Re: [PATCH v2 2/3] doc: -falign-functions is ignored under -Os

[Eric Gallager <egall@gwmail.gwu.edu>]

On Tue, Oct 11, 2022 at 5:03 PM Palmer Dabbelt <palmer@rivosinc.com> wrote:
>
> This is implicitly mentioned in the docs, but there were some questions
> in a recent patch.  This makes it more exlicit that -falign-functions is
> meant to be ignored under -Os.
>
> gcc/doc/ChangeLog
>
>         * invoke.texi (-falign-functions): Mention -Os

Since there's -Oz now, too, should that be mentioned as well?

> ---
>  gcc/doc/invoke.texi | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
> index 8326a60dcf1..a24798d5029 100644
> --- a/gcc/doc/invoke.texi
> +++ b/gcc/doc/invoke.texi
> @@ -13164,7 +13164,8 @@ equivalent and mean that functions are not aligned.
>  If @var{n} is not specified or is zero, use a machine-dependent default.
>  The maximum allowed @var{n} option value is 65536.
>
> -Enabled at levels @option{-O2}, @option{-O3}.
> +Enabled at levels @option{-O2}, @option{-O3}.  This has no behavior under under
> +@option{-Os}.
>
>  @item -flimit-function-alignment
>  If this option is enabled, the compiler tries to avoid unnecessarily
> --
> 2.34.1
>