diff --git a/dlls/rpcrt4/ndr_marshall.c b/dlls/rpcrt4/ndr_marshall.c
index dbf40746b41..70e78795f21 100644
--- a/dlls/rpcrt4/ndr_marshall.c
+++ b/dlls/rpcrt4/ndr_marshall.c
@@ -132,8 +132,6 @@ static inline void align_pointer_offset_clear( unsigned char **ptr, unsigned cha
 #define NDR_TABLE_SIZE 128
 #define NDR_TABLE_MASK 127
 
-#define NDRSContextFromValue(user_context) (NDR_SCONTEXT)((char *)(user_context) - (char *)NDRSContextValue((NDR_SCONTEXT)NULL))
-
 static unsigned char *WINAPI NdrBaseTypeMarshall(PMIDL_STUB_MESSAGE, unsigned char *, PFORMAT_STRING);
 static unsigned char *WINAPI NdrBaseTypeUnmarshall(PMIDL_STUB_MESSAGE, unsigned char **, PFORMAT_STRING, unsigned char);
 static void WINAPI NdrBaseTypeBufferSize(PMIDL_STUB_MESSAGE, unsigned char *, PFORMAT_STRING);
@@ -7002,7 +7000,7 @@ static unsigned char *WINAPI NdrContextHandleMarshall(
     }
     else
     {
-        NDR_SCONTEXT ctxt = NDRSContextFromValue(pMemory);
+        NDR_SCONTEXT ctxt = CONTAINING_RECORD(pMemory, struct _NDR_SCONTEXT, userContext);
         NDR_RUNDOWN rundown = pStubMsg->StubDesc->apfnNdrRundownRoutines[pFormat[2]];
         NdrServerContextNewMarshall(pStubMsg, ctxt, rundown, pFormat);
     }