Merge branch 'bjorn/compiler/core-erlang-fixes'

* bjorn/compiler/core-erlang-fixes:
  Slightly optimize core_pp
  v3_core: Don't depend on sys_core_fold for cleaning up

3 files changed, 57 insertions, 27 deletions

diff --git a/lib/compiler/src/core_pp.erl b/lib/compiler/src/core_pp.erl
index 88275998be..f34a5c034f 100644
--- a/lib/compiler/src/core_pp.erl
+++ b/lib/compiler/src/core_pp.erl
@@ -37,10 +37,11 @@
 	       indent = 0      :: integer(),
 	       item_indent = 2 :: integer(),
 	       body_indent = 4 :: integer(),
-	       tab_width = 8   :: non_neg_integer(),
 	       line = 0        :: integer(),
 	       clean = true    :: boolean()}).
 
+-define(TAB_WIDTH, 8).
+
 -spec format(cerl:cerl()) -> iolist().
 
 format(Node) ->
@@ -470,37 +471,46 @@ format_map_pair(Op, K, V, Ctxt0) ->
     Ctxt2 = add_indent(Ctxt0, width(Txt, Ctxt1)),
     [Txt,Op,format(V, Ctxt2)].
 
-indent(Ctxt) -> indent(Ctxt#ctxt.indent, Ctxt).
-
-indent(N, _) when N =< 0 -> "";
-indent(N, Ctxt) ->
-    T = Ctxt#ctxt.tab_width,
-    string:chars($\t, N div T, string:chars($\s, N rem T)).
+indent(#ctxt{indent=N}) ->
+    if
+	N =< 0 ->
+	    "";
+	true ->
+	    string:chars($\t, N div ?TAB_WIDTH, spaces(N rem ?TAB_WIDTH))
+    end.
 
 nl_indent(Ctxt) -> [$\n|indent(Ctxt)].
 
+spaces(0) -> "";
+spaces(1) -> " ";
+spaces(2) -> "  ";
+spaces(3) -> "   ";
+spaces(4) -> "    ";
+spaces(5) -> "     ";
+spaces(6) -> "      ";
+spaces(7) -> "       ".
 
 unindent(T, Ctxt) ->
-    unindent(T, Ctxt#ctxt.indent, Ctxt, []).
+    unindent(T, Ctxt#ctxt.indent, []).
 
-unindent(T, N, _, C) when N =< 0 ->
+unindent(T, N, C) when N =< 0 ->
     [T|C];
-unindent([$\s|T], N, Ctxt, C) ->
-    unindent(T, N - 1, Ctxt, C);
-unindent([$\t|T], N, Ctxt, C) ->
-    Tab = Ctxt#ctxt.tab_width,
+unindent([$\s|T], N, C) ->
+    unindent(T, N - 1, C);
+unindent([$\t|T], N, C) ->
+    Tab = ?TAB_WIDTH,
     if N >= Tab ->
-	    unindent(T, N - Tab, Ctxt, C);
+	    unindent(T, N - Tab, C);
        true ->
-	    unindent([string:chars($\s, Tab - N)|T], 0, Ctxt, C)
+	    unindent([spaces(Tab - N)|T], 0, C)
     end;
-unindent([L|T], N, Ctxt, C) when is_list(L) ->
-    unindent(L, N, Ctxt, [T|C]);
-unindent([H|T], _, _, C) ->
+unindent([L|T], N, C) when is_list(L) ->
+    unindent(L, N, [T|C]);
+unindent([H|T], _, C) ->
     [H|[T|C]];
-unindent([], N, Ctxt, [H|T]) ->
-    unindent(H, N, Ctxt, T);
-unindent([], _, _, []) -> [].
+unindent([], N, [H|T]) ->
+    unindent(H, N, T);
+unindent([], _, []) -> [].
 
 
 width(Txt, Ctxt) ->
@@ -509,7 +519,7 @@ width(Txt, Ctxt) ->
     end.
 
 width([$\t|T], A, Ctxt, C) ->
-    width(T, A + Ctxt#ctxt.tab_width, Ctxt, C);
+    width(T, A + ?TAB_WIDTH, Ctxt, C);
 width([$\n|T], _, Ctxt, C) ->
     width(unindent([T|C], Ctxt), Ctxt);
 width([H|T], A, Ctxt, C) when is_list(H) ->
diff --git a/lib/compiler/src/v3_core.erl b/lib/compiler/src/v3_core.erl
index 3299149457..83b3650180 100644
--- a/lib/compiler/src/v3_core.erl
+++ b/lib/compiler/src/v3_core.erl
@@ -510,8 +510,16 @@ unforce(_, Vs) -> Vs.
 
 exprs([E0|Es0], St0) ->
     {E1,Eps,St1} = expr(E0, St0),
-    {Es1,St2} = exprs(Es0, St1),
-    {Eps ++ [E1] ++ Es1,St2};
+    case E1 of
+	#iprimop{name=#c_literal{val=match_fail}} ->
+	    %% Must discard the rest of the body, because it
+	    %% may refer to variables that have not been bound.
+	    %% Example: {ok={error,E}} = foo(), E.
+	    {Eps ++ [E1],St1};
+	_ ->
+	    {Es1,St2} = exprs(Es0, St1),
+	    {Eps ++ [E1] ++ Es1,St2}
+    end;
 exprs([], St) -> {[],St}.
 
 %% expr(Expr, State) -> {Cexpr,[PreExp],State}.
@@ -681,9 +689,14 @@ expr({match,L,P0,E0}, St0) ->
     Fc = fail_clause([Fpat], Lanno, c_tuple([#c_literal{val=badmatch},Fpat])),
     case P2 of
 	nomatch ->
-	    St = add_warning(L, nomatch, St5),
-	    {#icase{anno=#a{anno=Lanno},
-		    args=[E2],clauses=[],fc=Fc},Eps1++Eps2,St};
+	    St6 = add_warning(L, nomatch, St5),
+	    {Expr,Eps3,St} = safe(E1, St6),
+	    Eps = Eps1 ++ Eps2 ++ Eps3,
+	    Badmatch = c_tuple([#c_literal{val=badmatch},Expr]),
+	    Fail = #iprimop{anno=#a{anno=Lanno},
+			    name=#c_literal{val=match_fail},
+			    args=[Badmatch]},
+	    {Fail,Eps,St};
 	Other when not is_atom(Other) ->
 	    {#imatch{anno=#a{anno=Lanno},pat=P2,arg=E2,fc=Fc},Eps1++Eps2,St5}
     end;
diff --git a/lib/compiler/test/match_SUITE.erl b/lib/compiler/test/match_SUITE.erl
index 45d84a7b80..92a9802cad 100644
--- a/lib/compiler/test/match_SUITE.erl
+++ b/lib/compiler/test/match_SUITE.erl
@@ -150,6 +150,9 @@ aliases(Config) when is_list(Config) ->
     none = mixed_aliases({a,42}),
     none = mixed_aliases(42),
 
+    %% Non-matching aliases.
+    {'EXIT',{{badmatch,42},_}} = (catch nomatch_alias(42)),
+
     ok.
 
 str_alias(V) ->
@@ -259,6 +262,10 @@ mixed_aliases(<<X:8>> = {a,X}) -> {c,X};
 mixed_aliases([X] = <<X:8>>) -> {d,X};
 mixed_aliases(_) -> none.
 
+nomatch_alias(I) ->
+    {ok={A,B}} = id(I),
+    {A,B}.
+
 %% OTP-7018.
 
 match_in_call(Config) when is_list(Config) ->