7 +13,7 @@ Test_NtGdiDdCreateDirectDrawObject(PTESTINFO pti)
 
 	/* Cleanup ReactX setup */
 	DeleteDC(hdc);
-	Syscall(L"NtGdiDdDeleteDirectDrawObject", 1, &hDirectDraw);
+	NtGdiDdDeleteDirectDrawObject(hDirectDraw);
 
 	return APISTATUS_NORMAL;
 }
diff --git a/rostests/apitests/w32knapi/ntgdi/NtGdiEngCreatePalette.c b/rostests/apitests/w32knapi/ntgdi/NtGdiEngCreatePalette.c
index 386547f3004..015367f8d80 100644
--- a/rostests/apitests/w32knapi/ntgdi/NtGdiEngCreatePalette.c
+++ b/rostests/apitests/w32knapi/ntgdi/NtGdiEngCreatePalette.c
@@ -25,7 +25,7 @@ Test_NtGdiEngCreatePalette(PTESTINFO pti)
 	TEST(GDI_HANDLE_GET_TYPE(hPal) == GDI_OBJECT_TYPE_PALETTE);
 	pEntry = &GdiHandleTable[GDI_HANDLE_GET_INDEX(hPal)];
 	TEST(pEntry->KernelData != NULL);
-	TEST(pEntry->ProcessId == (HANDLE)GetCurrentProcessId());
+	TEST(pEntry->ProcessId == GetCurrentProcessId());
 	TEST(pEntry->UserData == 0);
 	TEST(pEntry->Type == (((UINT)hPal >> 16) | GDI_OBJECT_TYPE_PALETTE));
 
diff --git a/rostests/apitests/w32knapi/ntgdi/NtGdiEnumFontOpen.c b/rostests/apitests/w32knapi/ntgdi/NtGdiEnumFontOpen.c
index 7f30ecdde2b..659d293a787 100644
--- a/rostests/apitests/w32knapi/ntgdi/NtGdiEnumFontOpen.c
+++ b/rostests/apitests/w32knapi/ntgdi/NtGdiEnumFontOpen.c
@@ -1,3 +1,4 @@
+
 INT
 Test_NtGdiEnumFontOpen(PTESTINFO pti)
 {
@@ -17,7 +18,7 @@ Test_NtGdiEnumFontOpen(PTESTINFO pti)
 	TEST(GDI_HANDLE_GET_TYPE(idEnum) == GDI_OBJECT_TYPE_ENUMFONT);
 	pEntry = &GdiHandleTable[GDI_HANDLE_GET_INDEX(idEnum)];
 	TEST(pEntry->KernelData != NULL);
-	TEST(pEntry->ProcessId == (HANDLE)GetCurrentProcessId());
+	TEST(pEntry->ProcessId == GetCurrentProcessId());
 	TEST(pEntry->UserData == 0);
 	TEST(pEntry->Type == ((idEnum >> 16) | GDI_OBJECT_TYPE_ENUMFONT));
 
diff --git a/rostests/apitests/w32knapi/w32knapi.h b/rostests/apitests/w32knapi/w32knapi.h
index a210b4e8c81..2404b3d0312 100644
--- a/rostests/apitests/w32knapi/w32knapi.h
+++ b/rostests/apitests/w32knapi/w32knapi.h
@@ -22,10 +22,6 @@
 
 #include "../apitest.h"
 
-#define OS_UNSUPPORTED 0
-#define OS_REACTOS	1
-#define OS_WINDOWS	2
-
 typedef struct
 {
 	LPWSTR lpszFunction;