[SYCL] Make __SYCL_COMPILER_VERSION reproducible #19692
Description
Is your feature request related to a problem? Please describe
Currently, __SYCL_COMPILER_VERSION is defined like this:
string(TIMESTAMP __SYCL_COMPILER_VERSION "%Y%m%d")
meaning it is set to the date of compilation. If you compile an old version now, it will over-report its version. Similarly, if the system date is in the past, it will under-report (for example when building in a Nix sandbox, when it is always set to Unix Epoch for reproducibility).
In programs that check #if (__SYCL_COMPILER_VERSION < ...) (like in oneDNN), this may cause incorrect behavior.
Describe the solution you would like
Determine the date through another method. Some ideas:
- Use git to check the date of the latest commit
- Have some auto-updated file with the current date
- Set it via a CMake flag, which CI fills in
Describe alternatives you have considered
n/a
Additional context
No response