llvm-project/clang/test/Frontend/noderef_on_non_pointers.m

// RUN: %clang_cc1 -verify %s

#define NODEREF __attribute__((noderef))

@interface NSObject
+ (id)new;
@end

void func() {
  id NODEREF obj = [NSObject new]; // expected-warning{{'noderef' can only be used on an array or pointer type}}
}