This simple MWE:
% arara: pdflatex
\documentclass[final]{ltugboat}
\usepackage{hyperref}
\begin{document}
prova
\end{document}
gives this error:
! Undefined control sequence.
l.4767 \ifdim\number\XeTeXversion
\XeTeXrevision in<0.9995in %
?
! Emergency stop.
l.4767 \ifdim\number\XeTeXversion
\XeTeXrevision in<0.9995in %
End of file on the terminal!
It worked since some time ago.
Is it a bug?
It was a bug.
After waiting for fixing and updating my TeX distribution, now it works.
The versions of the packages now used are:
*File List*
ltugboat.cls 2019-11-09 v2.22 TUGboat journal class
article.cls 2019/10/25 v1.4k Standard LaTeX document class
size10.clo 2019/10/25 v1.4k Standard LaTeX file (size option)
mflogo.sty 1999/03/10 v2.0 LaTeX package for Metafont and MetaPost logos
hyperref.sty 2019/11/10 v7.00c Hypertext links for LaTeX
ltxcmds.sty 2016/05/16 v1.23 LaTeX kernel commands for general use (HO)
iftex.sty 2019/11/07 v1.0c TeX engine tests
pdftexcmds.sty 2019/07/25 v0.30 Utility functions of pdfTeX for LuaTeX (HO)
infwarerr.sty 2016/05/16 v1.4 Providing info/warning/error messages (HO)
ifluatex.sty 2019/10/25 v1.5 ifluatex legacy package. Use iftex instead.
ifpdf.sty 2019/10/25 v3.4 ifpdf legacy package. Use iftex instead.
keyval.sty 2014/10/28 v1.15 key=value parser (DPC)
kvsetkeys.sty 2016/05/16 v1.17 Key value parser (HO)
etexcmds.sty 2016/05/16 v1.6 Avoid name clashes with e-TeX commands (HO)
kvdefinekeys.sty 2016/05/16 v1.4 Define keys (HO)
pdfescape.sty 2016/05/16 v1.14 Implements pdfTeX's escape features (HO)
hycolor.sty 2016/05/16 v1.8 Color options for hyperref/bookmark (HO)
xcolor-patch.sty 2016/05/16 xcolor patch
hopatch.sty 2016/05/16 v1.3 Wrapper for package hooks (HO)
letltxmacro.sty 2016/05/16 v1.5 Let assignment for LaTeX macros (HO)
auxhook.sty 2016/05/16 v1.4 Hooks for auxiliary files (HO)
kvoptions.sty 2016/05/16 v3.12 Key value format for package options (HO)
pd1enc.def 2019/11/10 v7.00c Hyperref: PDFDocEncoding definition (HO)
intcalc.sty 2016/05/16 v1.2 Expandable calculations with integers (HO)
hyperref.cfg 2002/06/06 v1.2 hyperref configuration of TeXLive
url.sty 2013/09/16 ver 3.4 Verb mode for urls, etc.
bitset.sty 2016/05/16 v1.2 Handle bit-vector datatype (HO)
bigintcalc.sty 2016/05/16 v1.4 Expandable calculations on big integers (HO)
atbegshi.sty 2016/06/09 v1.18 At begin shipout hook (HO)
hpdftex.def 2019/11/10 v7.00c Hyperref driver for pdfTeX
atveryend.sty 2016/05/16 v1.9 Hooks at the very end of document (HO)
rerunfilecheck.sty 2016/05/16 v1.8 Rerun checks for auxiliary files (HO)
uniquecounter.sty 2016/05/16 v1.3 Provide unlimited unique counter (HO)
nameref.sty 2019/09/16 v2.46 Cross-referencing by name of section
refcount.sty 2016/05/16 v3.5 Data extraction from label references (HO)
gettitlestring.sty 2016/05/16 v1.5 Cleanup title references (HO)
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