Huh I thought said I should build twice and com

Question

Huh I thought < theopolis> said I should build twice and compare checksums

Stefano Bonicatti · Answer

Well if it does it s luck Meaning for instance any usage of ` DATE ` ` TIME ` ` FILE ` Link Time Optimization will not get you a deterministic build

Stefano Bonicatti · Answer

There are ways to force known values or fixed seeds for lto which though ok for Linux macOS case we are not using

Stefano Bonicatti · Answer

but we are not doing them

Stefano Bonicatti · Answer

also compiling on a different different path can change the checksum

theopolis · Answer

Agree that maintaining reproducibility is hard and needs a test in the CI We had this with Jenkins but we do have a reproducible build I at least test this on Linux manually when building packages

theopolis · Answer

I might be able to improve my testing it might not removal all artifacts

theopolis · Answer

^ it only removes the source build directories and starts again mostly assuring there are not dirty changes Never used it as a way to confirm my VMs were clean of malfeasance

seph · Answer

Seems weird that my builds i on different VMs did t march

Stefano Bonicatti · Answer

different VMs how

seph · Answer

I started 2 VMs in gcloud Then I ran the steps in parallel Same OS image but otherwise different

seph · Answer

I m not sure this is really actionable

theopolis · Answer

yeah unfortunately not right now