gcc/testsuite/gdc.test/compilable/test12807.d

   1 void foo(T)(ref T t)
   2 {
   3 }
   4
   5 struct S
   6 {
   7     int impure() {assert(0);}
   8     alias impure this;
   9 }
  10
  11 void main() pure
  12 {
  13     S s;
  14     foo(s);
  15     s.foo(); // triggering alias this violates purity, but ufcs matches
  16 }