gcc/testsuite/gdc.test/fail_compilation/diag2452.d

/*
TEST_OUTPUT:
---
fail_compilation/diag2452.d(14): Error: class diag2452.C interface function 'void f(float p)' is not implemented
---
*/

interface I
{
    void f(int p);
    void f(float p);
}

class C : I
{
    void f(int p) { }
}