Getting further with Dialyzer

So in the previous post, I was able to compile modules in a way in which they could be analyzed with Dialyzer:

I installed erlang myself from source, so I set my ERL_TOP to where I built it from:
philip@desktop:~/s_server/src$ export ERL_TOP=~/Packages/otp




Now to built a PLT (Persistent Lookup Table).  I only include erlang applications which my application depends on:

philip@desktop:~/s_server/src$ dialyzer --build_plt -r . $ERL_TOP/lib/stdlib/ebin $ERL_TOP/lib/kernel/ebin

This took about 12 min for me using a quite old machine (P4 2.6 GHz).



Now I create my own PLT which is a combination of the previous PLT plus the PLT generated from my own code:

philip@desktop:~/s_server/src$ dialyzer --add_to_plt -r . --output_plt s_server.plt

Finally I can analyse my own code which is in my current directory:

philip@desktop:~/s_server/src$ dialyzer --plt s_server.plt -r .
  Checking whether the PLT s_server.plt is up-to-date... yes
  Proceeding with analysis...
s_server_tests.erl:14: The variable __V can never match since previous clauses completely covered the type 'true'
s_server_tests.erl:16: The variable __V can never match since previous clauses completely covered the type 'true'
s_server_tests.erl:48: The variable _ can never match since previous clauses completely covered the type 'false'
Unknown functions:
  eunit:test/1
 done in 0m1.17s
done (warnings were emitted)

The warnings which I received were in the eunit macros, and not in the actual code which I wanted to analyse.  It would be nice if there was a way to suppress these.

First steps with dialyzer

Today I tried to use dialyzer on my s_server module.  Don't  worry if you have not read any of my posts about this module, it doesn't do any thing useful !

At first I tried to analyse my test module:

philip@desktop:s_server/src$ erlc +debug_info s_server_tests.erl

philip@desktop:s_server/src$ dialyzer -c s_server_tests.erl --build_plt

Which gave me this result:

dialyzer: {dialyzer_error,"Byte code compiled with debug_info is needed to build the PLT"}
[{dialyzer_options,check_output_plt,1,
                   [{file,"dialyzer_options.erl"},{line,86}]},
 {dialyzer_options,postprocess_opts,1,
                   [{file,"dialyzer_options.erl"},{line,75}]},
 {dialyzer_options,build,1,[{file,"dialyzer_options.erl"},{line,63}]},
 {dialyzer_cl_parse,cl,1,[{file,"dialyzer_cl_parse.erl"},{line,218}]},
 {dialyzer_cl_parse,start,0,[{file,"dialyzer_cl_parse.erl"},{line,46}]},
 {dialyzer,plain_cl,0,[{file,"dialyzer.erl"},{line,60}]},
 {init,start_it,1,[]},
 {init,start_em,1,[]}]

The problem actually was that I should have given the beam files to dialyzer to analyse e.g.

philip@desktop:s_server/src$ dialyzer -c s_server_tests.beam --build_plt
  Creating PLT /home/philip/.dialyzer_plt ...
Unknown functions:
  eunit:test/1
  s_server:ping/0
  s_server:start_link/0
  s_server:stop/0
 done in 0m0.40s
done (passed successfully)