v 99.1 (release) with input:
\documentclass{article}
\usepackage{amsmath}
\begin{document}
\author{Hi}
\end{document}
goes into an infinite recursion (do_cmd_author -> translate_commands
-> process_command -> do_cmd_author) while "parsing
preamble". Everything is
ok without
\uspackage{amsmath}
Olaf