diff --git a/src/os/locale.zig b/src/os/locale.zig
index 5f0a960bc..8a8e3293d 100644
--- a/src/os/locale.zig
+++ b/src/os/locale.zig
@@ -26,7 +26,7 @@ pub fn ensureLocale() void {
 
     // Set the locale to whatever is set in env vars.
     if (setlocale(LC_ALL, "")) |v| {
-        log.debug("setlocale result={s}", .{v});
+        log.info("setlocale from env result={s}", .{v});
         return;
     }
 
@@ -34,19 +34,30 @@ pub fn ensureLocale() void {
     // invalid. Try to set it without the LANG var set to use the system
     // default.
     if (std.os.getenv("LANG")) |old_lang| {
-        _ = unsetenv("LANG");
-        defer _ = setenv("LANG", old_lang.ptr, 1);
+        if (old_lang.len > 0) {
+            // The old_lang pointer can be invalidated by unsetenv so we need
+            // to make a copy. LANG should never be longer than 128 bytes. If
+            // it is, we just set it to "".
+            var buf: [128]u8 = undefined;
+            var fba = std.heap.FixedBufferAllocator.init(&buf);
+            const alloc = fba.allocator();
+            const old_copy = alloc.dupeZ(u8, old_lang) catch "";
 
-        if (setlocale(LC_ALL, "")) |v| {
-            log.debug("setlocale result={s}", .{v});
-            return;
+            // Unset the lang and defer to reset the copy.
+            _ = unsetenv("LANG");
+            defer _ = setenv("LANG", old_copy.ptr, 1);
+
+            if (setlocale(LC_ALL, "")) |v| {
+                log.info("setlocale after unset lang result={s}", .{v});
+                return;
+            }
         }
     }
 
     // Failure again... fallback to en_US.UTF-8
     log.warn("setlocale failed with LANG and system default. Falling back to en_US.UTF-8", .{});
     if (setlocale(LC_ALL, "en_US.UTF-8")) |v| {
-        log.debug("setlocale result={s}", .{v});
+        log.info("setlocale default result={s}", .{v});
         return;
     } else log.err("setlocale failed even with the fallback, uncertain results", .{});
 }