[llvm] Fixes for compile rust code (PR #192134)

[via llvm-commits]

================
@@ -794,6 +794,12 @@ void BTFDebug::visitArrayType(const DICompositeType *CTy, uint32_t &TypeId) {
 
   // Visit array dimensions.
   DINodeArray Elements = CTy->getElements();
+  if (Elements.size() == 0) {
+    // Rust and other languages may emit array types with no dimensions.
+    // Treat as a zero-length array so the type is still registered.
+    auto TypeEntry = std::make_unique<BTFTypeArray>(ElemTypeId, 0);
----------------
4ast wrote:

Not sure whether it makes it easier to read. Will consider for followup.

https://github.com/llvm/llvm-project/pull/192134