diff --git a/runtime/lib/double.dart b/runtime/lib/double.dart
index 10bda5de1a6..012ffc5f38e 100644
--- a/runtime/lib/double.dart
+++ b/runtime/lib/double.dart
@@ -103,6 +103,8 @@ class Double implements double {
   bool isNaN() native "Double_isNaN";
 
   double abs() {
+    // Handle negative 0.0.
+    if (this == 0.0) return 0.0;  
     return this < 0.0 ? -this : this;
   }
 
@@ -139,7 +141,7 @@ class Double implements double {
     String s = "";
 
     // Step 6.
-    if (x.isNegative()) {
+    if (x.isNegative() && x != 0.0) {
       s = "-";
       x = -x;
     }
@@ -192,9 +194,30 @@ class Double implements double {
   String toRadixString(int radix) {
     throw "Double.toRadixString unimplemented.";
   }
+
+  // Order is: NaN > Infinity > ... > 0.0 > -0.0 > ... > -Infinity.
   int compareTo(Comparable other) {
-    if (this == other) return 0;
-    if (this < other) return -1;
-    return 1;
+    final int EQUAL = 0, LESS = -1, GREATER = 1;
+    if (this < other) {
+      return LESS;
+    } else if (this > other) {
+      return GREATER;
+    } else if (this == other) {
+      if (this == 0.0) {
+        bool thisIsNegative = isNegative();
+        bool otherIsNegative = other.isNegative();
+        if (thisIsNegative == otherIsNegative) {
+          return EQUAL;
+        }
+        return thisIsNegative ? LESS : GREATER;
+      } else {
+        return EQUAL;
+      }
+    } else if (isNaN()) {
+      return other.isNaN() ? EQUAL : GREATER;
+    } else {
+      // Other is NaN.
+      return LESS;
+    }
   }
 }
diff --git a/runtime/vm/ast.cc b/runtime/vm/ast.cc
index 15117c173ce..6de5e519ba6 100644
--- a/runtime/vm/ast.cc
+++ b/runtime/vm/ast.cc
@@ -93,8 +93,8 @@ AstNode* LiteralNode::ApplyUnaryOp(Token::Kind unary_op_kind) {
       Double& dbl = Double::Handle();
       dbl ^= literal().raw();
       // Preserve negative zero.
-      const Instance& literal =
-          Instance::ZoneHandle(Double::New(0.0 - dbl.value()));
+      double new_value = (dbl.value() == 0.0) ? -0.0 : (0.0 - dbl.value());
+      const Instance& literal = Instance::ZoneHandle(Double::New(new_value));
       return new LiteralNode(this->token_index(), literal);
     }
   }
diff --git a/tests/co19/co19-runtime.status b/tests/co19/co19-runtime.status
index bf8df23ef45..97384b674dc 100644
--- a/tests/co19/co19-runtime.status
+++ b/tests/co19/co19-runtime.status
@@ -4,6 +4,7 @@
 
 prefix co19
 
+
 # Flaky tests, see http://code.google.com/p/co19/issues/detail?id=4
 LibTest/core/StopWatch/elapsedInMs/StopWatch/elapsedInMs/A01/t01: Skip
 LibTest/core/StopWatch/elapsedInUs/StopWatch/elapsedInUs/A01/t01: Skip
@@ -12,6 +13,12 @@ LibTest/core/StopWatch/stop/StopWatch/stop/A01/t01: Skip
 
 
 [ $component == vm ]
+
+LibTest/core/double/isNegative/double/isNegative/A01/t01: Fail  # Issue 6
+LibTest/core/double/operatorDivision/double/operatorDivision/A01/t05: Fail  # Issue 7
+LibTest/core/double/operator~div/double/operator~div/A01/t05: Fail  # Issue 7
+LibTest/core/Math/atan2/Math/atan2/A01/t03: Fail  # Issue 8
+
 LangGuideTest/02_Language_Constructs/02_1_Class/02_1_Class_Const_Expressions/A04/t01: Fail # Bug 5371433
 LangGuideTest/02_Language_Constructs/02_1_Class/02_1_Class_Construction/A10/t01: Fail # Bug 5371433
 LangGuideTest/02_Language_Constructs/02_5_Meaning_of_Names/Examples/A02/t01: Fail # Bug 5371433
@@ -70,7 +77,6 @@ LibTest/core/Queue/some/Queue/some/A01/t06: Fail
 LibTest/core/RegExp/firstMatch/Pattern_semantics/15.10.2.10_CharacterEscape/RegExp/firstMatch/CharacterEscape/A06/t02: Fail
 LibTest/core/StringBuffer/isEmpty/StringBuffer/isEmpty/A01/t01: Fail
 
-
 # List.fromList has been removed.
 LibTest/core/List/List.fromList/*: Fail
 
@@ -214,8 +220,6 @@ LibTest/core/StringBuffer/add/StringBuffer/add/A02/t01: Fail
 LibTest/core/Strings/concatAll/Strings/concatAll/A03/t01: crash
 LibTest/core/Strings/join/Strings/join/A03/t01: crash
 LibTest/core/TypeError/srcType/TypeError/srcType/A01/t01: Fail
-LibTest/core/double/compareTo/double/compareTo/A01/t02: Fail
-LibTest/core/double/compareTo/double/compareTo/A01/t03: Fail
 LibTest/core/double/isOdd/double/isOdd/A01/t02: Fail
 LibTest/core/double/operator%/double/operator%/A01/t06: Fail
 LibTest/core/double/operatorAddition/double/operatorAddition/A01/t02: Fail
diff --git a/tests/corelib/corelib.status b/tests/corelib/corelib.status
index d9541149735..b083b8c3117 100644
--- a/tests/corelib/corelib.status
+++ b/tests/corelib/corelib.status
@@ -6,7 +6,6 @@ prefix corelib
 
 [ $component == vm || $component == dartium ]
 UnicodeTest: Fail        # Bug 5163868
-DoubleCompareTest: Fail  # Bug 5427703
 *DartcTest: Skip
 
 [ $arch == ia32 ]