diff --git a/src/builtin.cpp b/src/builtin.cpp
index f7103a0bf..802f95bc5 100644
--- a/src/builtin.cpp
+++ b/src/builtin.cpp
@@ -546,7 +546,7 @@ void builtin_get_names(std::vector<completion_t> *list) {
 
 /// Return a one-line description of the specified builtin.
 const wchar_t *builtin_get_desc(const wcstring &name) {
-    const wchar_t *result;
+    const wchar_t *result = L"";
     const builtin_data_t *builtin = builtin_lookup(name);
     if (builtin) {
         result = _(builtin->desc);