Hi. I'm going to install the patch that suppresses -O0 warning:
../../gcc/combine.c: In function ‘rtx_code simplify_compare_const(rtx_code, machine_mode, rtx, rtx_def**)’: ../../gcc/combine.c:11789:7: warning: this statement may fall through [-Wimplicit-fallthrough=] if (const_op > 0) ^~ ../../gcc/combine.c:11808:5: note: here case LEU: ^~~~ ../../gcc/combine.c:11826:7: warning: this statement may fall through [-Wimplicit-fallthrough=] if (const_op > 1) ^~ ../../gcc/combine.c:11846:5: note: here case GTU: ^~~~ Martin gcc/ChangeLog: 2017-10-18 Martin Liska <mli...@suse.cz> * combine.c (simplify_compare_const): Add gcc_fallthrough. --- gcc/combine.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/gcc/combine.c b/gcc/combine.c index 3b96d86bdb3..757ae6fc93e 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -11791,6 +11791,7 @@ simplify_compare_const (enum rtx_code code, machine_mode mode, const_op -= 1; code = LEU; /* ... fall through ... */ + gcc_fallthrough (); } /* (unsigned) < 0x80000000 is equivalent to >= 0. */ else if (is_a <scalar_int_mode> (mode, &int_mode) @@ -11828,6 +11829,7 @@ simplify_compare_const (enum rtx_code code, machine_mode mode, const_op -= 1; code = GTU; /* ... fall through ... */ + gcc_fallthrough (); } /* (unsigned) >= 0x80000000 is equivalent to < 0. */