Bug introduced in 10.0.0 and fixed in 10.0.1

The bug is also present in 12.2.0 and resolved in 12.3.0 on Mac OS X x86 (64-bit).

If I evaluate, with a fresh kernel


I get

{"rhs", "z"}

I think this is not caused by any packages in $UserBaseDirectory or $BaseDirectory, because if I evaluate the same expression under V9.0.1, which has the same strings for these variables (directories), I get


As expected.

I was wondering if others are getting the same result. rhs and z do not have values, but still I am a bit concerned about the safety of


when certain functions may depend on the existence of these symbols in Global`. For example if I set

sys`f[Global`xxxx_] := Global`xxxx

and evaluate


then the following looks a bit scary

 sys`f // Definition

sys`f still works, but I still think it may lead to trouble (e.g. with Save).

Kirma came up with the nice idea of testing this on the cloud. I get

 MemberQ[CloudEvaluate[Names["Global`*"]], #] & /@ {"z", "rhs"}]

But there are many other symbols in the Global` context there. So, is this a bug?

  • 2
    $\begingroup$ On V10 I get {FOO, list, msgs, rhs, z} $\endgroup$
    – mfvonh
    Commented Jul 12, 2014 at 12:06
  • 3
    $\begingroup$ In v.10.0.0 under Win7 x64 I get {"rhs", "z"}. $\endgroup$ Commented Jul 12, 2014 at 12:47
  • 1
    $\begingroup$ I have seen both {list, msgs, rhs, z} and {"rhs", "z"}. Win-7 64. $\endgroup$ Commented Jul 12, 2014 at 18:37
  • 1
    $\begingroup$ @SjoerdC.deVries reported! $\endgroup$ Commented Jul 13, 2014 at 8:44
  • 4
    $\begingroup$ Seems to be solved in V10.0.1 (Win7-64). $\endgroup$ Commented Sep 17, 2014 at 14:33

1 Answer 1


I reported this problem to Wolfram technical support, and I have received the following response (edited for brevity).

I was able to reproduce the issue you have reported. I have forwarded an incident report to our developers with the information you provided.

I have tagged the question with .


This bug appears to be fixed in V10.0.1


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.