diff --git a/lib/coffee-script/nodes.js b/lib/coffee-script/nodes.js
index c4c00ffc..5635202f 100644
--- a/lib/coffee-script/nodes.js
+++ b/lib/coffee-script/nodes.js
@@ -3033,9 +3033,10 @@
     };
 
     Op.prototype.compileFloorDivision = function(o) {
-      var div, floor;
+      var div, floor, second;
       floor = new Value(new IdentifierLiteral('Math'), [new Access(new PropertyName('floor'))]);
-      div = new Op('/', this.first, this.second);
+      second = this.second.isComplex() ? new Parens(this.second) : this.second;
+      div = new Op('/', this.first, second);
       return new Call(floor, [div]).compileToFragments(o);
     };
 
diff --git a/src/nodes.coffee b/src/nodes.coffee
index 7b906313..73fadbce 100644
--- a/src/nodes.coffee
+++ b/src/nodes.coffee
@@ -2077,7 +2077,8 @@ exports.Op = class Op extends Base
 
   compileFloorDivision: (o) ->
     floor = new Value new IdentifierLiteral('Math'), [new Access new PropertyName 'floor']
-    div = new Op '/', @first, @second
+    second = if @second.isComplex() then new Parens @second else @second
+    div = new Op '/', @first, second
     new Call(floor, [div]).compileToFragments o
 
   compileModulo: (o) ->
diff --git a/test/error_messages.coffee b/test/error_messages.coffee
index b36b029b..8034e4ef 100644
--- a/test/error_messages.coffee
+++ b/test/error_messages.coffee
@@ -416,7 +416,7 @@ test "#3795: invalid escapes", ->
   assertErrorFormat '''
     ///a \\u002 0 space///
   ''', '''
-    [stdin]:1:6: error: invalid escape sequence \\u002 
+    [stdin]:1:6: error: invalid escape sequence \\u002 \n\
     ///a \\u002 0 space///
          ^\^^^^^
   '''
diff --git a/test/operators.coffee b/test/operators.coffee
index eb57e888..9c683aae 100644
--- a/test/operators.coffee
+++ b/test/operators.coffee
@@ -330,7 +330,7 @@ test "floor division operator", ->
 
 test "floor division operator compound assignment", ->
   a = 7
-  a //= 2
+  a //= 1 + 1
   eq 3, a
 
 test "modulo operator", ->