1 files changed, 14 insertions, 0 deletions

diff --git a/src/WixToolset.BootstrapperCore.Native/inc/BundleExtensionEngine.h b/src/WixToolset.BootstrapperCore.Native/inc/BundleExtensionEngine.h
index adcae1af..becb5be3 100644
--- a/src/WixToolset.BootstrapperCore.Native/inc/BundleExtensionEngine.h
+++ b/src/WixToolset.BootstrapperCore.Native/inc/BundleExtensionEngine.h
@@ -27,8 +27,22 @@ enum BUNDLE_EXTENSION_ENGINE_MESSAGE
     BUNDLE_EXTENSION_ENGINE_MESSAGE_SETVARIABLENUMERIC,
     BUNDLE_EXTENSION_ENGINE_MESSAGE_SETVARIABLESTRING,
     BUNDLE_EXTENSION_ENGINE_MESSAGE_SETVARIABLEVERSION,
+    BUNDLE_EXTENSION_ENGINE_MESSAGE_COMPAREVERSIONS,
 };
 
+typedef struct _BUNDLE_EXTENSION_ENGINE_COMPAREVERSIONS_ARGS
+{
+    DWORD cbSize;
+    LPCWSTR wzVersion1;
+    LPCWSTR wzVersion2;
+} BUNDLE_EXTENSION_ENGINE_COMPAREVERSIONS_ARGS;
+
+typedef struct _BUNDLE_EXTENSION_ENGINE_COMPAREVERSIONS_RESULTS
+{
+    DWORD cbSize;
+    int nResult;
+} BUNDLE_EXTENSION_ENGINE_COMPAREVERSIONS_RESULTS;
+
 typedef struct _BUNDLE_EXTENSION_ENGINE_ESCAPESTRING_ARGS
 {
     DWORD cbSize;