[clang] Thread Safety Analysis: Warn when using negative reentrant capability (PR #141599)

[Aaron Ballman via cfe-commits]

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@@ -4222,6 +4222,11 @@ def warn_fun_requires_lock_precise :
   InGroup<ThreadSafetyPrecise>, DefaultIgnore;
 def note_found_mutex_near_match : Note<"found near match '%0'">;
 
+// Pedantic thread safety warnings enabled by default
+def warn_thread_reentrant_with_negative_capability : Warning<
+  "%0 is marked reentrant but used as a negative capability; this may be contradictory">,
+  InGroup<ThreadSafetyPedantic>, DefaultIgnore;
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AaronBallman wrote:

> Introduce a pedantic warning group, which is enabled by default, to warn about using a reentrant capability as a negative capability: this usage is likely contradictory.

The only attribute in the group is marked `DefaultIgnore`, did you mean to drop that?

https://github.com/llvm/llvm-project/pull/141599