skip loading comment ranges if one of them was invalid

Author: QuietMisdreavus

lib/AST/RawComment.cpp

@@ -156,6 +156,11 @@ RawComment Decl::getRawComment(bool SerializedOK) const {
           for (const auto &Range : CachedLocs->DocRanges) {
             if (Range.isValid()) {
               SRCs.push_back({ Range, Context.SourceMgr });
+            } else {
+              // if we've run into an invalid range, don't bother trying to load any of
+              // the other comments
+              SRCs.clear();
+              break;
             }
           }
           auto RC = RawComment(Context.AllocateCopy(llvm::makeArrayRef(SRCs)));