[clang] Support [[guarded_by(mutex)]] attribute inside C struct (PR #94216)

[Dan Liew via cfe-commits]

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@@ -74,6 +83,15 @@ int get_value(int *p) SHARED_LOCKS_REQUIRED(foo_.mu_){
 
 void unlock_scope(struct Mutex *const *mu) __attribute__((release_capability(**mu)));
 
+// Verify late parsing:
+#ifdef LATE_PARSING
+struct LateParsing {
+  int a_value_defined_before GUARDED_BY(a_mutex_defined_late);
+  struct Mutex *a_mutex_defined_late ACQUIRED_AFTER(a_mutex_defined_very_late);
+  struct Mutex *a_mutex_defined_very_late;
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delcypher wrote:

@pdherbemont Also I can't see any uses of the `LateParsing` struct. It might be worth testing the attributes were parsed. You could do that as a separate AST test or use the `LateParsing` struct in a way that will make the thread safety analysis emit warnings.

https://github.com/llvm/llvm-project/pull/94216