// https://issues.dlang.org/show_bug.cgi?id=23778 enum __c_long_double : double; alias __c_long_double c_long_double; struct _Complex { c_long_double re; c_long_double im; } version (all) // bug to test { enum __c_complex_real : _Complex; alias c_complex_real = __c_complex_real; } else // works enum c_complex_real : _Complex; c_complex_real toNative2(real re, real im) { return c_complex_real(re, im); } void main() { c_complex_real n = toNative2(123, 456); assert(123 == n.re && 456 == n.im); }