diff --git a/reactos/win32ss/gdi/eng/device.c b/reactos/win32ss/gdi/eng/device.c
index d5b65ccff61..c7e91e4e9ad 100644
--- a/reactos/win32ss/gdi/eng/device.c
+++ b/reactos/win32ss/gdi/eng/device.c
@@ -212,7 +212,7 @@ EngpRegisterGraphicsDevice(
                   pdm->dmBitsPerPel,
                   pdm->dmDisplayFrequency);
             /* Compare with the default entry */
-            if (!bModeMatch && 
+            if (!bModeMatch &&
                 pdm->dmBitsPerPel == pdmDefault->dmBitsPerPel &&
                 pdm->dmPelsWidth == pdmDefault->dmPelsWidth &&
                 pdm->dmPelsHeight == pdmDefault->dmPelsHeight)
@@ -438,13 +438,15 @@ EngFileIoControl(
 /*
  * @implemented
  */
-DWORD APIENTRY
+_Success_(return==0)
+DWORD
+APIENTRY
 EngDeviceIoControl(
     _In_ HANDLE hDevice,
     _In_ DWORD dwIoControlCode,
-    _In_opt_bytecount_(cjInBufferSize) LPVOID lpInBuffer,
+    _In_reads_bytes_opt_(cjInBufferSize) LPVOID lpInBuffer,
     _In_ DWORD cjInBufferSize,
-    _Out_opt_bytecap_(cjOutBufferSize) LPVOID lpOutBuffer,
+    _Out_writes_bytes_opt_(cjOutBufferSize) LPVOID lpOutBuffer,
     _In_ DWORD cjOutBufferSize,
     _Out_ LPDWORD lpBytesReturned)
 {
diff --git a/reactos/win32ss/gdi/ntgdi/gdidebug.h b/reactos/win32ss/gdi/ntgdi/gdidebug.h
index 15302e58340..9d09a698ef7 100644
--- a/reactos/win32ss/gdi/ntgdi/gdidebug.h
+++ b/reactos/win32ss/gdi/ntgdi/gdidebug.h
@@ -11,14 +11,6 @@
 #define KeRosDumpStackFrames(Frames, Count)
 #endif
 
-NTSYSAPI
-ULONG
-APIENTRY
-RtlWalkFrameChain(
-    _Out_ PVOID *Callers,
-    _In_ ULONG Count,
-    _In_ ULONG Flags);
-
 ULONG
 NTAPI
 DbgCaptureStackBackTace(
diff --git a/reactos/win32ss/include/ntuser.h b/reactos/win32ss/include/ntuser.h
index c2b688c59f8..75f5c41a02f 100644
--- a/reactos/win32ss/include/ntuser.h
+++ b/reactos/win32ss/include/ntuser.h
@@ -2982,8 +2982,8 @@ BOOL
 NTAPI
 NtUserSetCursorIconData(
     _In_ HCURSOR hCursor,
-    _In_ PUNICODE_STRING pustrModule,
-    _In_ PUNICODE_STRING puSrcName,
+    _In_opt_ PUNICODE_STRING pustrModule,
+    _In_opt_ PUNICODE_STRING puSrcName,
     _In_ const CURSORDATA *pCursorData);
 
 typedef struct _tagFINDEXISTINGCURICONPARAM
diff --git a/reactos/win32ss/user/ntuser/cursoricon.c b/reactos/win32ss/user/ntuser/cursoricon.c
index f8db31f9272..a525fb75fa3 100644
--- a/reactos/win32ss/user/ntuser/cursoricon.c
+++ b/reactos/win32ss/user/ntuser/cursoricon.c
@@ -395,15 +395,16 @@ IntCleanupCurIconCache(PPROCESSINFO Win32Process)
 /*
  * @implemented
  */
+_Success_(return != FALSE)
 BOOL
-APIENTRY
+NTAPI
 NtUserGetIconInfo(
-  _In_       HANDLE hCurIcon,
-  _Out_opt_  PICONINFO IconInfo,
-  _Out_opt_  PUNICODE_STRING lpModule,   // Optional
-  _Out_opt_  PUNICODE_STRING lpResName,  // Optional
-  _Out_opt_  LPDWORD pbpp,               // Optional
-  _In_       BOOL bInternal)
+    _In_ HANDLE hCurIcon,
+    _Out_opt_ PICONINFO IconInfo,
+    _Inout_opt_ PUNICODE_STRING lpModule,
+    _Inout_opt_ PUNICODE_STRING lpResName,
+    _Out_opt_ LPDWORD pbpp,
+    _In_ BOOL bInternal)
 {
     ICONINFO ii;
     PCURICON_OBJECT CurIcon;
diff --git a/reactos/win32ss/user/ntuser/useratom.c b/reactos/win32ss/user/ntuser/useratom.c
index 46d9832a7ac..b9cbf185f80 100644
--- a/reactos/win32ss/user/ntuser/useratom.c
+++ b/reactos/win32ss/user/ntuser/useratom.c
@@ -91,8 +91,8 @@ IntAddGlobalAtom(LPWSTR lpBuffer, BOOL PinAtom)
  * \note The function does not aquire any global lock, since synchronisation is
  *       handled by the RtlAtom function.
  */
-_Success_(return!=0)
-_At_(pustrName->Buffer, _Out_z_bytecap_post_bytecount_(pustrName->MaximumLength, return*2+2))
+_Success_(return != 0)
+_At_(pustrName->Buffer, _Out_z_bytecap_post_bytecount_(pustrName->MaximumLength, return * 2 + 2))
 ULONG
 APIENTRY
 NtUserGetAtomName(