1  /* PR preprocessor/89971 */
       2  /* { dg-do compile } */
       3  /* { dg-options "-std=gnu99" { target c } } */
       4  /* { dg-options "-std=c++20" { target c++ } } */
       5  
       6  int a, c;
       7  #define m1(...) a /##__VA_OPT__(b) c
       8  #define m2(...) a /##__VA_OPT__() c
       9  #define m3(...) a##__VA_OPT__()##b = 1
      10  #define m4(...) a##__VA_OPT__(b c d)##e = 2
      11  
      12  int
      13  foo (void)
      14  {
      15    int d = m1();
      16    int e = m2(1);
      17    int m3(1 2 3);
      18    int m4();
      19    return d + e + ab + ae;
      20  }