Regressions on trunk at revision 168160 vs revision 168154

[H.J. Lu ia32]

New failures:
FAIL: gcc.dg/guality/nrv-1.c  -O1  line 20 a2.i[0] == 42
FAIL: gcc.dg/guality/nrv-1.c  -O2  line 20 a2.i[0] == 42
FAIL: gcc.dg/guality/nrv-1.c  -Os  line 20 a2.i[0] == 42

New passes: