Regressions on trunk at revision 266815 vs revision 266770

[H.J. Lu]

New failures:

New passes:
FAIL: gcc.dg/dfp/fe-binop.c execution test
FAIL: gcc.dg/dfp/fe-binop.c execution test
FAIL: gcc.dg/dfp/fe-binop.c execution test
FAIL: g++.dg/warn/Wstringop-overflow-1.C  -std=c++14 (test for excess errors)
FAIL: g++.dg/warn/Wstringop-overflow-1.C  -std=c++14  (test for warnings, line 14)
FAIL: g++.dg/warn/Wstringop-overflow-1.C  -std=c++17 (test for excess errors)
FAIL: g++.dg/warn/Wstringop-overflow-1.C  -std=c++17  (test for warnings, line 14)
FAIL: g++.dg/warn/Wstringop-overflow-1.C  -std=c++98 (test for excess errors)
FAIL: g++.dg/warn/Wstringop-overflow-1.C  -std=c++98  (test for warnings, line 14)