[clang] [Clang] disallow # operators in attribute argument lists (PR #147308)

[Corentin Jabot via cfe-commits]

cor3ntin wrote:

My preference would be to be maximally useful (ie accept almost any token), but a few tokens are problematic. namely `#` and `\`. 

Consider

````
[[foo(#\)]]

[[foo(
#
\
)]]
``` 

Given that, I think it's fairly safe to disable `#` and go with this PR. On the flip side, I don't think there is any urgency.




 

https://github.com/llvm/llvm-project/pull/147308