我今天更新了 TeX Live。更新的软件包之一是 l3kernel。现在我使用一个昨天运行正常的文件时出现此错误
Package: expl3 2020-06-18 L3 programming layer (loader)
c:/texlive/2020/texmf-dist/tex/latex/l3kernel/expl3.sty:67: Undefined control sequence.
l.67 \bool
_new:N \g__expl_reload_bool
The control sequence at the end of the top lineof your error message was never \def'ed.
例如，
\documentclass{article}
\usepackage{fontspec}
\begin{document}
Hi!
\end{document}
我犯了同样的错误。
任何有关调试此问题的帮助都将不胜感激。
这是出现错误消息之前的日志文件：
This is LuaHBTeX, Version 1.12.0 (TeX Live 2020/W32TeX) (format=lualatex 2020.3.5) 19 JUN 2020 18:41
restricted system commands enabled.
file:line:error style messages enabled.
**example.tex
(./example.tex
LaTeX2e <2020-02-02> patch level 5
Lua module: luaotfload-main 2020-05-06 3.14 luaotfload entry point
Lua module: luaotfload-init 2020-05-06 3.14 luaotfload submodule / initializatio
n
Lua module: lualibs 2020-05-01 2.71 ConTeXt Lua standard libraries.
Lua module: lualibs-extended 2020-05-01 2.71 ConTeXt Lua libraries -- extended c
ollection.
Lua module: luaotfload-log 2020-05-06 3.14 luaotfload submodule / logging
Lua module: luaotfload-parsers 2020-05-06 3.14 luaotfload submodule / filelist
Lua module: luaotfload-configuration 2020-05-06 3.14 luaotfload submodule / conf
ig file reader
luaotfload | conf : Root cache directory is "C:/texlive/2020/texmf-var/luatex-ca
che/generic-dev/names".
luaotfload | init : Loading fontloader "fontloader-2020-05-06.lua" from kpse-res
olved path "c:/texlive/2020/texmf-dist/tex/luatex/luaotfload/fontloader-2020-05-
06.lua".
Lua-only attribute luaotfload@noligature = 2
Lua-only attribute luaotfload@syllabe = 3
luaotfload | init : Context OpenType loader version 0x1.8e353f7ced917p+1
Lua module: luaotfload-fallback 2020-05-06 3.14 luaotfload submodule / fallback
Lua module: luaotfload-multiscript 2020-05-06 3.14 luaotfload submodule / multis
cript
Lua module: luaotfload-script 2020-05-06 3.14 luaotfload submodule / Script help
ers
Inserting `luaotfload.node_processor' at position 1 in `pre_linebreak_filter'.
Inserting `luaotfload.node_processor' at position 1 in `hpack_filter'.
Lua module: luaotfload-loaders 2020-05-06 3.14 luaotfload submodule / callback h
andling
Inserting `luaotfload.define_font' at position 1 in `define_font'.
Lua module: luaotfload-database 2020-05-06 3.14 luaotfload submodule / database
Lua module: luaotfload-unicode 2020-05-06 3.14 luaotfload submodule / Unicode he
lpers
Lua module: luaotfload-colors 2020-05-06 3.14 luaotfload submodule / color
Lua-only attribute luaotfload_color_attribute = 4
Lua module: luaotfload-resolvers 2020-05-06 3.14 luaotfload submodule / resolver
s
luaotfload | conf : Root cache directory is "C:/texlive/2020/texmf-var/luatex-ca
che/generic-dev/names".
Lua module: luaotfload-features 2020-05-06 3.14 luaotfload submodule / features
Lua module: luaotfload-harf-define 2020-05-06 3.14 luaotfload submodule / databa
se
Inserting `luaotfload.harf.strip_prefix' at position 1 in `find_opentype_file'.
Inserting `luaotfload.harf.strip_prefix' at position 1 in `find_truetype_file'.
Lua module: luaotfload-harf-plug 2020-05-06 3.14 luaotfload submodule / database
Inserting `Harf pre_output_filter callback' at position 1 in `pre_output_filter'
.
Inserting `Harf wrapup_run callback' at position 1 in `wrapup_run'.
Inserting `Harf finish_pdffile callback' at position 1 in `finish_pdffile'.
Inserting `Harf glyph_info callback' at position 1 in `glyph_info'.
Lua module: luaotfload-letterspace 2020-05-06 3.14 luaotfload submodule / color
Lua module: luaotfload-embolden 2020-05-06 3.14 luaotfload submodule / color
Lua module: luaotfload-notdef 2020-05-06 3.14 luaotfload submodule / color
Lua module: luaotfload-suppress 2020-05-06 3.14 luaotfload submodule / suppress
Lua module: luaotfload-szss 2020-05-06 3.14 luaotfload submodule / color
Lua module: luaotfload-auxiliary 2020-05-06 3.14 luaotfload submodule / auxiliar
y functions
Inserting `luaotfload.aux.set_sscale_dimens' at position 1 in `luaotfload.patch_
font'.
Inserting `luaotfload.aux.set_font_index' at position 2 in `luaotfload.patch_fon
t'.
Inserting `luaotfload.aux.patch_cambria_domh' at position 3 in `luaotfload.patch
_font'.
Inserting `luaotfload.aux.fixup_fontdata' at position 1 in `luaotfload.patch_fon
t_unsafe'.
Inserting `luaotfload.aux.set_capheight' at position 4 in `luaotfload.patch_font
'.
Inserting `luaotfload.aux.set_xheight' at position 5 in `luaotfload.patch_font'.
Lua module: luaotfload-tounicode 2020-05-06 3.14 luaotfload submodule / tounicod
e
Inserting `luaotfload.rewrite_fontname' at position 6 in `luaotfload.patch_font'
. L3 programming layer <2020-02-25>
(c:/texlive/2020/texmf-dist/tex/latex/base/article.cls
Document Class: article 2019/12/20 v1.4l Standard LaTeX document class
(c:/texlive/2020/texmf-dist/tex/latex/base/size10.clo
File: size10.clo 2019/12/20 v1.4l Standard LaTeX file (size option)
luaotfload | db : Font names database loaded from C:/texlive/2020/texmf-var/luat
ex-cache/generic-dev/names/luaotfload-names.lua.gz)
\c@part=\count163
\c@section=\count164
\c@subsection=\count165
\c@subsubsection=\count166
\c@paragraph=\count167
\c@subparagraph=\count168
\c@figure=\count169
\c@table=\count170
\abovecaptionskip=\skip47
\belowcaptionskip=\skip48
\bibindent=\dimen134
)
(c:/texlive/2020/texmf-dist/tex/latex/fontspec/fontspec.sty
(c:/texlive/2020/texmf-dist/tex/latex/l3packages/xparse/xparse.sty
(c:/texlive/2020/texmf-dist/tex/latex/l3kernel/expl3.sty
Package: expl3 2020-06-18 L3 programming layer (loader)
c:/texlive/2020/texmf-dist/tex/latex/l3kernel/expl3.sty:67: Undefined control se
quence.
l.67 \bool
_new:N \g__expl_reload_bool
The control sequence at the end of the top line
of your error message was never \def'ed. If you have
misspelled it (e.g., `\hobx'), type `I' and the correct
spelling (e.g., `I\hbox'). Otherwise just continue,
and I'll forget about whatever was undefined.