[Buildroot] [PATCH v2, 1/1] package/mbuffer: fix build with c89 or c99

[Yann E. MORIN <yann.morin.1998@free.fr>]

Fabrice. All,

On 2020-04-21 17:24 +0200, Fabrice Fontaine spake thusly:
> Fixes:
>  - http://autobuild.buildroot.org/results/5f4e9079b3377a869ec7002a8138b80eb6194bbb
> 
> Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
> ---
> Changes v1 -> v2 (after review of Thomas Petazzoni):
>  - Define _POSIX_SOURCE instead of including linux/limits.h
> 
>  ...gure.in-set-AC_USE_SYSTEM_EXTENSIONS.patch | 38 +++++++++++++++++++
>  package/mbuffer/mbuffer.mk                    |  2 +
>  2 files changed, 40 insertions(+)
>  create mode 100644 package/mbuffer/0002-configure.in-set-AC_USE_SYSTEM_EXTENSIONS.patch
> 
> diff --git a/package/mbuffer/0002-configure.in-set-AC_USE_SYSTEM_EXTENSIONS.patch b/package/mbuffer/0002-configure.in-set-AC_USE_SYSTEM_EXTENSIONS.patch
> new file mode 100644
> index 0000000000..f116bd575a
> --- /dev/null
> +++ b/package/mbuffer/0002-configure.in-set-AC_USE_SYSTEM_EXTENSIONS.patch
> @@ -0,0 +1,38 @@
> +From 1f2a7e575b3594ef02aae85eee8d1feac0c08266 Mon Sep 17 00:00:00 2001
> +From: Fabrice Fontaine <fontaine.fabrice@gmail.com>
> +Date: Tue, 21 Apr 2020 14:30:20 +0200
> +Subject: [PATCH] configure.in: set AC_USE_SYSTEM_EXTENSIONS
> +
> +Set AC_USE_SYSTEM_EXTENSIONS so _POSIX_SOURCE will be defined and the
> +following build failure will be avoided when building in c89 or c99
> +mode:
> +
> +log.c: In function 'infomsg':
> +log.c:123:12: error: 'PIPE_BUF' undeclared (first use in this function)
> +   if (s <= PIPE_BUF) {
> +            ^~~~~~~~
> +
> +Fixes:
> + - http://autobuild.buildroot.org/results/5f4e9079b3377a869ec7002a8138b80eb6194bbb
> +
> +Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
> +[Upstream status: sent to thomas at maier-komor.de]
> +---
> + configure.in | 1 +
> + 1 file changed, 1 insertion(+)
> +
> +diff --git a/configure.in b/configure.in
> +index 02921c2..078373c 100644
> +--- a/configure.in
> ++++ b/configure.in
> +@@ -30,6 +30,7 @@ AC_PROG_CC_C99
> + AC_PROG_CC(cc gcc)
> + AC_C_RESTRICT
> + AC_C_INLINE
> ++AC_USE_SYSTEM_EXTENSIONS

As per the documentation, AC_USE_SYSTEM_EXTENSIONS must be used before
any macros that run the compiler, and I believe AC_C_RESTRICT and
AC_C_INLINE both do.

Regards,
Yann E. MORIN.

> + if test "${USRCFLAGS}" = "" ; then
> + 	if test "${GCC}" = "yes" ; then
> +-- 
> +2.25.1
> +
> diff --git a/package/mbuffer/mbuffer.mk b/package/mbuffer/mbuffer.mk
> index 6ff6e27a39..324780fe69 100644
> --- a/package/mbuffer/mbuffer.mk
> +++ b/package/mbuffer/mbuffer.mk
> @@ -11,6 +11,8 @@ MBUFFER_LICENSE = GPL-3.0+
>  MBUFFER_LICENSE_FILES = LICENSE
>  MBUFFER_CONF_OPTS = --disable-debug
>  MBUFFER_CONF_ENV = CFLAGS="$(TARGET_CFLAGS) -std=c99"
> +# We're patching configure.in
> +MBUFFER_AUTORECONF = YES
>  
>  # we don't need tests & co. so we specify a target
>  # so that the others don't get built, e.g idev.so
> -- 
> 2.25.1
> 
> _______________________________________________
> 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     |  ___               |
| +33 561 099 427 `------------.-------:  X  AGAINST      |  \e/  There is no  |
| http://ymorin.is-a-geek.org/ | _/*\_ | / \ HTML MAIL    |   v   conspiracy.  |
'------------------------------^-------^------------------^--------------------'