Red Hat Bugzilla – Bug 152464
Latex freezes
Last modified: 2013-07-02 19:06:18 EDT
Not really severe, but quite unpleasant when you dont know why it freezes. When using LaTeX, having done (by mistake) a recursive new command, latex doesnt detect it, and tries to finish the job anyway, which causes it to freeze. Example : \documentclass{article} \newcommand\vect{\vect} \begin{document} \end{document} I know, I should have done the following, but that's a bug anyway : \documentclass{article} \newcommand\vect{\overrightarrow} \begin{document} \end{document}
PE, this looks like a feature request to the original LaTeX maintainers than a bug that needs to fixed for FC3 teTeX. Could you please report this problem upstream? Read first: http://www.latex-project.org/bugs.html and then please file the bug in: http://www.latex-project.org/bugs-upload.html Could you then add here a reference to the bug you reported so that I can track it? Thanks, Jindrich
I reported it upstream myself. It has the internal identification `latex/3776'.
Upstream developer responded: This is also known as the halting problem. The TeX engine -- and therefore also LaTeX -- is Turing complete and it is a proven fact that a Turing Machine cannot determine in advance that something will cause an infinite loop. It can only be done by executing it and hoping for the best. The good thing about computers being so fast these days is that when you observe LaTeX hanging for a few seconds there is a good chance it's because you accidentally caused it to go into an infinite loop. There are many ways to get LaTeX into an infinite loop and the indispensable The LaTeX Companion 2nd edition has several examples on that topic.