erts: Correct conversion of MIN_SMALL numeral to fixnum

list_to_integer and binary_to_integer returned un-normalized bignum for
-134217728 on 32-bit and -576460752303423488 on 64-bit.

Thanks to Jesper Louis Andersen, Mikael Pettersson
and Anthony Ramine for report, initial patch and optimization suggestion.

2 files changed, 13 insertions, 11 deletions

diff --git a/erts/emulator/beam/bif.c b/erts/emulator/beam/bif.c
index fcbeb6cf5c..b835946729 100644
--- a/erts/emulator/beam/bif.c
+++ b/erts/emulator/beam/bif.c
@@ -1,7 +1,7 @@
 /*
  * %CopyrightBegin%
  *
- * Copyright Ericsson AB 1996-2013. All Rights Reserved.
+ * Copyright Ericsson AB 1996-2014. All Rights Reserved.
  *
  * The contents of this file are subject to the Erlang Public License,
  * Version 1.1, (the "License"); you may not use this file except in
@@ -2887,9 +2887,6 @@ static int do_list_to_integer(Process *p, Eterm orig_list,
 	     res = big_plus_small(res, m, hp);
 	 }
 
-	 if (is_big(res))  /* check if small */
-	     res = big_plus_small(res, 0, hp); /* includes conversion to small */
-	 
 	 if (neg) {
 	     if (is_small(res))
 		 res = make_small(-signed_val(res));
@@ -2899,8 +2896,12 @@ static int do_list_to_integer(Process *p, Eterm orig_list,
 	     }
 	 }
 
-	 if (is_big(res)) {
-	     hp += (big_arity(res)+1);
+	 if (is_not_small(res)) {
+	     res = big_plus_small(res, 0, hp); /* includes conversion to small */
+
+	     if (is_not_small(res)) {
+		 hp += (big_arity(res)+1);
+	     }
 	 }
 	 HRelease(p,hp_end,hp);
      }
diff --git a/erts/emulator/beam/big.c b/erts/emulator/beam/big.c
index e62caa6b22..a8710dd910 100644
--- a/erts/emulator/beam/big.c
+++ b/erts/emulator/beam/big.c
@@ -2675,9 +2675,6 @@ Eterm erts_chars_to_integer(Process *BIF_P, char *bytes,
 	res = big_plus_small(res, m, hp);
     }
 
-    if (is_big(res)) /* check if small */
-	res = big_plus_small(res, 0, hp); /* includes conversion to small */
-
     if (neg) {
 	if (is_small(res))
 	    res = make_small(-signed_val(res));
@@ -2687,8 +2684,12 @@ Eterm erts_chars_to_integer(Process *BIF_P, char *bytes,
 	}
     }
 
-    if (is_big(res)) {
-	hp += (big_arity(res) + 1);
+    if (is_not_small(res)) {
+	res = big_plus_small(res, 0, hp); /* includes conversion to small */
+
+	if (is_not_small(res)) {
+	    hp += (big_arity(res) + 1);
+	}
     }
     HRelease(BIF_P, hp_end, hp);
     goto bytebuf_to_integer_1_done;