fix serializer bug in undefined fields in immutables

base/serialize.jl

@@ -534,7 +534,7 @@ function deserialize(s, t::DataType)
  nf = length(t.names)
  if nf == 0
  return ccall(:jl_new_struct, Any, (Any,Any...), t)
- elseif !t.mutable
+ elseif isbits(t)
  if nf == 1
  return ccall(:jl_new_struct, Any, (Any,Any...), t, deserialize(s))
  elseif nf == 2
@@ -548,15 +548,14 @@ function deserialize(s, t::DataType)
  return ccall(:jl_new_struct, Any, (Any,Any...), t, f1, f2, f3)
  else
  flds = Any[ deserialize(s) for i = 1:nf ]
- return ccall(:jl_new_structv, Any, (Any,Ptr{Void},UInt32),
- t, flds, nf)
+ return ccall(:jl_new_structv, Any, (Any,Ptr{Void},UInt32), t, flds, nf)
  end
  else
  x = ccall(:jl_new_struct_uninit, Any, (Any,), t)
  for i in 1:length(t.names)
  tag = int32(read(s, UInt8))
  if tag==0 || !is(deser_tag[tag], UndefRefTag)
- setfield!(x, i, handle_deserialize(s, tag))
+ ccall(:jl_set_nth_field, Void, (Any, Csize_t, Any), x, i-1, handle_deserialize(s, tag))
  end
  end
  return x

test/serialize.jl

@@ -263,4 +263,13 @@ create_serialization_stream() do s # user-defined type array
  r = deserialize(s)
  @test r.state == :failed
  @test isa(t.exception, ErrorException)
-end
+end
+
+# corner case: undefined inside immutable type
+create_serialization_stream() do s
+ serialize(s, Nullable{Any}())
+ seekstart(s)
+ n = deserialize(s)
+ @test isa(n, Nullable)
+ @test !isdefined(n, :value)
+end