luaotfload-tool --diagnose=permissions fails because it looks for luaotfload-names.luc in uncompressed format

[cfr42]

Ref.: https://tex.stackexchange.com/q/715533/ (but the question describes multiple luaotfload-tool bugs)

luaotfload | diagnose : =============== file permissions ==============
luaotfload | diagnose : Checking permissions of /home/username/.texlive2024/texmf-var/luatex-cache/generic/.
luaotfload | diagnose : Owner: 1000, group 1000, permissions rwxr-xr-x.
luaotfload | diagnose : Readable: ok.
luaotfload | diagnose : Writable: ok.
luaotfload | diagnose : Checking permissions of /home/username/.texlive2024/texmf-var/luatex-cache/generic/names.
luaotfload | diagnose : Owner: 1000, group 1000, permissions rwxr-xr-x.
luaotfload | diagnose : Readable: ok.
luaotfload | diagnose : Writable: ok.
luaotfload | diagnose : Checking permissions of /home/username/.texlive2024/texmf-var/luatex-cache/generic/names/luaotfload-names.lua.gz.
luaotfload | diagnose : Owner: 1000, group 1000, permissions rw-r--r--.
luaotfload | diagnose : Readable: ok.
luaotfload | diagnose : Writable: ok.
luaotfload | diagnose : Checking permissions of /home/username/.texlive2024/texmf-var/luatex-cache/generic/names/luaotfload-names.luc.

attr    /home/username/.texlive2024/texmf-var/luatex-cache/generic/names/luaotfload-names.luc   nil

This fails because the file doesn't exist. luaotfload-names.luc is present, but only in compressed format as luaotfload-names.luc.gz. This is apparently fine when using LuaTeX but not fine with luaotfload-tool.

Comparison/Related

I'm reporting separately from https://github.com/latex3/luaotfload/issues/281 as the cause seems different and, unlike that bug, this one doesn't appear to have existed in 2020. https://github.com/latex3/luaotfload/issues/168 says that 'all other self-tests' --- presumably including the permissions check --- were fine.

Version details

$ luaotfload-tool --version

luaotfload-tool:
Luaotfload font management and diagnostic utility.
License: GNU GPL v2.0.
Report problems to <https://github.com/latex3/luaotfload/issues>

luaotfload-tool version: "3.28"
Revision: nil
Lua interpreter: stock; version "Lua 5.3"
Luatex version: 1.18
Platform: type=unix name=linux
+  machine: x86_64
+ nodename: MyComputer
+  release: 6.8.2-arch2-1
+  sysname: Linux
+  version: #1 SMP PREEMPT_DYNAMIC Thu, 28 Mar 2024 17:06:35 +0000
Index: version=6 created="2024-03-26 19:18:36" modified="2024-04-05 01:10:24"

and

$ tlmgr info luaotfload
package:     luaotfload
category:    Package
shortdesc:   OpenType 'loader' for Plain TeX and LaTeX
longdesc:    The package adopts the TrueType/OpenType Font loader code provided in ConTeXt, and adapts it to use in Plain TeX and LaTeX. It works under LuaLaTeX only.
installed:   Yes
revision:    70232
sizes:       src: 25k, doc: 1105k, run: 7665k, bin: 5k
relocatable: No
cat-version: 3.28
cat-license: gpl2
cat-topics:  font-use luatex
cat-contact-support: https://github.com/latex3/luaotfload/issues
cat-contact-repository: https://github.com/latex3/luaotfload
collection:  collection-luatex

[zauguin]

Resolved in dc1443546691b3229d313a93686a53bf9c7d2893