Merge branch 'bjorn/stdlib/fix-erl_lint-bugs/OTP-13157' into maint

* bjorn/stdlib/fix-erl_lint-bugs/OTP-13157:
  Extend erl_lint:format_error/1 to handle bittype mismatches
  erl_lint_SUITE: Add smoke test of format_error/1

2 files changed, 33 insertions, 9 deletions

diff --git a/lib/stdlib/src/erl_lint.erl b/lib/stdlib/src/erl_lint.erl
index c4cb5fdc80..5678e7eebe 100644
--- a/lib/stdlib/src/erl_lint.erl
+++ b/lib/stdlib/src/erl_lint.erl
@@ -293,6 +293,9 @@ format_error({variable_in_record_def,V}) ->
 %% --- binaries ---
 format_error({undefined_bittype,Type}) ->
     io_lib:format("bit type ~w undefined", [Type]);
+format_error({bittype_mismatch,Val1,Val2,What}) ->
+    io_lib:format("conflict in ~s specification for bit field: '~p' and '~p'",
+		  [What,Val1,Val2]);
 format_error(bittype_unit) ->
     "a bit unit size must not be specified unless a size is specified too";
 format_error(illegal_bitsize) ->
diff --git a/lib/stdlib/test/erl_lint_SUITE.erl b/lib/stdlib/test/erl_lint_SUITE.erl
index 0424e2b967..5347ccaf1f 100644
--- a/lib/stdlib/test/erl_lint_SUITE.erl
+++ b/lib/stdlib/test/erl_lint_SUITE.erl
@@ -3604,7 +3604,10 @@ bin_syntax_errors(Config) ->
 	      t(<<X/unit:8>>) -> X;
 	      t(<<X:7/float>>) -> X;
 	      t(<< <<_:8>> >>) -> ok;
-	      t(<<(x ! y):8/integer>>) -> ok.
+	      t(<<(x ! y):8/integer>>) -> ok;
+              t(X) ->
+                {<<X/binary-integer>>,<<X/signed-unsigned-integer>>,
+                 <<X/little-big>>,<<X/unit:4-unit:8>>}.
 	    ">>,
 	   [],
 	   {error,[{1,erl_lint,illegal_bitsize},
@@ -3613,7 +3616,12 @@ bin_syntax_errors(Config) ->
 		   {4,erl_lint,{undefined_bittype,bad_type}},
 		   {5,erl_lint,bittype_unit},
 		   {7,erl_lint,illegal_pattern},
-		   {8,erl_lint,illegal_pattern}],
+		   {8,erl_lint,illegal_pattern},
+		   {10,erl_lint,{bittype_mismatch,integer,binary,"type"}},
+		   {10,erl_lint,{bittype_mismatch,unsigned,signed,"sign"}},
+		   {11,erl_lint,{bittype_mismatch,8,4,"unit"}},
+		   {11,erl_lint,{bittype_mismatch,big,little,"endianness"}}
+		  ],
 	    [{6,erl_lint,{bad_bitsize,"float"}}]}}
 	 ],
     [] = run(Config, Ts),
@@ -3920,22 +3928,35 @@ run_test2(Conf, Test, Warnings0) ->
     %% is no reason to produce an output file since we are only
     %% interested in the errors and warnings.
 
-    %% Print warnings, call erl_lint:format_error/1.
+    %% Print warnings, call erl_lint:format_error/1. (But note that
+    %% the compiler will ignore failing calls to erl_lint:format_error/1.)
     compile:file(File, [binary,report|Opts]),
 
     case compile:file(File, [binary|Opts]) of
-        {ok, _M, Code, Ws} when is_binary(Code) -> warnings(File, Ws);
-        {error, [{File,Es}], []} -> {errors, Es, []};
-        {error, [{File,Es}], [{File,Ws}]} -> {error, Es, Ws};
-        {error, [{File,Es1},{File,Es2}], []} -> {errors2, Es1, Es2}
+        {ok, _M, Code, Ws} when is_binary(Code) ->
+	    warnings(File, Ws);
+        {error, [{File,Es}], []} ->
+	    {errors, call_format_error(Es), []};
+        {error, [{File,Es}], [{File,Ws}]} ->
+	    {error, call_format_error(Es), call_format_error(Ws)};
+        {error, [{File,Es1},{File,Es2}], []} ->
+	    {errors2, Es1, Es2}
     end.
 
 warnings(File, Ws) ->
     case lists:append([W || {F, W} <- Ws, F =:= File]) of
-        [] -> [];
-        L -> {warnings, L}
+        [] ->
+	    [];
+        L ->
+	    {warnings, call_format_error(L)}
     end.
 
+call_format_error(L) ->
+    %% Smoke test of format_error/1 to make sure that no crashes
+    %% slip through.
+    _ = [Mod:format_error(Term) || {_,Mod,Term} <- L],
+    L.
+
 fail() ->
     io:format("failed~n"),
     ?t:fail().