[clang-tools-extra] [clang-tidy] Create a check for signed and unsigned integers comparison (PR #113144)

[Carlos Galvez via cfe-commits]

carlosgalvezp wrote:

Perhaps this has been discussed before, but I think the part about "add qt module" should be added on a separate patch, since adding a brand-new tidy module is a rather big thing.

So this patch could be only about adding the `modernize` check, and a follow-up patch could add the qt module and alias.

https://github.com/llvm/llvm-project/pull/113144