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 nested8;
extern(C) int printf(char*, ...);

void main()
{
    int i = 1;
    void func()
    {
        printf("func()\n");
        i++;
        void func2()
        {
            printf(" func2()\n");
            int j = i + 1;
            void func3()
            {
                printf("  func3()\n");
                j++;
                printf("  done = %d\n", j);
            }
            func3();
            i = j;
            printf(" done = %d\n", j);
        }
        func2();
        printf("done\n");
    }
    func();
    printf("i == %d\n", i);
    assert(i == 4);
}