[PATCH] D87732: [Support] Provide sys::path::guess_style

[Reid Kleckner via Phabricator via llvm-commits]

rnk added a comment.

I'd prefer it if we didn't have to guess the path style in the first place. Initially I thought the target triple might be able to help us out, but it doesn't, because really you want to know the path style of the file system in use where compilation took place. Normally, clang is the one reading the source files, so whatever clang's host's style is is the right style. These test cases are getting tripped up because compilation is split over two host OSs: Clang's OS and llc's OS. Now I wonder if we shouldn't just persist the path style through the IR module, or even through the assembler if DWARF needs to join paths after assembly.

Separately, I would like LLVM to move in the direction of standardizing on forward slashes in internal representations and data structures. We already convert long paths to UNC style before we call FS APIs on Windows. That's a good point to rewrite to backslashes if we need to. I don't believe any information or capabilities are lost: NTFS filenames may not contain `/` characters. Even if we receive a funky UNC-style path from a user, we can change the slash direction internally, and no information will be lost.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D87732/new/

https://reviews.llvm.org/D87732