gistfile1.diff

diff --git a/vm/builtin/fixnum.cpp b/vm/builtin/fixnum.cpp
index 679c5f1..5d51798 100644
--- a/vm/builtin/fixnum.cpp
+++ b/vm/builtin/fixnum.cpp
@@ -126,7 +126,7 @@ namespace rubinius {
     native_int denominator = other->to_native();
     native_int quotient = div(state, other)->to_native();
     native_int modulo = numerator - denominator * quotient;
-    
+
     if((modulo < 0 && denominator > 0) || (modulo > 0 && denominator < 0)) {
       return Fixnum::from(modulo + denominator);
     } else {
@@ -283,14 +283,20 @@ namespace rubinius {
 
   Integer* Fixnum::left_shift(STATE, Fixnum* bits) {
     native_int shift = bits->to_native();
+    native_int self = to_native();
+
+    if (self == 0) {
+      return Fixnum::from(0);
+    }
+
     if(shift < 0) {
       return right_shift(state, Fixnum::from(-shift));
     }
 
-    native_int self = to_native();
+    native_int check = self > 0 ? self : -self;
 
     if(shift >= (native_int)FIXNUM_WIDTH
-        || self >> ((native_int)FIXNUM_WIDTH - shift) > 0) {
+        || check >> ((native_int)FIXNUM_WIDTH - shift) > 0) {
       return Bignum::from(state, self)->left_shift(state, bits);
     }