Undefined symbol?

[Tofu Ninja via Digitalmars-d-learn]

On Wednesday, 18 February 2015 at 10:47:50 UTC, John Colvin wrote:
> On Wednesday, 18 February 2015 at 08:55:51 UTC, Tofu Ninja 
> wrote:
>> When I compile my project in release dmd suddenly starts 
>> complains about missing symbols that look like they are from 
>> phobos.
>>
>> Symbol Undefined 
>> _D3std9exception134__T12errnoEnforceTbVAyaa50_433a5c445c646d64325c77696e646f77735c62696e5c2e2e5cA7E6C89D7777F0A958C3336C905AF5DE
>>
>> Any idea what is causing it and what a fix might be?
>
> These errors are normally caused by combining object files or 
> libraries that were compiled by different compiler versions. 
> The biggest mistake is accidentally linking to an older/newer 
> version of phobos.

I am not sure what could be the offending obj. I re downloaded 
dmd and phobos(pre compiled for windows), cleaned out all my 
builds and removed all of the tempfiles for dub that I could find.