[clang] [APINotes] Refactor APINotesReader to propagate llvm::Error (PR #183812)

[Gábor Horváth via cfe-commits]

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@@ -118,9 +121,13 @@ APINotesManager::loadAPINotes(StringRef Buffer) {
 
   CompiledBuffer = llvm::MemoryBuffer::getMemBufferCopy(
       StringRef(APINotesBuffer.data(), APINotesBuffer.size()));
+
   auto Reader = APINotesReader::Create(std::move(CompiledBuffer), SwiftVersion);
-  assert(Reader && "Could not load the API notes we just generated?");
-  return Reader;
+  if (!Reader) {
+    llvm::consumeError(Reader.takeError());
+    return nullptr;
+  }
+  return std::move(Reader.get());
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Xazax-hun wrote:

Redundant `std::move`?

https://github.com/llvm/llvm-project/pull/183812