[clang] [compiler-rt] [libcxx] [lld] [lldb] [llvm] [mlir] [polly] python: use raw strings for regex (PR #105990)

[Sam James via cfe-commits]

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@@ -284,7 +284,7 @@ def sync_csv(rows: List[Tuple], from_github: List[PaperInfo]) -> List[Tuple]:
             results.append(gh.for_printing())
             continue
         elif paper.status != gh.status:
-            print(f"We found a CSV row and a Github issue with different statuses:\nrow: {row}\Github issue: {gh}")
+            print(rf"We found a CSV row and a Github issue with different statuses:\nrow: {row}\Github issue: {gh}")
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thesamesam wrote:

I believe @negril is right.

Note that https://docs.python.org/3/whatsnew/3.12.html#other-language-changes doesn't say it's exclusive to regex:
> A backslash-character pair that is not a valid escape sequence now generates a [SyntaxWarning](https://docs.python.org/3/library/exceptions.html#SyntaxWarning), instead of [DeprecationWarning](https://docs.python.org/3/library/exceptions.html#DeprecationWarning). For example, re.compile("\d+\.\d+") now emits a [SyntaxWarning](https://docs.python.org/3/library/exceptions.html#SyntaxWarning) ("\d" is an invalid escape sequence, use raw strings for regular expression: re.compile(r"\d+\.\d+")). In a future Python version, [SyntaxError](https://docs.python.org/3/library/exceptions.html#SyntaxError) will eventually be raised, instead of [SyntaxWarning](https://docs.python.org/3/library/exceptions.html#SyntaxWarning). (Contributed by Victor Stinner in [gh-98401](https://github.com/python/cpython/issues/98401).)

https://github.com/llvm/llvm-project/pull/105990