Regressions on trunk at revision 167437 vs revision 167425

[H.J. Lu Intel64-profiled]

New failures:
FAIL: gcc.dg/guality/pr43479.c  -O2 -flto  line 13 h == 9

New passes:
FAIL: 20_util/unique_ptr/requirements/explicit_instantiation/explicit_instantiation.cc (test for excess errors)
FAIL: 20_util/unique_ptr/requirements/explicit_instantiation/explicit_instantiation.cc (test for excess errors)
FAIL: gcc.dg/guality/pr43479.c  -O2 -flto  line 18 h == 9
FAIL: gcc.dg/guality/vla-2.c  -O3 -fomit-frame-pointer  line 25 sizeof (a) == 6 * sizeof (int)