bug#21401: 11.88.6; Incorrect detection of TeX variant

[Jonathan Underwood]

The following simple file results in AucTeX assuming the compiler to
run is AmS-TeX which no longer exists on most machines.


\documentclass[11pt]{article}
 \usepackage{basicart1}
\begin{document}

\Document{DocNum}{\today}
\Title{Title of an Article}
{
  \makebox[0.20\textwidth][c]{
     Name of the Author
  }
}
{
  \makebox[0.17\textwidth][c]{%
%    \footnotesize address@hidden
  }
}
{%
  Short Title
}
{%
  Short Author
}
\end{document}



Emacs  : GNU Emacs 24.5.1 (x86_64-redhat-linux-gnu, GTK+ Version 3.16.2)
 of 2015-04-22 on buildhw-10.phx2.fedoraproject.org
Package: 11.88.6

current state:
==============
(setq
 AUCTeX-date "2015-05-08"
 window-system 'x
 LaTeX-version "2e"
 TeX-style-path '("~/.emacs.d/auctex"
          "/home/jgu/.emacs.d/elpa/auctex-11.88.6/style"
          "/home/jgu/.emacs.d/auctex/auto"
          "/home/jgu/.emacs.d/auctex/style" "auto" "style")
 TeX-auto-save t
 TeX-parse-self t
 TeX-master nil
 TeX-command-list '(("TeX"
             "%(PDF)%(tex) %(file-line-error) %(extraopts)
%`%S%(PDFout)%(mode)%' %t"
             TeX-run-TeX nil
             (plain-tex-mode ams-tex-mode texinfo-mode) :help
             "Run plain TeX")
            ("LaTeX" "%`%l%(mode)%' %t" TeX-run-TeX nil
             (latex-mode doctex-mode) :help "Run LaTeX")
            ("Makeinfo" "makeinfo %(extraopts) %t" TeX-run-compile nil
             (texinfo-mode) :help "Run Makeinfo with Info output")
            ("Makeinfo HTML" "makeinfo %(extraopts) --html %t"
             TeX-run-compile nil (texinfo-mode) :help
             "Run Makeinfo with HTML output")
            ("AmSTeX"
             "%(PDF)amstex %(extraopts) %`%S%(PDFout)%(mode)%' %t"
             TeX-run-TeX nil (ams-tex-mode) :help "Run AMSTeX")
            ("ConTeXt"
             "texexec --once --texutil %(extraopts) %(execopts)%t"
             TeX-run-TeX nil (context-mode) :help "Run ConTeXt once")
            ("ConTeXt Full" "texexec %(extraopts) %(execopts)%t"
             TeX-run-TeX nil (context-mode) :help
             "Run ConTeXt until completion")
            ("BibTeX" "bibtex %s" TeX-run-BibTeX nil t :help
             "Run BibTeX")
            ("Biber" "biber %s" TeX-run-Biber nil t :help "Run Biber")
            ("View" "%V" TeX-run-discard-or-function t t :help
             "Run Viewer")
            ("Print" "%p" TeX-run-command t t :help "Print the file")
            ("Queue" "%q" TeX-run-background nil t :help
             "View the printer queue" :visible TeX-queue-command)
            ("File" "%(o?)dvips %d -o %f " TeX-run-command t t :help
             "Generate PostScript file")
            ("Index" "makeindex %s" TeX-run-command nil t :help
             "Create index file")
            ("Xindy" "texindy %s" TeX-run-command nil t :help
             "Run xindy to create index file")
            ("Check" "lacheck %s" TeX-run-compile nil (latex-mode)
             :help "Check LaTeX file for correctness")
            ("ChkTeX" "chktex -v6 %s" TeX-run-compile nil (latex-mode)
             :help "Check LaTeX file for common mistakes")
            ("Spell" "(TeX-ispell-document \"\")" TeX-run-function nil
             t :help "Spell-check the document")
            ("Clean" "TeX-clean" TeX-run-function nil t :help
             "Delete generated intermediate files")
            ("Clean All" "(TeX-clean t)" TeX-run-function nil t :help
             "Delete generated intermediate and output files")
            ("Other" "" TeX-run-command t t :help
             "Run an arbitrary command")
            )
 )