diff --git a/src/wildcard.cpp b/src/wildcard.cpp
index a72588edb..899f95ab9 100644
--- a/src/wildcard.cpp
+++ b/src/wildcard.cpp
@@ -736,16 +736,16 @@ void wildcard_expander_t::expand_intermediate_segment(const wcstring &base_dir,
                                                       const wcstring &wc_segment,
                                                       const wchar_t *wc_remainder,
                                                       const wcstring &prefix) {
-    wcstring name_str;
+    std::string narrow;
     int dir_fd = dirfd(base_dir_fp);
-    while (!interrupted_or_overflowed() && wreaddir_for_dirs(base_dir_fp, &name_str)) {
+    while (!interrupted_or_overflowed() && readdir_for_dirs(base_dir_fp, &narrow)) {
+        wcstring name_str = str2wcstring(narrow);
         // Note that it's critical we ignore leading dots here, else we may descend into . and ..
         if (!wildcard_match(name_str, wc_segment, true)) {
             // Doesn't match the wildcard for this segment, skip it.
             continue;
         }
 
-        std::string narrow = wcs2string(name_str);
         struct stat buf;
         if (0 != fstatat(dir_fd, narrow.c_str(), &buf, 0) || !S_ISDIR(buf.st_mode)) {
             // We either can't stat it, or we did but it's not a directory.
@@ -776,18 +776,19 @@ void wildcard_expander_t::expand_literal_intermediate_segment_with_fuzz(const wc
                                                                         const wchar_t *wc_remainder,
                                                                         const wcstring &prefix) {
     // This only works with tab completions. Ordinary wildcard expansion should never go fuzzy.
-    wcstring name_str;
+    std::string narrow;
 
     // Mark that we are fuzzy for the duration of this function
     const scoped_push<bool> scoped_fuzzy(&this->has_fuzzy_ancestor, true);
 
     int dir_fd = dirfd(base_dir_fp);
-    while (!interrupted_or_overflowed() && wreaddir_for_dirs(base_dir_fp, &name_str)) {
+    while (!interrupted_or_overflowed() && readdir_for_dirs(base_dir_fp, &narrow)) {
         // Don't bother with . and ..
-        if (name_str == L"." || name_str == L"..") {
+        if (narrow == "." || narrow == "..") {
             continue;
         }
 
+        wcstring name_str = str2wcstring(narrow);
         // Skip cases that don't match or match exactly. The match-exactly case was handled directly
         // in expand().
         const maybe_t<string_fuzzy_match_t> match = string_fuzzy_match_string(wc_segment, name_str);
diff --git a/src/wutil.cpp b/src/wutil.cpp
index dc11469d5..55c8affef 100644
--- a/src/wutil.cpp
+++ b/src/wutil.cpp
@@ -94,7 +94,7 @@ bool wreaddir(DIR *dir, wcstring &out_name) {
     return true;
 }
 
-bool wreaddir_for_dirs(DIR *dir, wcstring *out_name) {
+bool readdir_for_dirs(DIR *dir, std::string *out_name) {
     struct dirent *result = nullptr;
     while (!result) {
         result = readdir(dir);
@@ -118,7 +118,7 @@ bool wreaddir_for_dirs(DIR *dir, wcstring *out_name) {
     }
 
     if (result && out_name) {
-        *out_name = str2wcstring(result->d_name);
+        *out_name = result->d_name;
     }
     return result != nullptr;
 }
diff --git a/src/wutil.h b/src/wutil.h
index 07be9b8ef..139f5c8aa 100644
--- a/src/wutil.h
+++ b/src/wutil.h
@@ -71,7 +71,7 @@ bool wreaddir_resolving(DIR *dir, const std::wstring &dir_path, wcstring &out_na
 /// (i.e. the file is a symlink), then return it. Note that this does not guarantee that everything
 /// returned is a directory, it's just an optimization for cases where we would check for
 /// directories anyways.
-bool wreaddir_for_dirs(DIR *dir, wcstring *out_name);
+bool readdir_for_dirs(DIR *dir, std::string *out_name);
 
 /// Wide character version of dirname().
 std::wstring wdirname(std::wstring path);