Concrete-ML is currently in beta, and thus may contains bugs or suboptimal APIs.
Before opening an issue or asking for support, we encourage the users to read this documentation to understand common issues and limations of Concrete-ML, as well as checking the outstanding issues on github.
Furthermore, undefined behavior may occur if inputset, which is internally used by the compilation core to set bit widths of some intermediate data, is not sufficiently representative of the future user inputs. With all the inputs in the inputset, it appears that intermediate data can be represented as an n-bit integer. But, for a particular computation, this same intermediate data needs additional bits to be represented. The FHE execution for this computation will result in an incorrect output, as typically occurs in integer overflows in classical programs.
If you didn't find an answer, you can ask a question on the Zama forum, or in the FHE.org discord.
When submitting an issue (here), make sure you can isolate and reproduce the bug, and give us as much information as possible. In addition to the Python script, the following information is useful:
the reproducibility rate you see on your side
any insight you might have on the bug
any workaround you have been able to find
If you would like to contribute to project and send pull requests, take a look at the contributor guide.