Re: [dpdk-dev] [PATCH 3/6] net/mlx: fix library search in meson build

[Luca Boccassi <bluca@debian.org>]

On Fri, 2019-04-12 at 16:24 -0700, Yongseok Koh wrote:
> If MLNX_OFED is installed, there's no .pc file installed for
> libraries and
> dependency() can't find libraries by pkg-config. By adding fallback
> of
> using cc.find_library(), libraries are properly located.
> 
> Fixes: e30b4e566f47 ("build: improve dependency handling")
> Cc: 
> bluca@debian.org
> 
> Cc: 
> stable@dpdk.org
> 
> 
> Signed-off-by: Yongseok Koh <
> yskoh@mellanox.com
> >
> ---
>  drivers/net/mlx4/meson.build | 19 +++++++++++--------
>  drivers/net/mlx5/meson.build | 19 +++++++++++--------
>  2 files changed, 22 insertions(+), 16 deletions(-)
> 
> diff --git a/drivers/net/mlx4/meson.build
> b/drivers/net/mlx4/meson.build
> index de020701d1..9082f69f25 100644
> --- a/drivers/net/mlx4/meson.build
> +++ b/drivers/net/mlx4/meson.build
> @@ -13,21 +13,24 @@ if pmd_dlopen
>  		'-DMLX4_GLUE_VERSION="@0@"'.format(LIB_GLUE_VERSION),
>  	]
>  endif
> -libs = [
> -	dependency('libmnl', required:false),
> -	dependency('libmlx4', required:false),
> -	dependency('libibverbs', required:false),
> -]
> +libs = [ 'libmnl', 'libmlx4', 'libibverbs' ]
> +lib_deps = []
>  build = true
>  foreach lib:libs
> -	if not lib.found()
> +	lib_dep = dependency(lib, required:false)
> +	if not lib_dep.found()
> +		lib_dep = cc.find_library(lib, required:false)

Doesn't this end up trying to link the test program to -llibmnl and
thus failing?

> +	endif
> +	if lib_dep.found()
> +		lib_deps += [ lib_dep ]
> +	else
>  		build = false
>  	endif
>  endforeach
>  # Compile PMD
>  if build
>  	allow_experimental_apis = true
> -	ext_deps += libs
> +	ext_deps += lib_deps
>  	sources = files(
>  		'mlx4.c',
>  		'mlx4_ethdev.c',
> @@ -103,7 +106,7 @@ if pmd_dlopen and build
>  		dlopen_sources,
>  		include_directories: global_inc,
>  		c_args: cflags,
> -		dependencies: libs,
> +		dependencies: libs_deps,
>  		link_args: [
>  		'-Wl,-export-dynamic',
>  		'-Wl,-h,@0@'.format(LIB_GLUE),

-- 
Kind regards,
Luca Boccassi