I got the files tex.web and pdftex.web from the texlive svn repo. I ran
weave tex.web pdftex tex.tex
which produced a file
tex.pdf with a nicely typeset, cross-referenced listing of the WEB source of TeX.
However, if I do the same process pdftex.web, the resulting file
pdftex.pdf only contains the pages corresponding to the index.
Is there some other combination of commands I need to run, or do I need to edit part of pdftex.web? I tried weaving in the supplied
.ch files, but it didn't seem to make a difference.