File 0234-beam_call_types-Fix-erlang-band-2-range-ca... of Package erlang

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File 0234-beam_call_types-Fix-erlang-band-2-range-calculation.patch of Package erlang

From bb3d99c74ec66ec0d96b7e71b849c5bda4460464 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?John=20H=C3=B6gberg?= <john@erlang.org>
Date: Wed, 25 Nov 2020 15:47:25 +0100
Subject: [PATCH 2/2] beam_call_types: Fix erlang:band/2 range calculation

I forgot to clamp the maximum, sometimes resulting in a nonsense
type that failed to validate.
---
 lib/compiler/src/beam_call_types.erl  | 2 +-
 lib/compiler/test/beam_type_SUITE.erl | 5 +++++
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/lib/compiler/src/beam_call_types.erl b/lib/compiler/src/beam_call_types.erl
index f4065b2e15..7433d02940 100644
--- a/lib/compiler/src/beam_call_types.erl
+++ b/lib/compiler/src/beam_call_types.erl
@@ -730,7 +730,7 @@ erlang_band_type_1(LHS, Int) ->
             {Intersection, Union} = range_masks(Min0, Max0),
 
             Min = Intersection band Int,
-            Max = min(Max0, Union band Int),
+            Max = max(Min, min(Max0, Union band Int)),
 
             #t_integer{elements={Min,Max}};
         #t_integer{} when Int >= 0 ->
diff --git a/lib/compiler/test/beam_type_SUITE.erl b/lib/compiler/test/beam_type_SUITE.erl
index 5189afde58..5f002f9541 100644
--- a/lib/compiler/test/beam_type_SUITE.erl
+++ b/lib/compiler/test/beam_type_SUITE.erl
@@ -90,6 +90,8 @@ integers(_Config) ->
 
     house = do_integers_7(),
 
+    {'EXIT',{badarith,_}} = (catch do_integers_8()),
+
     ok.
 
 do_integers_1(B0) ->
@@ -155,6 +157,9 @@ do_integers_7() ->
             house
     end.
 
+do_integers_8() ->
+    -1 band ((0 div 0) band 0).
+
 numbers(_Config) ->
     Int = id(42),
     true = is_integer(Int),
-- 
2.26.2

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File 0234-beam_call_types-Fix-erlang-band-2-range-calculation.patch of Package erlang

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