Richard, here's some fall-out from your tree-sra rewrite
  http://gcc.gnu.org/ml/gcc-cvs/2004-06/msg01253.html
The following code snippet crashes mainline when compiled with optimization:

============================================
struct A
{
    void (A::*p)();
    void foo() const { (A().*p)(); }
};

inline A makeA() { return A(); }

void bar()
{
    makeA().foo();
}
============================================

The error message is:

bug.cc: In function `void bar()':
bug.cc:10: internal compiler error: in generate_element_copy, at tree-sra.c:1461
Please submit a full bug report, [etc.]