llvm-project/clang/test/CodeGenCXX/default-arg-temps.cpp

// RUN: %clang_cc1 -emit-llvm %s -o %t -triple=x86_64-apple-darwin9

struct T {
  T();
  ~T();
};

void f(const T& t = T());

class X { // ...
public:
        X();
        X(const X&, const T& t = T());
};

void g() {
  // RUN: grep "call void @_ZN1TC1Ev" %t | count 4
  // RUN: grep "call void @_ZN1TD1Ev" %t | count 4
  f();
  f();

  X a;
  X b(a);
  X c = a;
}


// RUN: grep memset %t
class obj{ int a; float b; double d; };
void h() {
  obj o = obj();
}