clang 22.1.0 dislikes the use of __COUNTER__ with cpp standard 23

[bgemmill]

When compiling tests with boost test and clang 22.1.0 from the llvm apt repository, clang emits a lot of Wc2y-extensions warnings around boost::test's use of the __COUNTER__ macro.

While I've added -Wno-c2y-extensions to my project to silence this, can the fallback of LINE be used if the c++ standard is set at 23?

[mborland]

Well that's annoying, since that macro has been in Clang since 3.0. __COUNTER__ and __LINE__ aren't exactly the same; it's probably best that I just wrap the warning suppression internally.

[bgemmill]

I'm with you that this is a bit annoying, I discovered this when moving from clang 21 to 22 this morning and it's not clear why __COUNTER__ is now treated differently.

[mborland]

__COUNTER__ was standardized for C++2y, and Clang 22 added official support.