Regressions on trunk at revision 220551 vs revision 220544

[H.J. Lu Intel64 Core i7]

New failures:
FAIL: c-c++-common/torture/builtin-arith-overflow-12.c   -O2 -flto -fuse-linker-plugin -fno-fat-lto-objects  execution test
FAIL: c-c++-common/torture/builtin-arith-overflow-12.c   -O2 -flto -fuse-linker-plugin -fno-fat-lto-objects  execution test
FAIL: c-c++-common/torture/builtin-arith-overflow-13.c   -O2 -flto -fuse-linker-plugin -fno-fat-lto-objects  execution test
FAIL: c-c++-common/torture/builtin-arith-overflow-13.c   -O2 -flto -fuse-linker-plugin -fno-fat-lto-objects  execution test
FAIL: c-c++-common/torture/builtin-arith-overflow-14.c   -O2 -flto -fuse-linker-plugin -fno-fat-lto-objects  execution test
FAIL: c-c++-common/torture/builtin-arith-overflow-14.c   -O2 -flto -fuse-linker-plugin -fno-fat-lto-objects  execution test
FAIL: c-c++-common/torture/builtin-arith-overflow-15.c   -O2 -flto -fuse-linker-plugin -fno-fat-lto-objects  execution test
FAIL: c-c++-common/torture/builtin-arith-overflow-15.c   -O2 -flto -fuse-linker-plugin -fno-fat-lto-objects  execution test
FAIL: c-c++-common/torture/builtin-arith-overflow-16.c   -O2 -flto -fuse-linker-plugin -fno-fat-lto-objects  execution test
FAIL: c-c++-common/torture/builtin-arith-overflow-16.c   -O2 -flto -fuse-linker-plugin -fno-fat-lto-objects  execution test
FAIL: gcc.dg/guality/pr43177.c   -O2 -flto -fuse-linker-plugin -fno-fat-lto-objects  line 15 l == 10
FAIL: gcc.dg/guality/pr43177.c   -O2 -flto -fuse-linker-plugin -fno-fat-lto-objects  line 15 x == 7

New passes: