Always discard at least 1 entry in new RNGs #3168
Merged
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Submission Checklist
./runTests.py src/test/unit
make cpplint
Summary
This makes it so at least 1 entry is discarded from new RNG instances, even when
chain == 0
Intended Effect
Closes #3167
How to Verify
See https://godbolt.org/z/G953v67c4 and the model/code provided in #3167
Side Effects
RNG seeds from previous versions of Stan will have different behavior for chain_id 0 and in the transformed data block. Users who did not use
_rng
functions in transformed data or manually set their chain id to 0 will not observe different behavior.Documentation
None
Copyright and Licensing
Please list the copyright holder for the work you are submitting (this will be you or your assignee, such as a university or company):
Simons Foundation
By submitting this pull request, the copyright holder is agreeing to license the submitted work under the following licenses: