Check for ldc.conf next to the ldc binary before home and etc. The new search order is * current working directory * next to executable * user home directory * prefix/etc * prefix/etc/ldc * /etc * /etc/ldc

struct Foo { int a, b, c; union Data { } Data data; }
struct Bar { int a, b; }
struct Baz { int a; union { Foo foo; Bar bar; } }
void test() { Baz baz; if (baz.bar.a) return; }