[1/1] package/iperf3: fix build with libatomic

Commit 9f94b3b354 "package/iperf3: bump to version 3.16" updated
the package but forgot to reflect a breaking change mentioned in
the release note [1], "iperf3 now requires pthreads and C atomic
variables to compile and run".

When the toolchain has no atomic support, or the libatomic is not
added in the linker flags, the compilation now fail with output:

    arm-buildroot-linux-gnueabi/bin/ld: ./.libs/libiperf.so: undefined reference to '__atomic_load_8'

This issue can be seen when running the iperf3 runtime test, with
command:

    support/testing/run-tests \
        -d dl -o output_test \
        tests.package.test_iperf3

This commit fixes the issue by adding a dependency on
BR2_TOOLCHAIN_HAS_ATOMIC and by adding an upstream patch to detect
if linking to libatomic is needed.

Fixes: [2]

[1] https://github.com/esnet/iperf/releases/tag/3.16
[2] https://gitlab.com/buildroot.org/buildroot/-/jobs/6466933622

Signed-off-by: Julien Olivain <ju.o@free.fr>
---
 ...1-Check-and-link-libatomic-if-needed.patch | 42 +++++++++++++++++++
 package/iperf3/Config.in                      |  2 +
 package/iperf3/iperf3.mk                      |  3 ++
 3 files changed, 47 insertions(+)
 create mode 100644 package/iperf3/0001-Check-and-link-libatomic-if-needed.patch

Julien, all,

On 2024-04-01 19:16 +0200, Julien Olivain spake thusly:
> Commit 9f94b3b354 "package/iperf3: bump to version 3.16" updated
> the package but forgot to reflect a breaking change mentioned in
> the release note [1], "iperf3 now requires pthreads and C atomic
> variables to compile and run".
> 
> When the toolchain has no atomic support, or the libatomic is not
> added in the linker flags, the compilation now fail with output:
> 
>     arm-buildroot-linux-gnueabi/bin/ld: ./.libs/libiperf.so: undefined reference to '__atomic_load_8'
> 
> This issue can be seen when running the iperf3 runtime test, with
> command:
> 
>     support/testing/run-tests \
>         -d dl -o output_test \
>         tests.package.test_iperf3
> 
> This commit fixes the issue by adding a dependency on
> BR2_TOOLCHAIN_HAS_ATOMIC and by adding an upstream patch to detect
> if linking to libatomic is needed.
> 
> Fixes: [2]
> 
> [1] https://github.com/esnet/iperf/releases/tag/3.16
> [2] https://gitlab.com/buildroot.org/buildroot/-/jobs/6466933622
> 
> Signed-off-by: Julien Olivain <ju.o@free.fr>

Applied to master, thanks.

Regards,
Yann E. MORIN.

> ---
>  ...1-Check-and-link-libatomic-if-needed.patch | 42 +++++++++++++++++++
>  package/iperf3/Config.in                      |  2 +
>  package/iperf3/iperf3.mk                      |  3 ++
>  3 files changed, 47 insertions(+)
>  create mode 100644 package/iperf3/0001-Check-and-link-libatomic-if-needed.patch
> 
> diff --git a/package/iperf3/0001-Check-and-link-libatomic-if-needed.patch b/package/iperf3/0001-Check-and-link-libatomic-if-needed.patch
> new file mode 100644
> index 00000000000..ddb50c46949
> --- /dev/null
> +++ b/package/iperf3/0001-Check-and-link-libatomic-if-needed.patch
> @@ -0,0 +1,42 @@
> +From bbf710e77e4a0438a2d995fd69b472e5ff054c69 Mon Sep 17 00:00:00 2001
> +From: Jan Palus <jpalus@fastmail.com>
> +Date: Sun, 3 Dec 2023 12:14:05 +0100
> +Subject: [PATCH] Check and link libatomic if needed
> +
> +Some architectures without native support for 64-bit atomics need
> +linking with libatomic.
> +
> +Signed-off-by: Julien Olivain <ju.o@free.fr>
> +Upstream: https://github.com/esnet/iperf/commit/1511e9f85b548891ea53d4e378903344df1fd31e
> +---
> + configure.ac | 14 +++++++++++++-
> + 1 file changed, 13 insertions(+), 1 deletion(-)
> +
> +diff --git a/configure.ac b/configure.ac
> +index 2594b39..ad7eaf1 100644
> +--- a/configure.ac
> ++++ b/configure.ac
> +@@ -92,7 +92,19 @@ CXX="$PTHREAD_CXX"
> + ])
> + 
> + # Atomics
> +-AC_CHECK_HEADERS([stdatomic.h])
> ++AC_CHECK_HEADERS([stdatomic.h],
> ++    [AC_MSG_CHECKING([whether libatomic is required])
> ++    AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include <stdatomic.h>]], [[atomic_uint_fast64_t i; i++;]])],
> ++        [AC_MSG_RESULT([no])],
> ++        [save_LIBS="$LIBS"
> ++        LIBS="$LIBS -latomic"
> ++        AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include <stdatomic.h>]], [[atomic_uint_fast64_t i; i++;]])],
> ++            [AC_MSG_RESULT([yes])],
> ++            [AC_MSG_ERROR([failed to find working configuration with atomics])]
> ++        )]
> ++    )],
> ++    []
> ++)
> + 
> + # Check for poll.h (it's in POSIX so everyone should have it?)
> + AC_CHECK_HEADERS([poll.h])
> +-- 
> +2.44.0
> +
> diff --git a/package/iperf3/Config.in b/package/iperf3/Config.in
> index 5b2204c5e01..0c6946f55d9 100644
> --- a/package/iperf3/Config.in
> +++ b/package/iperf3/Config.in
> @@ -1,5 +1,6 @@
>  config BR2_PACKAGE_IPERF3
>  	bool "iperf3"
> +	depends on BR2_TOOLCHAIN_HAS_ATOMIC
>  	depends on BR2_TOOLCHAIN_HAS_THREADS
>  	help
>  	  iperf is a tool for active measurements of the maximum
> @@ -13,4 +14,5 @@ config BR2_PACKAGE_IPERF3
>  	  http://software.es.net/iperf/index.html
>  
>  comment "iperf3 needs a toolchain w/ threads"
> +	depends on BR2_TOOLCHAIN_HAS_ATOMIC
>  	depends on !BR2_TOOLCHAIN_HAS_THREADS
> diff --git a/package/iperf3/iperf3.mk b/package/iperf3/iperf3.mk
> index 6d902c3b13b..3ab68bd13b5 100644
> --- a/package/iperf3/iperf3.mk
> +++ b/package/iperf3/iperf3.mk
> @@ -11,6 +11,9 @@ IPERF3_LICENSE = BSD-3-Clause, BSD-2-Clause, MIT
>  IPERF3_LICENSE_FILES = LICENSE
>  IPERF3_CPE_ID_VENDOR = es
>  
> +# 0001-Check-and-link-libatomic-if-needed.patch
> +IPERF3_AUTORECONF = YES
> +
>  IPERF3_CONF_ENV += CFLAGS="$(TARGET_CFLAGS) -D_GNU_SOURCE"
>  
>  ifeq ($(BR2_PACKAGE_OPENSSL),y)
> -- 
> 2.44.0
> 
> _______________________________________________
> buildroot mailing list
> buildroot@buildroot.org
> https://lists.buildroot.org/mailman/listinfo/buildroot