Regressions on trunk at revision 257517 vs revision 257478

[H.J. Lu Intel64 Core i7]

New failures:
FAIL: g++.dg/vect/slp-pr56812.cc  -std=c++11  (test for warnings, line 17)
FAIL: g++.dg/vect/slp-pr56812.cc  -std=c++11  (test for warnings, line 17)
FAIL: g++.dg/vect/slp-pr56812.cc  -std=c++14  (test for warnings, line 17)
FAIL: g++.dg/vect/slp-pr56812.cc  -std=c++14  (test for warnings, line 17)
FAIL: g++.dg/vect/slp-pr56812.cc  -std=c++98  (test for warnings, line 17)
FAIL: g++.dg/vect/slp-pr56812.cc  -std=c++98  (test for warnings, line 17)

New passes:
FAIL: gcc.dg/tree-ssa/ssa-dom-cse-2.c scan-tree-dump optimized "return 28;"
FAIL: gcc.dg/tree-ssa/ssa-dom-cse-2.c scan-tree-dump optimized "return 28;"
FAIL: gcc.target/i386/mvc9.c (test for excess errors)
FAIL: gcc.target/i386/mvc9.c (test for excess errors)
FAIL: g++.dg/torture/pr67600.C   -O2 -flto -fuse-linker-plugin -fno-fat-lto-objects  (test for excess errors)
FAIL: g++.dg/torture/pr67600.C   -O2 -flto -fuse-linker-plugin -fno-fat-lto-objects  (test for excess errors)
FAIL: g++.dg/vect/slp-pr56812.cc  -std=c++11  scan-tree-dump-times slp1 "basic block vectorized" 1 (found 0 times)
FAIL: g++.dg/vect/slp-pr56812.cc  -std=c++11  scan-tree-dump-times slp1 "basic block vectorized" 1 (found 0 times)
FAIL: g++.dg/vect/slp-pr56812.cc  -std=c++14  scan-tree-dump-times slp1 "basic block vectorized" 1 (found 0 times)
FAIL: g++.dg/vect/slp-pr56812.cc  -std=c++14  scan-tree-dump-times slp1 "basic block vectorized" 1 (found 0 times)
FAIL: g++.dg/vect/slp-pr56812.cc  -std=c++98  scan-tree-dump-times slp1 "basic block vectorized" 1 (found 0 times)
FAIL: g++.dg/vect/slp-pr56812.cc  -std=c++98  scan-tree-dump-times slp1 "basic block vectorized" 1 (found 0 times)