[clang] [clang] Accept lambdas in C++03 as an extensions (PR #73376)

[Nikolas Klauser via cfe-commits]

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@@ -1526,10 +1526,9 @@ bool CXXRecordDecl::isGenericLambda() const {
 
 #ifndef NDEBUG
 static bool allLookupResultsAreTheSame(const DeclContext::lookup_result &R) {
-  for (auto *D : R)
-    if (!declaresSameEntity(D, R.front()))
-      return false;
-  return true;
+  return llvm::all_of(R, [&](NamedDecl *D) {
+    return D->isInvalidDecl() || declaresSameEntity(D, R.front());
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philnik777 wrote:

See #74110.

https://github.com/llvm/llvm-project/pull/73376