MdeModulePkg/VarCheckHiiLib: clean up VarCheckHiiLibReceiveHiiBinHandler

Building VarCheckHiiLib fails on my clang 19.1.6 setup with the error
 variable 'Status' is used uninitialized whenever 'if' condition is false
due to the DispatchHandle != NULL test.

Calling this function with a NULL handle makes no sense, so move the test
to the function entry and return failure if appropriate.

Signed-off-by: Leif Lindholm <[email protected]>

Author: leiflindholm

MdeModulePkg/Library/VarCheckHiiLib/VarCheckHiiLibStandaloneMm.c

@@ -57,7 +57,7 @@ VarCheckHiiLibReceiveHiiBinHandler (
   //
   // If input is invalid, stop processing this SMI
   //
-  if ((CommBuffer == NULL) || (CommBufferSize == NULL)) {
+  if ((DispatchHandle == NULL) || (CommBuffer == NULL) || (CommBufferSize == NULL)) {
     return EFI_INVALID_PARAMETER;
   }
 
@@ -75,16 +75,16 @@ VarCheckHiiLibReceiveHiiBinHandler (
   }
 
   CopyMem (mMmReceivedVarCheckHiiBin, CommBuffer, mMmReceivedVarCheckHiiBinSize);
-  if (DispatchHandle != NULL) {
-    Status = gMmst->MmiHandlerUnRegister (DispatchHandle);
-  }
+
+  Status = gMmst->MmiHandlerUnRegister (DispatchHandle);
 
   if (EFI_ERROR (Status)) {
     DEBUG ((DEBUG_ERROR, "%a: Failed to unregister handler - %r!\n", __func__, Status));
-  } else {
-    DEBUG ((DEBUG_INFO, "%a: Handler unregistered successfully.\n", __func__));
+    return Status;
   }
 
+  DEBUG ((DEBUG_INFO, "%a: Handler unregistered successfully.\n", __func__));
+
   return EFI_SUCCESS;
 }