Regressions on trunk at revision 250377 vs revision 250336

[H.J. Lu]

New failures:
FAIL: gcc.dg/tree-prof/merge_block.c scan-tree-dump-times optimized "__builtin_memchr" 2

New passes:
FAIL: 21_strings/basic_string/modifiers/insert/char/1.cc execution test
FAIL: 21_strings/basic_string/modifiers/insert/char/1.cc execution test
FAIL: 21_strings/basic_string/modifiers/insert/wchar_t/1.cc execution test
FAIL: 21_strings/basic_string/modifiers/insert/wchar_t/1.cc execution test
FAIL: g++.dg/debug/debug9.C -gstabs+1 -O2 (test for excess errors)
FAIL: g++.dg/debug/debug9.C -gstabs+1 -O2 (test for excess errors)
FAIL: g++.dg/debug/debug9.C -gstabs1 -O2 (test for excess errors)
FAIL: g++.dg/debug/debug9.C -gstabs1 -O2 (test for excess errors)
FAIL: g++.dg/debug/debug9.C -gstabs+1 -O3 (test for excess errors)
FAIL: g++.dg/debug/debug9.C -gstabs+1 -O3 (test for excess errors)
FAIL: g++.dg/debug/debug9.C -gstabs1 -O3 (test for excess errors)
FAIL: g++.dg/debug/debug9.C -gstabs1 -O3 (test for excess errors)
FAIL: g++.dg/debug/debug9.C -gstabs+3 -O2 (test for excess errors)
FAIL: g++.dg/debug/debug9.C -gstabs3 -O2 (test for excess errors)
FAIL: g++.dg/debug/debug9.C -gstabs+3 -O3 (test for excess errors)
FAIL: g++.dg/debug/debug9.C -gstabs3 -O3 (test for excess errors)
FAIL: g++.dg/debug/debug9.C -gstabs -O2 (test for excess errors)
FAIL: g++.dg/debug/debug9.C -gstabs+ -O2 (test for excess errors)
FAIL: g++.dg/debug/debug9.C -gstabs -O3 (test for excess errors)
FAIL: g++.dg/debug/debug9.C -gstabs+ -O3 (test for excess errors)