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digitalmars.D.learn - CTFE cannot be used when a struct has "uninitialized" static array

reply "simendsjo" <simendsjo gmail.com> writes:
This is probably not a minimal test-case, and I haven't tested 
with more types, but it shows the problem.

// This works
struct S {
     this(int i) {
         a = i;
     }
     union {
         int a = void;
         int b = void;
     }
}
unittest
{
     auto s = S(1);
     assert(&s.a == &s.b);
     enum s2 = S(1);
     static assert(S(1).a == 1);
}

// But this doesn't
struct S2 {
     this(int i) { // error at this line
         a[] = i;
     }
     union {
         int[1] a = void;
         int[1] b = void;
     }
}
unittest
{
     auto s = S2(1);
     assert(s.a.ptr == s.b.ptr);
     // bug.d(19): Error: uninitialized variable 'b' cannot be 
returned from CTFE
     enum s2 = S2(1);
}

void main() {
}
Apr 14 2013
parent "simendsjo" <simendsjo gmail.com> writes:
Filed a bug. http://d.puremagic.com/issues/show_bug.cgi?id=9932
Apr 14 2013