Regressions on trunk at revision 272505 vs revision 272468

[H.J. Lu (Intel64)]

New failures:

New passes:
FAIL: g++.dg/ubsan/pr63956.C   -O0  (test for excess errors)
FAIL: g++.dg/ubsan/pr63956.C   -O0  (test for excess errors)
FAIL: g++.dg/ubsan/pr63956.C   -O1  (test for excess errors)
FAIL: g++.dg/ubsan/pr63956.C   -O1  (test for excess errors)
FAIL: g++.dg/ubsan/pr63956.C   -O2 -flto -fno-use-linker-plugin -flto-partition=none  (test for excess errors)
FAIL: g++.dg/ubsan/pr63956.C   -O2 -flto -fno-use-linker-plugin -flto-partition=none  (test for excess errors)
FAIL: g++.dg/ubsan/pr63956.C   -O2 -flto -fuse-linker-plugin -fno-fat-lto-objects  (test for excess errors)
FAIL: g++.dg/ubsan/pr63956.C   -O2 -flto -fuse-linker-plugin -fno-fat-lto-objects  (test for excess errors)
FAIL: g++.dg/ubsan/pr63956.C   -O2  (test for excess errors)
FAIL: g++.dg/ubsan/pr63956.C   -O2  (test for excess errors)
FAIL: g++.dg/ubsan/pr63956.C   -O3 -g  (test for excess errors)
FAIL: g++.dg/ubsan/pr63956.C   -O3 -g  (test for excess errors)
FAIL: g++.dg/ubsan/pr63956.C   -Os  (test for excess errors)
FAIL: g++.dg/ubsan/pr63956.C   -Os  (test for excess errors)