From 1ae0b6c0bf9c389bcf9bdf266591cb1e17e80a15 Mon Sep 17 00:00:00 2001
From: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date: Tue, 21 Mar 2006 16:28:49 -0300
Subject: [PATCH] BUG: should copy the union, not (some of) its fields

---
 bugs    | 42 ++++++++++++++++++++++++++++++++++++++++++
 lcode.c | 14 ++++++--------
 2 files changed, 48 insertions(+), 8 deletions(-)

diff --git a/bugs b/bugs
index 27bf71d0..e9ea6b73 100644
--- a/bugs
+++ b/bugs
@@ -797,3 +797,45 @@ patch = [[
 
 }
 
+
+
+-----------------------------------------------------------------
+-- Lua 5.1
+
+Bug{
+what = [[In 16-bit machines, expressions and/or with numeric constants as the
+right operand may result in weird values]],
+
+report = [[Andreas Stenius, 15/03/2006]],
+
+example = [[
+print(false or 0)   -- on 16-bit machines
+]],
+
+patch = [[
+* lcode.c:
+@@ -731,17 +731,15 @@
+     case OPR_AND: {
+       lua_assert(e1->t == NO_JUMP);  /* list must be closed */
+       luaK_dischargevars(fs, e2);
+-      luaK_concat(fs, &e1->f, e2->f);
+-      e1->k = e2->k; e1->u.s.info = e2->u.s.info;
+-      e1->u.s.aux = e2->u.s.aux; e1->t = e2->t;
++      luaK_concat(fs, &e2->f, e1->f);
++      *e1 = *e2;
+       break;
+     }
+     case OPR_OR: {
+       lua_assert(e1->f == NO_JUMP);  /* list must be closed */
+       luaK_dischargevars(fs, e2);
+-      luaK_concat(fs, &e1->t, e2->t);
+-      e1->k = e2->k; e1->u.s.info = e2->u.s.info;
+-      e1->u.s.aux = e2->u.s.aux; e1->f = e2->f;
++      luaK_concat(fs, &e2->t, e1->t);
++      *e1 = *e2;
+       break;
+     }
+]],
+
+}
+
diff --git a/lcode.c b/lcode.c
index feaad660..b8ba2a98 100644
--- a/lcode.c
+++ b/lcode.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lcode.c,v 2.23 2005/11/25 13:29:32 roberto Exp roberto $
+** $Id: lcode.c,v 2.24 2005/12/22 16:19:56 roberto Exp roberto $
 ** Code generator for Lua
 ** See Copyright Notice in lua.h
 */
@@ -731,17 +731,15 @@ void luaK_posfix (FuncState *fs, BinOpr op, expdesc *e1, expdesc *e2) {
     case OPR_AND: {
       lua_assert(e1->t == NO_JUMP);  /* list must be closed */
       luaK_dischargevars(fs, e2);
-      luaK_concat(fs, &e1->f, e2->f);
-      e1->k = e2->k; e1->u.s.info = e2->u.s.info;
-      e1->u.s.aux = e2->u.s.aux; e1->t = e2->t;
+      luaK_concat(fs, &e2->f, e1->f);
+      *e1 = *e2;
       break;
     }
     case OPR_OR: {
       lua_assert(e1->f == NO_JUMP);  /* list must be closed */
       luaK_dischargevars(fs, e2);
-      luaK_concat(fs, &e1->t, e2->t);
-      e1->k = e2->k; e1->u.s.info = e2->u.s.info;
-      e1->u.s.aux = e2->u.s.aux; e1->f = e2->f;
+      luaK_concat(fs, &e2->t, e1->t);
+      *e1 = *e2;
       break;
     }
     case OPR_CONCAT: {
@@ -750,7 +748,7 @@ void luaK_posfix (FuncState *fs, BinOpr op, expdesc *e1, expdesc *e2) {
         lua_assert(e1->u.s.info == GETARG_B(getcode(fs, e2))-1);
         freeexp(fs, e1);
         SETARG_B(getcode(fs, e2), e1->u.s.info);
-        e1->k = e2->k; e1->u.s.info = e2->u.s.info;
+        e1->k = VRELOCABLE; e1->u.s.info = e2->u.s.info;
       }
       else {
         luaK_exp2nextreg(fs, e2);  /* operand must be on the 'stack' */