[clang] [llvm] [SpecialCaseList] Use glob by default (PR #74809)

[Ellis Hoag via cfe-commits]

ellishg wrote:

> A report from the field: we had an ignorelist that contained `[cfi-vcall|cfi-nvcall|cfi-icall]`.  This was recommended syntax from the documentation (https://releases.llvm.org/17.0.1/tools/clang/docs/SanitizerSpecialCaseList.html)... but it broke with the transition.  This took a significant effort to track down.
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> I see the following issues with the transition:
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> - There was no release note, or any sort of announcement of this breaking change.
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> - No version of clang produces a diagnostic if you use the affected syntax; the behavior just silently changes.
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> - The proposed transition period is extremely short; it's impossible to write an ignorelist that works on both clang 17 and clang 19 if you use any regex/glob features other than "*".

I [announced this change on discourse](https://discourse.llvm.org/t/use-glob-instead-of-regex-for-specialcaselists/71666?u=ellishg) last year. I think others have seen this specific bug before, so maybe I should call out this case in that post. 

https://github.com/llvm/llvm-project/pull/74809