gcc/testsuite/gdc.test/fail_compilation/diag11727.d

/*
TEST_OUTPUT:
---
fail_compilation/diag11727.d(10): Error: type `n` is not an expression
---
*/
auto returnEnum()
{
    enum n;
    return n;
}
void main()
{
    assert(returnEnum() == 0);
}

/*
TEST_OUTPUT:
---
fail_compilation/diag11727.d(26): Error: type `void` is not an expression
---
*/
auto returnVoid()
{
    alias v = void;
    return v;
}

/*
TEST_OUTPUT:
---
fail_compilation/diag11727.d(38): Error: template `t()` has no type
---
*/
auto returnTemplate()
{
    template t() {}
    return t;
}