c++ standard

[cozzyd]

AraRoot doesn't compile if ROOT is compiled with a standard different than C++11, due to the C++ standard being hardcoded in the CMakeLists. Once I change that to what my ROOT is compiled with (c++17 in this case), AraRoot compiles fine (so there is nothing obviously incompatible with newer C++ standards).

The best course of action is probably to lift the C++ standard from the ROOT_CXX_FLAGS (or ROOT_CXX_STANDARD if new enough ROOT) instead.

[clark2668]

That sounds fine to me -- I think that was put in over 5 years ago back when we were trying to enforce the move from c++03.

[clark2668]

Out of curiosity, why not just jump forward to c++23? That probably does break lots of things?

[cozzyd]

The C++ standard must match what ROOT is compiled with, otherwise things will break. If ROOT supports and is compiled with C++23 then that should be fine! It may still make sense to specify a minimum C++ standard which will then yell at you so you aren't confused by cryptic compiler errors. On Feb 5, 2025 08:40, Brian Clark ***@***.***> wrote: Out of curiosity, why not just jump forward to c++23? That probably does break lots of things? — Reply to this email directly, view it on GitHub<#98 (comment)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/ACGHWKLZ6LRAWEFQP5CR2MT2OIPGTAVCNFSM6AAAAABWQFNH72VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDMMZXGAZTSNBQGQ>. You are receiving this because you authored the thread.Message ID: ***@***.***>

[clark2668]

Enforcing a minimum seems fair enough to me. Can you do that?

[cozzyd]

ok, the first problem is that the FindROOT.cmake is completely ancient and doesn't actually expose ROOT_CXX_FLAGS (or ROOT_CXX_STANDARD). I think we should remove our vendored FindROOT.cmake files so it can use those installed by ROOT, but this may require additional changes to the build system (since ROOT_GENERATE_DICTIONARY is perhaps different).