diff --git a/Makefile-rpm-ostree.am b/Makefile-rpm-ostree.am
index b07008f4..a7a6e5a2 100644
--- a/Makefile-rpm-ostree.am
+++ b/Makefile-rpm-ostree.am
@@ -33,7 +33,7 @@ rpm_ostree_SOURCES = src/app/main.cxx \
 	src/app/rpmostree-builtin-initramfs-etc.c \
 	src/app/rpmostree-builtin-livefs.c \
 	src/app/rpmostree-builtin-usroverlay.c \
-	src/app/rpmostree-builtin-override.c \
+	src/app/rpmostree-builtin-override.cxx \
 	src/app/rpmostree-builtin-refresh-md.c \
 	src/app/rpmostree-builtin-reset.cxx \
 	src/app/rpmostree-pkg-builtins.cxx \
diff --git a/src/app/rpmostree-builtin-override.c b/src/app/rpmostree-builtin-override.cxx
similarity index 97%
rename from src/app/rpmostree-builtin-override.c
rename to src/app/rpmostree-builtin-override.cxx
index fdfe4138..aae53096 100644
--- a/src/app/rpmostree-builtin-override.c
+++ b/src/app/rpmostree-builtin-override.cxx
@@ -33,7 +33,7 @@ static RpmOstreeCommand override_subcommands[] = {
   { "reset", RPM_OSTREE_BUILTIN_FLAG_SUPPORTS_PKG_INSTALLS,
     "Reset currently active package overrides",
     rpmostree_override_builtin_reset },
-  { NULL, 0, NULL, NULL }
+  { NULL, (RpmOstreeBuiltinFlags)0, NULL, NULL }
 };
 
 gboolean