From 45537dc582a4fe44a3407e97acb0e1e391fdcd6d Mon Sep 17 00:00:00 2001 From: Stavros Aronis Date: Sun, 20 Mar 2011 23:43:53 +0200 Subject: Suppress some warnings about generation of non-returning funs No warnings are emitted for funs that are non-returning when the function that generates them has a contract that specifies that it will return such a non-returning fun. The actual bug, reported by Tuncer Ayaz and simplified by Maria Christakis is included in Dialyzer's tests. --- lib/dialyzer/src/dialyzer_dataflow.erl | 29 ++- .../test/small_SUITE_data/results/failing_funs | 20 ++ .../test/small_SUITE_data/src/failing_funs.erl | 250 +++++++++++++++++++++ .../test/small_SUITE_data/src/rebar_no_return.erl | 19 ++ 4 files changed, 317 insertions(+), 1 deletion(-) create mode 100644 lib/dialyzer/test/small_SUITE_data/results/failing_funs create mode 100644 lib/dialyzer/test/small_SUITE_data/src/failing_funs.erl create mode 100644 lib/dialyzer/test/small_SUITE_data/src/rebar_no_return.erl (limited to 'lib') diff --git a/lib/dialyzer/src/dialyzer_dataflow.erl b/lib/dialyzer/src/dialyzer_dataflow.erl index df411342cb..659297f993 100644 --- a/lib/dialyzer/src/dialyzer_dataflow.erl +++ b/lib/dialyzer/src/dialyzer_dataflow.erl @@ -2952,7 +2952,7 @@ state__get_warnings(#state{tree_map = TreeMap, fun_tab = FunTab, %% Check if the function has a contract that allows this. Warn = case Contract of - none -> true; + none -> not parent_allows_this(FunLbl, State); {value, C} -> GenRet = dialyzer_contracts:get_contract_return(C), not t_is_unit(GenRet) @@ -3440,6 +3440,33 @@ map_pats(Pats) -> end, cerl_trees:map(Fun, Pats). +parent_allows_this(FunLbl, #state{callgraph = Callgraph, plt = Plt} =State) -> + case state__is_escaping(FunLbl, State) of + false -> false; % if it isn't escaping it can't be a return value + true -> + case state__lookup_name(FunLbl, State) of + {_M, _F, _A} -> false; % if it has a name it is not a fun + _ -> + case dialyzer_callgraph:in_neighbours(FunLbl, Callgraph) of + [Parent] -> + case state__lookup_name(Parent, State) of + {_M, _F, _A} = PMFA -> + case dialyzer_plt:lookup_contract(Plt, PMFA) of + none -> false; + {value, C} -> + GenRet = dialyzer_contracts:get_contract_return(C), + case erl_types:t_is_fun(GenRet) of + false -> false; % element of structure? far-fetched... + true -> t_is_unit(t_fun_range(GenRet)) + end + end; + _ -> false % parent should have a name to have a contract + end; + _ -> false % called in other funs? far-fetched... + end + end + end. + classify_returns(Tree) -> case find_terminals(cerl:fun_body(Tree)) of {false, false} -> no_match; diff --git a/lib/dialyzer/test/small_SUITE_data/results/failing_funs b/lib/dialyzer/test/small_SUITE_data/results/failing_funs new file mode 100644 index 0000000000..a1fb22cbc6 --- /dev/null +++ b/lib/dialyzer/test/small_SUITE_data/results/failing_funs @@ -0,0 +1,20 @@ + +failing_funs.erl:101: The created fun has no local return +failing_funs.erl:104: The created fun has no local return +failing_funs.erl:127: The created fun has no local return +failing_funs.erl:135: The created fun has no local return +failing_funs.erl:138: The created fun has no local return +failing_funs.erl:13: Function foo3/0 has no local return +failing_funs.erl:13: The pattern 'b' can never match the type 'a' +failing_funs.erl:161: The created fun has no local return +failing_funs.erl:169: The created fun has no local return +failing_funs.erl:172: The created fun has no local return +failing_funs.erl:17: The pattern 'b' can never match the type 'a' +failing_funs.erl:195: The created fun has no local return +failing_funs.erl:203: The created fun has no local return +failing_funs.erl:206: The created fun has no local return +failing_funs.erl:229: The created fun has no local return +failing_funs.erl:55: The created fun has no local return +failing_funs.erl:62: The created fun has no local return +failing_funs.erl:69: The created fun has no local return +failing_funs.erl:76: The created fun has no local return diff --git a/lib/dialyzer/test/small_SUITE_data/src/failing_funs.erl b/lib/dialyzer/test/small_SUITE_data/src/failing_funs.erl new file mode 100644 index 0000000000..1784c4a494 --- /dev/null +++ b/lib/dialyzer/test/small_SUITE_data/src/failing_funs.erl @@ -0,0 +1,250 @@ +-module(failing_funs). + +-compile(export_all). + +% Crashes with system call. No spec. +foo1() -> halt(). + +% Crashes with system call. With spec. +-spec foo2() -> no_return(). +foo2() -> halt(). + +% Crashes on its own. No spec. +foo3() -> case a of b -> ok end. + +% Crashes on its own. With spec. +-spec foo4() -> no_return(). +foo4() -> case a of b -> ok end. + +% Creates fun that crashes with system call. No spec. +foo5() -> fun() -> halt() end. + +% Creates fun that crashes with system call. With spec. +-spec foo6() -> fun(() -> no_return()). +foo6() -> fun() -> halt() end. + +% Creates fun from named fun that will crash. Neither have spec. +foo7() -> fun foo1/0. + +% Creates fun from named fun that will crash. Has spec. +-spec foo8() -> fun(() -> no_return()). +foo8() -> fun foo1/0. + +% Creates fun from named fun that will crash. Named has spec. +foo9() -> fun foo2/0. + +% Creates fun from named fun that will crash. Both have specs. +-spec foo10() -> fun(() -> no_return()). +foo10() -> fun foo2/0. + +% Creates fun from named fun that will crash. Neither have spec. +foo11() -> fun foo3/0. + +% Creates fun from named fun that will crash. Has spec. +-spec foo12() -> fun(() -> no_return()). +foo12() -> fun foo3/0. + +% Creates fun from named fun that will crash. Named has spec. +foo13() -> fun foo4/0. + +% Creates fun from named fun that will crash. Both have specs. +-spec foo14() -> fun(() -> no_return()). +foo14() -> fun foo4/0. + +% Creates fun calling a named fun that will crash. Neither have spec. +foo15() -> fun() -> foo1() end. + +% Creates fun calling a named fun that will crash. Has spec. +-spec foo16() -> fun(() -> no_return()). +foo16() -> fun() -> foo1() end. + +% Creates fun calling a named fun that will crash. Named has spec. +foo17() -> fun() -> foo2() end. + +% Creates fun calling a named fun that will crash. Both have specs. +-spec foo18() -> fun(() -> no_return()). +foo18() -> fun() -> foo2() end. + +% Creates fun calling a named fun that will crash. Neither have spec. +foo19() -> fun() -> foo3() end. + +% Creates fun calling a named fun that will crash. Has spec. +-spec foo20() -> fun(() -> no_return()). +foo20() -> fun() -> foo3() end. + +% Creates fun calling a named fun that will crash. Named has spec. +foo21() -> fun() -> foo4() end. + +% Creates fun calling a named fun that will crash. Both have specs. +-spec foo22() -> fun(() -> no_return()). +foo22() -> fun() -> foo4() end. + +% Creates two funs with no local return and will return one or die. No spec. +foo23() -> + Bomb = fun() -> halt() end, + case get(42) of + a -> Bomb(); + b -> fun() -> halt() end + end. + +% Creates two funs with no local return and will return one or die. With spec. +-spec foo24() -> fun(() -> no_return()). +foo24() -> + Bomb = fun() -> halt() end, + case get(42) of + a -> Bomb(); + b -> fun() -> halt() end + end. + +% Creates two funs with no local return and will return one or die. No spec. +foo25() -> + Bomb = fun() -> foo1() end, + case get(42) of + a -> Bomb(); + b -> fun() -> foo1() end + end. + +% Creates two funs with no local return and will return one or die. With spec. +-spec foo26() -> fun(() -> no_return()). +foo26() -> + Bomb = fun foo1/0, + case get(42) of + a -> Bomb(); + b -> fun foo1/0 + end. + +% Creates two funs with no local return and will return one or die. No spec. +foo27() -> + Bomb = fun foo1/0, + case get(42) of + a -> Bomb(); + b -> fun foo1/0 + end. + +% Creates two funs with no local return and will return one or die. With spec. +-spec foo28() -> fun(() -> no_return()). +foo28() -> + Bomb = fun() -> foo1() end, + case get(42) of + a -> Bomb(); + b -> fun() -> foo1() end + end. + +% Creates two funs with no local return and will return one or die. No spec. +foo29() -> + Bomb = fun() -> foo2() end, + case get(42) of + a -> Bomb(); + b -> fun() -> foo2() end + end. + +% Creates two funs with no local return and will return one or die. With spec. +-spec foo30() -> fun(() -> no_return()). +foo30() -> + Bomb = fun foo2/0, + case get(42) of + a -> Bomb(); + b -> fun foo2/0 + end. + +% Creates two funs with no local return and will return one or die. No spec. +foo31() -> + Bomb = fun foo2/0, + case get(42) of + a -> Bomb(); + b -> fun foo2/0 + end. + +% Creates two funs with no local return and will return one or die. With spec. +-spec foo32() -> fun(() -> no_return()). +foo32() -> + Bomb = fun() -> foo2() end, + case get(42) of + a -> Bomb(); + b -> fun() -> foo2() end + end. + +% Creates two funs with no local return and will return one or die. No spec. +foo33() -> + Bomb = fun() -> foo3() end, + case get(42) of + a -> Bomb(); + b -> fun() -> foo3() end + end. + +% Creates two funs with no local return and will return one or die. With spec. +-spec foo34() -> fun(() -> no_return()). +foo34() -> + Bomb = fun foo3/0, + case get(42) of + a -> Bomb(); + b -> fun foo3/0 + end. + +% Creates two funs with no local return and will return one or die. No spec. +foo35() -> + Bomb = fun foo3/0, + case get(42) of + a -> Bomb(); + b -> fun foo3/0 + end. + +% Creates two funs with no local return and will return one or die. With spec. +-spec foo36() -> fun(() -> no_return()). +foo36() -> + Bomb = fun() -> foo3() end, + case get(42) of + a -> Bomb(); + b -> fun() -> foo3() end + end. + +% Creates two funs with no local return and will return one or die. No spec. +foo37() -> + Bomb = fun() -> foo4() end, + case get(42) of + a -> Bomb(); + b -> fun() -> foo4() end + end. + +% Creates two funs with no local return and will return one or die. With spec. +-spec foo38() -> fun(() -> no_return()). +foo38() -> + Bomb = fun foo4/0, + case get(42) of + a -> Bomb(); + b -> fun foo4/0 + end. + +% Creates two funs with no local return and will return one or die. No spec. +foo39() -> + Bomb = fun foo4/0, + case get(42) of + a -> Bomb(); + b -> fun foo4/0 + end. + +% Creates two funs with no local return and will return one or die. With spec. +-spec foo40() -> fun(() -> no_return()). +foo40() -> + Bomb = fun() -> foo4() end, + case get(42) of + a -> Bomb(); + b -> fun() -> foo4() end + end. + +% Obtains two funs with no local return and will return one or die. No spec. +foo41() -> + Bomb = foo5(), + case get(42) of + a -> Bomb(); + b -> foo5() + end. + +% Obtains two funs with no local return and will return one or die. With spec. +-spec foo42() -> fun(() -> no_return()). +foo42() -> + Bomb = foo5(), + case get(42) of + a -> Bomb(); + b -> foo5() + end. diff --git a/lib/dialyzer/test/small_SUITE_data/src/rebar_no_return.erl b/lib/dialyzer/test/small_SUITE_data/src/rebar_no_return.erl new file mode 100644 index 0000000000..d3b504ae04 --- /dev/null +++ b/lib/dialyzer/test/small_SUITE_data/src/rebar_no_return.erl @@ -0,0 +1,19 @@ +-module(rebar_no_return). + +-export([t/0]). + +-spec t() -> no_return(). +t() -> + F = log_and_halt("baz"), + F("foo", 123). + +-spec log_and_halt(string()) -> fun((string(),integer()) -> no_return()). +log_and_halt(Msg) -> + fun(_, _) -> + abort(Msg) + end. + +-spec abort(string()) -> no_return(). +abort(Msg) -> + io:format("~s~n", [Msg]), + halt(1). -- cgit v1.2.3