Regressions on 4.5 at revision 160424 vs revision 160417

[H.J. Lu ia64]

New failures:
FAIL: 25_algorithms/stable_sort/mem_check.cc (test for excess errors)
FAIL: g++.dg/torture/pr36826.C  -O3 -g  (test for excess errors)
FAIL: gcc.c-torture/compile/20030405-1.c  -O3 -fomit-frame-pointer -funroll-loops  (test for excess errors)

New passes:
FAIL: 29_atomics/atomic_integral/cons/copy_list.cc (test for excess errors)
FAIL: gcc.c-torture/compile/limits-blockid.c  -O3 -g  (test for excess errors)
FAIL: gcc.c-torture/execute/pr30778.c compilation,  -O2 -flto