Regressions on trunk at revision 267609 vs revision 267606

[H.J. Lu (Intel64 Core i7)]

New failures:

New passes:
FAIL: c-c++-common/attributes-4.c  -std=gnu++14 (test for excess errors)
FAIL: c-c++-common/attributes-4.c  -std=gnu++17 (test for excess errors)
FAIL: c-c++-common/attributes-4.c  -std=gnu++98 (test for excess errors)
FAIL: c-c++-common/attributes-4.c  -Wc++-compat  (test for excess errors)