[Buildroot] [PATCH] erlang: selectively enable libatomic_ops

From: Yann E. MORIN <yann.morin.1998@free.fr>
To: buildroot@busybox.net
Subject: [Buildroot] [PATCH] erlang: selectively enable libatomic_ops
Date: Mon, 22 Dec 2014 18:13:04 +0100	[thread overview]
Message-ID: <20141222171304.GA4306@free.fr> (raw)
In-Reply-To: <1419239071-4637-1-git-send-email-fhunleth@troodon-software.com>

Franck, All,

On 2014-12-22 04:04 -0500, Frank Hunleth spake thusly:
> Erlang can use either the system libatomic_ops or its own version.
> However, if using the system version, it must find implementations for
> AO_compare_and_swap() and other calls.  Since these are not available on
> all platforms, selectively enable the use of the system libatomic_ops.
> 
> Fixes:
> http://autobuild.buildroot.net/results/eba/eba5bf85e9ff98916cd3638b5f13ab5bd54564d8/
> http://autobuild.buildroot.net/results/c74/c743cfca629fb332bbb1327cf4ea360f0a4e4bfe/
> http://autobuild.buildroot.net/results/095/095348d4d309c2a408a3b297b4325348ed1dd7e8/
> 
> Signed-off-by: Frank Hunleth <fhunleth@troodon-software.com>
> ---
>  package/erlang/Config.in | 10 ++++++++++
>  package/erlang/erlang.mk |  4 +++-
>  2 files changed, 13 insertions(+), 1 deletion(-)
> 
> diff --git a/package/erlang/Config.in b/package/erlang/Config.in
> index 56830da..9caf1ec 100644
> --- a/package/erlang/Config.in
> +++ b/package/erlang/Config.in
> @@ -26,6 +26,16 @@ config BR2_PACKAGE_ERLANG_SMP
>  	  If you do not need SMP support, turning this option off reduces
>  	  compile time and the size of the Erlang installation.
>  
> +config BR2_PACKAGE_ERLANG_USE_LIBATOMIC_OPS
> +	bool
> +	select BR2_PACKAGE_LIBATOMIC_OPS
> +	default y if BR2_ARM_CPU_ARMV7A || BR2_x86_64

Well, we already have BR2_PACKAGE_LIBATOMIC_ARCH_SUPPORTS that defines
which architecture libatomic_ops supports.

So, unless AO_compare_and_swap() is not available on all those
architectures (and it seems it is), you should use that symbol instead.

> +	help
> +	  Use the system libatomic_ops on platforms that provide
> +	  implementations for AO_store(), AO_load(), and AO_compare_and_swap().
> +	  Platforms without support for those functions must still use the
> +	  Erlang-provided implementation.
> +
>  config BR2_PACKAGE_ERLANG_MEGACO
>  	bool "install megaco application"
>  	help
> diff --git a/package/erlang/erlang.mk b/package/erlang/erlang.mk
> index 0b8619e..007053a 100644
> --- a/package/erlang/erlang.mk
> +++ b/package/erlang/erlang.mk
> @@ -22,9 +22,11 @@ ERLANG_CONF_ENV += erl_xcomp_sysroot=$(STAGING_DIR)
>  
>  ERLANG_CONF_OPTS = --without-javac
>  
> -ifeq ($(BR2_PACKAGE_LIBATOMIC_OPS),y)
> +ifeq ($(BR2_PACKAGE_ERLANG_USE_LIBATOMIC_OPS),y)
>  ERLANG_DEPENDENCIES += libatomic_ops
>  ERLANG_CONF_OPTS += --with-libatomic_ops=$(STAGING_DIR)/usr
> +else
> +ERLANG_CONF_OPTS += --without-libatomic_ops
>  endif

So the consition for this block should stay the same, but the
--without-libatomic_ops addition is still welcome.

Regards,
Yann E. MORIN.

>  # erlang uses openssl for all things crypto. Since the host tools (such as
> -- 
> 1.9.1
> 
> _______________________________________________
> buildroot mailing list
> buildroot at busybox.net
> http://lists.busybox.net/mailman/listinfo/buildroot

-- 
.-----------------.--------------------.------------------.--------------------.
|  Yann E. MORIN  | Real-Time Embedded | /"\ ASCII RIBBON | Erics' conspiracy: |
| +33 662 376 056 | Software  Designer | \ / CAMPAIGN     |  ___               |
| +33 223 225 172 `------------.-------:  X  AGAINST      |  \e/  There is no  |
| http://ymorin.is-a-geek.org/ | _/*\_ | / \ HTML MAIL    |   v   conspiracy.  |
'------------------------------^-------^------------------^--------------------'