Regressions on trunk at revision 245986 vs revision 245970

[H.J. Lu]

New failures:

New passes:
FAIL: g++.dg/Walloca1.C  -std=gnu++11 (test for excess errors)
FAIL: g++.dg/Walloca1.C  -std=gnu++11  (test for warnings, line 6)
FAIL: g++.dg/Walloca1.C  -std=gnu++14 (test for excess errors)
FAIL: g++.dg/Walloca1.C  -std=gnu++14  (test for warnings, line 6)
FAIL: g++.dg/Walloca1.C  -std=gnu++98 (test for excess errors)
FAIL: g++.dg/Walloca1.C  -std=gnu++98  (test for warnings, line 6)