I am working on a tool that deals with BEAM files, and we want to be able to assume the code was compiled with -Werror, so we don't have to repeat validations that are already done by the erl_lint compiler pass.
Is there a way to figure out if the BEAM was built with -Werror?
I'd expect beam_lib:chunks/2 to help here, but unfortunately it doesn't seem to have what I'm looking for:
beam_lib:chunks("sample.beam", [debug_info, attributes, compile_info]).
% the stuff returned says nothing about -Werror, even if I compile with -Werror
It seems that this information would be always stripped
However, if you are in control of compilation process - you can put additional info into beam files, - which will be accessible through M:module_info(compile) and via beam chunks as well.
For example in rebar:
{erl_opts, [debug_info, {compile_info, [{my_key, my_value}]}]}.
And then:
1> my_module:module_info(compile).
[{version,"7.6.6"},
{options,[debug_info, ...
{my_key,my_value}]
The same is true for "discoverability" of this key directly from beam chunks:
2> beam_lib:chunks("my_beam.beam", [compile_info]).
{ok, ... {my_key,my_value}]}]}}
Meaning, that you can "stamp" your beam files with some meta-information easily. So, a workaround may be to stamp those beam files with this mark.