Now that we're using LLVM 2.5, we can stop always running the CFGSimplification pass. The pass was originally added as a workaround for a LLVM 2.4 bug where debug info would reference labels that have been optimized away.

module structs2;

struct S
{
    int i;
    char c;
    S* s;
    char[4] ca;
}

void main()
{
}