diff --git a/clang-tools-extra/clang-tidy/modernize/LoopConvertCheck.cpp b/clang-tools-extra/clang-tidy/modernize/LoopConvertCheck.cpp
--- a/clang-tools-extra/clang-tidy/modernize/LoopConvertCheck.cpp
+++ b/clang-tools-extra/clang-tidy/modernize/LoopConvertCheck.cpp
@@ -313,6 +313,8 @@
   const auto *Member = dyn_cast<MemberExpr>(TheCall->getCallee());
   if (!Member)
     return nullptr;
+  if (!Member->getMemberDecl()->getDeclName().isIdentifier())
+    return nullptr;
   StringRef Name = Member->getMemberDecl()->getName();
   if (!Name.consume_back(IsBegin ? "begin" : "end"))
     return nullptr;
@@ -544,6 +546,7 @@
   std::vector<FixItHint> FixIts;
   if (VarNameFromAlias) {
     const auto *AliasVar = cast<VarDecl>(AliasDecl->getSingleDecl());
+    assert(AliasVar->getDeclName().isIdentifier());
     VarName = AliasVar->getName().str();
 
     // Use the type of the alias if it's not the same