为什么rebar3无法编译它可以自己编译的依赖项？

Question

I'm trying to compile a module that uses the new xmpp library for ejabberd.

I've a very simple rebar.config file:

{deps, [
    {xmpp, ".*", {git, "https://github.com/processone/xmpp", {tag, "1.1.4"}}}
]}.

When I try to run rebar3 eunit or rebar3 compile I get an error message:

$ rebar3 compile
===> Verifying dependencies...
===> Fetching xmpp ({git,"https://github.com/processone/xmpp",
                                {ref,"c010141487632db1666bcbf64f90f42c0fde50aa"}})
===> Fetching rebar3_hex ({pkg,<<"rebar3_hex">>,<<"3.1.0">>})
===> Downloaded package, caching at /Users/marcp/.cache/rebar3/hex/default/packages/rebar3_hex-3.1.0.tar
===> Compiling rebar3_hex
===> Fetching fast_xml ({pkg,<<"fast_xml">>,<<"1.1.18">>})
===> Downloaded package, caching at /Users/marcp/.cache/rebar3/hex/default/packages/fast_xml-1.1.18.tar
===> Fetching pc ({pkg,<<"pc">>,<<"1.4.0">>})
===> Downloaded package, caching at /Users/marcp/.cache/rebar3/hex/default/packages/pc-1.4.0.tar
===> Compiling pc
===> Fetching stringprep ({pkg,<<"stringprep">>,<<"1.0.7">>})
===> Downloaded package, caching at /Users/marcp/.cache/rebar3/hex/default/packages/stringprep-1.0.7.tar
===> Fetching p1_utils ({pkg,<<"p1_utils">>,<<"1.0.6">>})
===> Downloaded package, caching at /Users/marcp/.cache/rebar3/hex/default/packages/p1_utils-1.0.6.tar
===> Compiling p1_utils
===> Compiling fast_xml
===> Compiling /Users/marcp/Desktop/erlang-test/myapp/_build/default/lib/fast_xml/c_src/fxml.c
===> Compiling /Users/marcp/Desktop/erlang-test/myapp/_build/default/lib/fast_xml/c_src/fxml_stream.c
===> Linking /Users/marcp/Desktop/erlang-test/myapp/_build/default/lib/fast_xml/priv/lib/fxml.so
===> Linking /Users/marcp/Desktop/erlang-test/myapp/_build/default/lib/fast_xml/priv/lib/fxml_stream.so
===> Compiling stringprep
===> Compiling /Users/marcp/Desktop/erlang-test/myapp/_build/default/lib/stringprep/c_src/stringprep.cpp
===> Linking /Users/marcp/Desktop/erlang-test/myapp/_build/default/lib/stringprep/priv/lib/stringprep.so
===> Compiling xmpp
===> Compiling _build/default/lib/xmpp/src/xmpp_util.erl failed
_build/default/lib/xmpp/include/xmpp.hrl:29: can't find include file "fxml.hrl"

However, when I compile this module separately, it works:

$ cd _build/default/lib/xmpp
$ rebar3 compile
===> Fetching rebar3_hex ({pkg,<<"rebar3_hex">>,<<"3.1.0">>})
===> Downloaded package, caching at /Users/marcp/.cache/rebar3/hex/default/packages/rebar3_hex-3.1.0.tar
===> Compiling rebar3_hex
===> Verifying dependencies...
===> Fetching fast_xml ({pkg,<<"fast_xml">>,<<"1.1.18">>})
===> Downloaded package, caching at /Users/marcp/.cache/rebar3/hex/default/packages/fast_xml-1.1.18.tar
===> Fetching pc ({pkg,<<"pc">>,<<"1.4.0">>})
===> Downloaded package, caching at /Users/marcp/.cache/rebar3/hex/default/packages/pc-1.4.0.tar
===> Compiling pc
===> Fetching stringprep ({pkg,<<"stringprep">>,<<"1.0.7">>})
===> Downloaded package, caching at /Users/marcp/.cache/rebar3/hex/default/packages/stringprep-1.0.7.tar
===> Fetching p1_utils ({pkg,<<"p1_utils">>,<<"1.0.6">>})
===> Downloaded package, caching at /Users/marcp/.cache/rebar3/hex/default/packages/p1_utils-1.0.6.tar
===> Skipping p1_utils (from {pkg,<<"p1_utils">>,<<"1.0.6">>,
                                     <<"EF0951DDF38E92B7E479AF4B8DC950DF76AF8C1030432EF68B7FD7AD17C436FE">>}) as an app of the same name has already been fetched
===> Compiling p1_utils
===> Compiling fast_xml
===> Compiling /Users/marcp/Desktop/erlang-test/myapp/_build/default/lib/xmpp/_build/default/lib/fast_xml/c_src/fxml.c
===> Compiling /Users/marcp/Desktop/erlang-test/myapp/_build/default/lib/xmpp/_build/default/lib/fast_xml/c_src/fxml_stream.c
===> Linking /Users/marcp/Desktop/erlang-test/myapp/_build/default/lib/xmpp/_build/default/lib/fast_xml/priv/lib/fxml.so
===> Linking /Users/marcp/Desktop/erlang-test/myapp/_build/default/lib/xmpp/_build/default/lib/fast_xml/priv/lib/fxml_stream.so
===> Compiling stringprep
===> Compiling /Users/marcp/Desktop/erlang-test/myapp/_build/default/lib/xmpp/_build/default/lib/stringprep/c_src/stringprep.cpp
===> Linking /Users/marcp/Desktop/erlang-test/myapp/_build/default/lib/xmpp/_build/default/lib/stringprep/priv/lib/stringprep.so
===> Compiling xmpp

How can I find out what's going on? Is the rebar.config.script of the xmpp library to blame?

Answer 1

It turns out the xmpp cannot be compiled with rebar3 out of the box. I've opened an issue on GitHub .

As a workaround adding the following to my rebar.config file worked:

{overrides, [
    {add, xmpp, [{erl_opts, [{i, "_build/default/lib/fast_xml/include"}]}]}
]}.