C++ test-case regression

[Mark Mitchell]

There's been a recent regression on g++.mike/net16.C, enclosed below.
Compile on x86-linux-gnu with no flags; the compiler crashes in
change_stack.  I'm trying to track down the change that caused the bug
now.  

Attached is the test-case.

--
Mark Mitchell                   mark@codesourcery.com
CodeSourcery, LLC               http://www.codesourcery.com

extern "C" int printf (const char*, ...);
struct S { ~S () { } };
double f (S) { return 5; } 
int main() { S s; double dist = f (s); printf ("%g\n", dist); return 0; }