1 files changed, 2 insertions, 2 deletions

diff --git a/src/libs/dutil/WixToolset.DUtil/inc/strutil.h b/src/libs/dutil/WixToolset.DUtil/inc/strutil.h
index f2324a80..6710f599 100644
--- a/src/libs/dutil/WixToolset.DUtil/inc/strutil.h
+++ b/src/libs/dutil/WixToolset.DUtil/inc/strutil.h
@@ -309,10 +309,10 @@ HRESULT DAPI StrSplitAllocArray(
     );
 
 HRESULT DAPI StrSecureZeroString(
-    __in LPWSTR pwz
+    __in_z_opt LPWSTR pwz
     );
 HRESULT DAPI StrSecureZeroFreeString(
-    __in LPWSTR pwz
+    __in_z_opt LPWSTR pwz
     );
 
 #ifdef __cplusplus