[clang] [BoundsSafety] Allow 'counted_by' attribute on pointers in structs in C (PR #90786)

[Bill Wendling via cfe-commits]

================
@@ -631,6 +631,18 @@ bool Type::isStructureType() const {
   return false;
 }
 
+bool Type::isStructureTypeWithFlexibleArrayMember() const {
+  const auto *RT = getAs<RecordType>();
+  if (!RT)
+    return false;
+  const auto *Decl = RT->getDecl();
+  if (!Decl->isStruct())
+    return false;
+  if (!Decl->hasFlexibleArrayMember())
+    return false;
+  return true;
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bwendling wrote:

The last three lines could be simplified as:

```c
return Decl->hasFlexibleArrayMember();
```

https://github.com/llvm/llvm-project/pull/90786