Regressions on trunk at revision 266233 vs revision 266175

[H.J. Lu (Intel64)]

New failures:
FAIL: gcc.dg/Wbuiltin-declaration-mismatch-4.c (test for excess errors)
FAIL: gcc.dg/Wbuiltin-declaration-mismatch-4.c  (test for warnings, line 80)
FAIL: gcc.dg/Wbuiltin-declaration-mismatch-4.c  (test for warnings, line 82)

New passes:
FAIL: gcc.target/i386/pr80173.c (internal compiler error)
FAIL: gcc.target/i386/pr80173.c (test for excess errors)