[clang] [Driver][BoundsSafety] Add -fbounds-safety-experimental flag (PR #70480)

[Fangrui Song via cfe-commits]

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@@ -0,0 +1,25 @@
+// RUN: not %clang -fbounds-safety-experimental -x c++ %s 2>&1 | FileCheck -check-prefix ERR %s
+
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MaskRay wrote:

We use a terse style and use a blank line to group different sets of tests. Here the blank line use is unnecessary and harms readability IMO.

https://github.com/llvm/llvm-project/pull/70480