Zero-arity unused functions Dialyzer patch

Dialyzer was not reporting unused functions with 0 arity. This was not
a real issue, until we found out that there could be cases where this
could lead to false warnings. This was the case in "no_local_return.erl".

6 files changed, 19 insertions, 2 deletions

diff --git a/lib/dialyzer/test/options1_SUITE_data/results/compiler b/lib/dialyzer/test/options1_SUITE_data/results/compiler
index e82087ae86..6399e3e36b 100644
--- a/lib/dialyzer/test/options1_SUITE_data/results/compiler
+++ b/lib/dialyzer/test/options1_SUITE_data/results/compiler
@@ -20,6 +20,7 @@ cerl_inline.erl:2333: The pattern 'true' can never match the type 'false'
 cerl_inline.erl:2355: The pattern 'true' can never match the type 'false'
 cerl_inline.erl:238: The pattern 'true' can never match the type 'false'
 cerl_inline.erl:2436: Function filename/1 will never be called
+cerl_inline.erl:244: Function counter_stats/0 will never be called
 cerl_inline.erl:2700: The pattern 'true' can never match the type 'false'
 cerl_inline.erl:2730: The pattern <{F, L, D}, Vs> can never match the type <[1..255,...],[any()]>
 cerl_inline.erl:2738: The pattern <{F, L, D}, Vs> can never match the type <[1..255,...],[any()]>
diff --git a/lib/dialyzer/test/r9c_SUITE_data/results/inets b/lib/dialyzer/test/r9c_SUITE_data/results/inets
index 24cb39e52b..773525eb7f 100644
--- a/lib/dialyzer/test/r9c_SUITE_data/results/inets
+++ b/lib/dialyzer/test/r9c_SUITE_data/results/inets
@@ -8,6 +8,7 @@ http_lib.erl:424: The variable _ can never match since previous clauses complete
 http_lib.erl:438: The variable _ can never match since previous clauses completely covered the type any()
 http_lib.erl:99: Function getHeaderValue/2 will never be called
 httpc_handler.erl:660: Function exit_session_ok/2 has no local return
+httpc_handler.erl:676: Function format_time/0 will never be called
 httpc_manager.erl:145: The pattern {ErrorReply, State2} can never match the type {{'ok',number()},number(),#state{reqid::number()}}
 httpc_manager.erl:160: The pattern {ErrorReply, State2} can never match the type {{'ok',number()},number(),#state{reqid::number()}}
 httpc_manager.erl:478: The pattern {'error', Reason} can never match the type 'ok' | {number(),#session{clientclose::boolean(),pipeline::[],quelength::1}}
diff --git a/lib/dialyzer/test/small_SUITE_data/results/cerl_hipeify b/lib/dialyzer/test/small_SUITE_data/results/cerl_hipeify
index 87bf6f309f..06dc0d63ee 100644
--- a/lib/dialyzer/test/small_SUITE_data/results/cerl_hipeify
+++ b/lib/dialyzer/test/small_SUITE_data/results/cerl_hipeify
@@ -1,4 +1,4 @@
 
 cerl_hipeify.erl:370: Function will never be called
-cerl_hipeify.erl:370: Guard test fun((none()) -> none()) =:= F::{_,_,_} | {_,_,_,_} | {_,_,_,_,_} | {_,_,_,_,_,_} | {_,_,_,_,_,_,_} can never succeed
+cerl_hipeify.erl:370: Guard test fun((none()) -> no_return()) =:= F::{_,_,_} | {_,_,_,_} | {_,_,_,_,_} | {_,_,_,_,_,_} | {_,_,_,_,_,_,_} can never succeed
 cerl_hipeify.erl:641: Function env__new_function_name/2 will never be called
diff --git a/lib/dialyzer/test/small_SUITE_data/results/inf_loop2 b/lib/dialyzer/test/small_SUITE_data/results/inf_loop2
index 7e9972ad98..142e4b2c37 100644
--- a/lib/dialyzer/test/small_SUITE_data/results/inf_loop2
+++ b/lib/dialyzer/test/small_SUITE_data/results/inf_loop2
@@ -1,4 +1,4 @@
 
 inf_loop2.erl:18: Function test/0 has no local return
 inf_loop2.erl:19: The call lists:reverse('gazonk') will never return since it differs in the 1st argument from the success typing arguments: ([any()])
-inf_loop2.erl:22: Function loop/0 has no local return
+inf_loop2.erl:22: Function loop/0 will never be called
diff --git a/lib/dialyzer/test/small_SUITE_data/results/no_local_return b/lib/dialyzer/test/small_SUITE_data/results/no_local_return
new file mode 100644
index 0000000000..6ca1ed51d8
--- /dev/null
+++ b/lib/dialyzer/test/small_SUITE_data/results/no_local_return
@@ -0,0 +1,3 @@
+
+no_local_return.erl:11: Function bar/1 will never be called
+no_local_return.erl:8: Function foo/0 will never be called
diff --git a/lib/dialyzer/test/small_SUITE_data/src/no_local_return.erl b/lib/dialyzer/test/small_SUITE_data/src/no_local_return.erl
new file mode 100644
index 0000000000..4e1a0b015a
--- /dev/null
+++ b/lib/dialyzer/test/small_SUITE_data/src/no_local_return.erl
@@ -0,0 +1,12 @@
+-module(no_local_return).
+
+%% NOTE: No function is exported.  Dialyzer produced a bogus
+%%      'Function foo/0 has no local return' warning
+%% when in fact typer was finding correct return values for both
+%% these functions.
+
+foo() ->
+ bar(42).
+
+bar(X) ->
+ lists:duplicate(X, gazonk).