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

[Bill Wendling via cfe-commits]

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@@ -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:

Maybe? The `isFlexibleArrayMemberLike` methods are more in depth analysis of the struct and checks against the `-fstrict-flex-arrays=` flag, so it's a more expensive call. But if the `hasFlexibleArrayMember` is always set "correctly," then it's probably sufficient.

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