There is an error in how etags treats quoted function and record names
in Erlang sources.  etags treats the quotes a part of the name, which is
incorrect and prevents xref-find-definitions from working.

In Erlang, the names of functions and records are "atoms".  Here's a
description of an atom, from "Erlang Handbook"
(http://opensource.erlang-solutions.com/erlang-handbook/):

> An atom is a symbolic name, also known as a literal. Atoms begin with
> a lower-case letter, and may contain alphanumeric characters,
> underscores (_) or at-signs (@). Alternatively atoms can be specified
> by enclosing them in single quotes ('), necessary when they start with
> an uppercase character or contain characters other than underscores
> and at-signs.

Note that the quotes around quoted atoms are not part of the name.  That
is, the following two strings represent the same atom: xyzzy 'xyzzy'
Because etags currently treats the quotes as part of the name, an
attempt to look up the name using the unquoted form will fail.  I have
created a patch to fix this bug.

Attached is the patch (etags.patch), an example Erlang source file that
demonstrates the bug (test.erl), a TAGS file generated from the current
etags program (TAGS), and a TAGS file generated from the patched etags
program (TAGS.new).
-- 
David Hull

In GNU Emacs 25.1.1 (x86_64-apple-darwin13.4.0, NS appkit-1265.21 Version
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 of 2016-09-20 built on builder10-9.porkrind.org
Windowing system distributor 'Apple', version 10.3.1504
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