diff --git a/reactos/tools/rbuild/backend/mingw/mingw.cpp b/reactos/tools/rbuild/backend/mingw/mingw.cpp
index 5c178dd4f40..017862e2ea3 100644
--- a/reactos/tools/rbuild/backend/mingw/mingw.cpp
+++ b/reactos/tools/rbuild/backend/mingw/mingw.cpp
@@ -1241,7 +1241,7 @@ MingwBackend::OutputRegistryInstallTarget ()
 	fprintf ( fMakefile,
 	          "\t$(ECHO_MKHIVE)\n" );
 	fprintf ( fMakefile,
-	          "\t$(MKHIVE_TARGET) boot%cbootdata %s $(ROS_ARCH) boot%cbootdata%chiveinst_$(ROS_ARCH).inf\n",
+	          "\t$(MKHIVE_TARGET) boot%cbootdata %s $(ARCH) boot%cbootdata%chiveinst_$(ARCH).inf\n",
 	          cSep, GetFullPath ( system32 ).c_str (),
 	          cSep, cSep );
 	fprintf ( fMakefile,
diff --git a/reactos/tools/rbuild/backend/mingw/modulehandler.cpp b/reactos/tools/rbuild/backend/mingw/modulehandler.cpp
index 77766f06b04..67ad25e3f00 100644
--- a/reactos/tools/rbuild/backend/mingw/modulehandler.cpp
+++ b/reactos/tools/rbuild/backend/mingw/modulehandler.cpp
@@ -3571,7 +3571,7 @@ MingwLiveIsoModuleHandler::OutputRegistryCommands ( string& livecdDirectory )
 	fprintf ( fMakefile,
 	          "\t$(ECHO_MKHIVE)\n" );
 	fprintf ( fMakefile,
-	          "\t$(MKHIVE_TARGET) boot%cbootdata %s $(ROS_ARCH) boot%cbootdata%clivecd.inf boot%cbootdata%chiveinst_$(ROS_ARCH).inf\n",
+	          "\t$(MKHIVE_TARGET) boot%cbootdata %s $(ARCH) boot%cbootdata%clivecd.inf boot%cbootdata%chiveinst_$(ARCH).inf\n",
 	          cSep, backend->GetFullPath ( reactosSystem32ConfigDirectory ).c_str (),
 	          cSep, cSep, cSep, cSep );
 }