[clang] Add Clang attribute to ensure that fields are initialized explicitly (PR #102040)

[Erich Keane via cfe-commits]

================
@@ -2837,6 +2837,10 @@ bool QualType::hasNonTrivialToPrimitiveCopyCUnion(const RecordDecl *RD) {
   return RD->hasNonTrivialToPrimitiveCopyCUnion();
 }
 
+bool QualType::hasUninitializedExplicitInitFields(const RecordDecl *RD) {
----------------
erichkeane wrote:

Right, I would expect that.  I'm just a little shocked we have something like this that has nothing to do with `QualType` in `QualType`.  I DO note however that this doesn't seem to be called anywhere?  Is it actually NEEDED?

https://github.com/llvm/llvm-project/pull/102040