[PATCH libevdev] build: check for build/link flags harder

[David Herrmann]

Hi

On Sun, Nov 17, 2013 at 1:44 PM, Gaetan Nadon <memsize at videotron.ca> wrote:
> From: David Herrmann <dh.herrmann at gmail.com>
>
> Use AC_LINK_IFELSE instead of AC_COMPILE_IFELSE to test for flags that
> might succeed during compilation but not during linking. An example is gcc
> compiled with libssp support but gnu-ld without it. In this case
> -fstack-protector works fine during compilation but fails during linking
> as several internal helpers are missing.
>
> Signed-off-by: Gaetan Nadon <memsize at videotron.ca>
> ---
>
>         Applying maintenance to code obtained from systemd
>         The original patch was not signed-off.

Fine by me:
Signed-off-by: David Herrmann <dh.herrmann at gmail.com>

Thanks!
David

>  m4/attributes.m4 |    6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/m4/attributes.m4 b/m4/attributes.m4
> index 7e080da..aa53ef2 100644
> --- a/m4/attributes.m4
> +++ b/m4/attributes.m4
> @@ -42,9 +42,9 @@ AC_DEFUN([CC_CHECK_FLAG_APPEND], [
>                   AS_TR_SH([cc_cv_$2_$3]),
>            [eval "AS_TR_SH([cc_save_$2])='${$2}'"
>             eval "AS_TR_SH([$2])='-Werror $3'"
> -           AC_COMPILE_IFELSE([AC_LANG_SOURCE([int a = 0; int main(void) { return a; } ])],
> -                                    [eval "AS_TR_SH([cc_cv_$2_$3])='yes'"],
> -                                    [eval "AS_TR_SH([cc_cv_$2_$3])='no'"])
> +           AC_LINK_IFELSE([AC_LANG_SOURCE([int a = 0; int main(void) { return a; } ])],
> +                          [eval "AS_TR_SH([cc_cv_$2_$3])='yes'"],
> +                          [eval "AS_TR_SH([cc_cv_$2_$3])='no'"])
>             eval "AS_TR_SH([$2])='$cc_save_$2'"])
>
>    AS_IF([eval test x$]AS_TR_SH([cc_cv_$2_$3])[ = xyes],
> --
> 1.7.9.5
>