latex compile error level

Question

Thinking of classical programming languages, many compilers support error levels. Error levels let one specify the severity at which the compile process halts. This is very handy. Once a project comes to an end, I typically enable a very pedantic error level, such that I can make sure that what I contribute is really free of all errors.

I am wondering is there something similar for Latex? To give an example, I would find it desirable if there was a flag that halts compilation on undefined references, rather than having to forge my entire document for ???.

Note

I ended up using the accepted answer. Since references aren't present on the first run, I added a \pedantic flag to my Makefile.

$(FILE)_pedantic.pdf: *.tex
    pdflatex -synctex=1 -shell-escape "\def\pedantic{0} \input{$(FILE).tex}"
    pdflatex -synctex=1 -shell-escape "\def\pedantic{0} \input{$(FILE).tex}"
    bibtex $(FILE)
    makeglossaries $(FILE)
    pdflatex -synctex=1 -shell-escape "\def\pedantic{0} \input{$(FILE).tex}"
    pdflatex -synctex=1 -shell-escape "\def\pedantic{1} \input{$(FILE).tex}"

My root.tex file then sets

\if\pedantic1
   \MakeWarningsErrors
\fi

as suggested by the author of the accepted answer.

Answer 1

A simple solution to this problem is to redefine LaTeX's \GenericWarning macro with the more severe \GenericError:

\documentclass{article}

\newcommand\MakeWarningsErrors{%
    \renewcommand\GenericWarning[2]{%
        \GenericError{##1}{##2}{}{}%
    }%
}

\begin{document}
See section \ref{foo} ...

\MakeWarningsErrors
... and section \ref{bar}.
\end{document}

LaTeX will then report the first warning as normal but stop compilation on the second one:

LaTeX Warning: Reference `foo' on page 1 undefined on input line 11.

! LaTeX Warning: Reference `bar' on page 1 undefined.

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