[Mlir-commits] [mlir] [llvm] Shard the public llvm-config.h in multiple files (NFC) (PR #71273)

[Chris B]

llvm-beanz wrote:

> Sorry but I don't think what you're proposing is a good path forward. And I strongly object to making this an MLIR specific thing: it's not.

If MLIR is the only consumer of those values reducing the exposure area of them seems like a good idea.

I didn't see the earlier PR go in, but I don't think those values should have been exposed to LLVM in the first place. Exposing target availability preprocessor macros is a significant shift for LLVM and could lead to violating LLVM's library layering. LLVM has a longstanding convention that code dependent on a target being enabled is contained to the target itself.

It seems to me that sharding the configuration files as this PR does isn't something the community has a clear agreement on. Further, the people with the most experience maintaining the LLVM build system (which this change impacts) are voicing opposition.

https://github.com/llvm/llvm-project/pull/71273