Another shot at fixing the issues with (constant) struct literals and their addresses. See DMD2682, #218, #324. The idea is to separate the notion of const from 'this variable can always be replaced with its initializer' in the frontend. To do that, I introduced Declaration::isSameAsInitializer, which is overridden in VarDeclaration to return false for constants that have a struct literal initializer. So {{{ const S s = S(5); void foo() { auto ps = &s; } // is no longer replaced by void foo() { auto ps = &(S(5)); } }}} To make taking the address of a struct constant with a struct-initializer outside of function scope possible, I made sure that AddrExp::optimize doesn't try to run the argument's optimization with WANTinterpret - that'd again replace the constant with a struct literal temporary.

module aa6;

extern(C) int printf(char*, ...);

void main()
{
    int[int] aa;
    aa = [1:1, 2:4, 3:9, 4:16];
    printf("---\n");
    foreach(int k, int v; aa)
        printf("aa[%d] = %d\n", k, v);
    aa.rehash;
    printf("---\n");
    foreach(int k, int v; aa)
        printf("aa[%d] = %d\n", k, v);
    size_t n = aa.length;
    assert(n == 4);
    int[] keys = aa.keys;
    assert(keys[] == [1,2,3,4][]);
    int[] vals = aa.values;
    assert(vals[] == [1,4,9,16][]);
    aa.remove(3);
    printf("---\n");
    foreach(int k, int v; aa)
        printf("aa[%d] = %d\n", k, v);
    assert(aa.length == 3);
}