Merge branch 'pan/otp_8579_autoimport_override' into dev

* origin/pan/otp_8579_autoimport_override:
  Update preloaded modules
  Update primary bootstrap
  Remove outcommented code from erl_lint
  Make port_command/3 auto-imported
  Remove (harmless) warnings about min/max in core applications
  Autoimport min/2 and max/2
  Improve coverage of erl_int in testcases
  Change warning to error for nowarn_bif_clash compiler directive
  Add -compile({no_auto_import,[F/A]}) doc to compiler.xml
  Add some testcases to compiler to verify that overriding really happens
  Return nowarn_bif_clash functionality but with warning
  Teach erl_lint to better override BIFs with local functions and imports
  Teach compiler to override autoimport with import
  First prototype for local functions overriding autoimported

OTP-8579  Local functions should override auto-imported

Local and imported functions now override the autoimported
BIFs when the names clash. The pre R14 behaviour was that
autoimported BIFs would override local functions. To avoid
that old programs change behaviour, the following will
generate an error:

Doing a call without explicit module name to a local function
having a name clashing with the name of an autoimported BIF
that was present (and autoimported) before OTP R14A
Explicitly importing a function having a name clashing with
the name of an autoimported BIF that was present (and
autoimported) before OTP R14A Using any form of the old
compiler directive nowarn_bif_clash

If the BIF was added or autoimported in OTP R14A or later,
overriding it with an import or a local function will only
result in a warning,

To resolve clashes, you can either use the explicit module
name erlang to call the BIF, or you can remove the autoimport
of that specific BIF by using the new compiler directive
-compile({no_auto_import,[F/A]})., which makes all calls to
the local or imported function without explicit module name
pass without warnings or errors.

The change makes it possible to add autoimported BIFs without
breaking or silently changing old code in the future. However
some current code ingeniously utilizing the old behaviour or
the nowarn_bif_clash compiler directive, might need changing
to be accepted by the compiler.

1 files changed, 47 insertions, 2 deletions

diff --git a/lib/compiler/test/misc_SUITE.erl b/lib/compiler/test/misc_SUITE.erl
index 126a679724..450a4e279d 100644
--- a/lib/compiler/test/misc_SUITE.erl
+++ b/lib/compiler/test/misc_SUITE.erl
@@ -20,10 +20,23 @@
 
 -export([all/1,init_per_testcase/2,fin_per_testcase/2,
 	 tobias/1,empty_string/1,md5/1,silly_coverage/1,
-	 confused_literals/1,integer_encoding/1]).
+	 confused_literals/1,integer_encoding/1,override_bif/1]).
 	 
 -include("test_server.hrl").
 
+%% For the override_bif testcase.
+%% NB, no other testcases in this testsuite can use these without erlang:prefix!
+-compile({no_auto_import,[abs/1]}).
+-compile({no_auto_import,[binary_part/3]}).
+-compile({no_auto_import,[binary_part/2]}).
+-import(test_lib,[binary_part/2]).
+
+%% This should do no harm (except for fun byte_size/1 which does not, by design, work with import
+-compile({no_auto_import,[byte_size/1]}).
+-import(erlang,[byte_size/1]).
+
+
+
 %% Include an opaque declaration to cover the stripping of
 %% opaque types from attributes in v3_kernel.
 -opaque misc_SUITE_test_cases() :: [atom()].
@@ -42,7 +55,39 @@ fin_per_testcase(Case, Config) when is_atom(Case), is_list(Config) ->
 all(suite) ->
     test_lib:recompile(?MODULE),
     [tobias,empty_string,md5,silly_coverage,confused_literals,
-     integer_encoding].
+     integer_encoding, override_bif].
+
+
+%%
+%% Functions that override new and old bif's
+%%
+abs(_N) ->
+    dummy_abs.
+
+binary_part(_,_,_) ->
+    dummy_bp.
+
+% Make sure that auto-imported BIF's are overridden correctly
+
+override_bif(suite) ->
+    [];
+override_bif(doc) ->
+    ["Test dat local functions and imports override auto-imported BIFs."];
+override_bif(Config) when is_list(Config) ->
+    ?line dummy_abs = abs(1),
+    ?line dummy_bp = binary_part(<<"hello">>,1,1),
+    ?line dummy = binary_part(<<"hello">>,{1,1}),
+    ?line 1 = erlang:abs(1),
+    ?line <<"e">> = erlang:binary_part(<<"hello">>,1,1),
+    ?line <<"e">> = erlang:binary_part(<<"hello">>,{1,1}),
+    F = fun(X) when byte_size(X) =:= 4 ->
+		four;
+	   (X) ->
+		byte_size(X)
+	end,
+    ?line four = F(<<1,2,3,4>>),
+    ?line 5 = F(<<1,2,3,4,5>>),
+    ok.
 
 %% A bug reported by Tobias Lindahl for a development version of R11B.