================ @@ -0,0 +1,3 @@ +// RUN: %clang_cc1 -std=c++20 -fms-extensions %s +// expected-no-diagnostics +constexpr int x = []{ __noop; return 0; }(); ---------------- cor3ntin wrote: You do not need the define/ifdef/etc https://github.com/llvm/llvm-project/pull/105983