Tested on x86_64.
> -----Original Message-----
> From: Gcc-patches <gcc-patches-boun...@gcc.gnu.org> On Behalf Of Hu
> Jiangping
> Sent: Monday, July 27, 2020 3:46 PM
> To: gcc-patches@gcc.gnu.org; richard.sandif...@arm.com;
> seg...@kernel.crashing.org
> Subject: [PATCH v3] driver: fix a problem with implementation of -falign-foo=0
> [PR96247]
>
> Hi!
>
> This patch makes the -falign-foo=0 work as described in the
> documentation. Thanks for all the suggestions, Richard and Segher!
>
> v3: make change more readable and self-consistent
> v2: at a high level handles -falign-foo=0 like -falign-foo
>
> Regards!
> Hujp
>
> ---
> gcc/opts.c | 24 +++++++++++++++++++-----
> 1 file changed, 19 insertions(+), 5 deletions(-)
>
> diff --git a/gcc/opts.c b/gcc/opts.c
> index 499eb900643..dec5ba6d2be 100644
> --- a/gcc/opts.c
> +++ b/gcc/opts.c
> @@ -2007,10 +2007,20 @@ parse_and_check_align_values (const char *flag,
> location LOC. */
>
> static void
> -check_alignment_argument (location_t loc, const char *flag, const char
> *name)
> +check_alignment_argument (location_t loc,
> + const char *flag,
> + const char *name,
> + int *opt_flag,
> + const char **opt_str)
> {
> auto_vec<unsigned> align_result;
> parse_and_check_align_values (flag, name, align_result, true, loc);
> +
> + if (align_result.length() >= 1 && align_result[0] == 0)
> + {
> + *opt_flag = 1;
> + *opt_str = NULL;
> + }
> }
>
> /* Print help when OPT__help_ is set. */
> @@ -2785,19 +2795,23 @@ common_handle_option (struct gcc_options
> *opts,
> break;
>
> case OPT_falign_loops_:
> - check_alignment_argument (loc, arg, "loops");
> + check_alignment_argument (loc, arg, "loops",
> + &opts->x_flag_align_loops, &opts->x_str_align_loops);
> break;
>
> case OPT_falign_jumps_:
> - check_alignment_argument (loc, arg, "jumps");
> + check_alignment_argument (loc, arg, "jumps",
> + &opts->x_flag_align_jumps, &opts->x_str_align_jumps);
> break;
>
> case OPT_falign_labels_:
> - check_alignment_argument (loc, arg, "labels");
> + check_alignment_argument (loc, arg, "labels",
> + &opts->x_flag_align_labels, &opts->x_str_align_labels);
> break;
>
> case OPT_falign_functions_:
> - check_alignment_argument (loc, arg, "functions");
> + check_alignment_argument (loc, arg, "functions",
> + &opts->x_flag_align_functions, &opts->x_str_align_functions);
> break;
>
> case OPT_ftabstop_:
> --
> 2.17.1
>
>
