[dpdk-dev] [PATCH v3 2/4] build: use dependency() instead of find_library()

[Bruce Richardson]

On Fri, Jan 11, 2019 at 04:26:06PM +0000, Luca Boccassi wrote:
> Whenever possible (if the library ships a pkg-config file) use meson's
> dependency() function to look for it, as it will automatically add it
> to the Requires.private list if needed, to allow for static builds to
> succeed for reverse dependencies of DPDK. Otherwise the recursive
> dependencies are not parsed, and users doing static builds have to
> resolve them manually by themselves.
> When using this API avoid additional checks that are superfluos and

Spelling: superfluous

> take extra time, and avoid adding the linker flag manually which causes
> it to be duplicated.
> 
> Signed-off-by: Luca Boccassi <bluca at debian.org>
> ---
> v2: split libbsd change in a separate commit, remove CC to stable
>     as a meson bump will be required
> 
>  drivers/crypto/ccp/meson.build     | 1 -
>  drivers/crypto/openssl/meson.build | 1 -
>  drivers/crypto/qat/meson.build     | 1 -
>  drivers/meson.build                | 2 +-
>  drivers/net/bnx2x/meson.build      | 2 +-
>  drivers/net/mlx4/meson.build       | 6 +++---
>  drivers/net/mlx5/meson.build       | 6 +++---
>  drivers/net/pcap/meson.build       | 5 ++---
>  lib/librte_bpf/meson.build         | 4 ++--
>  lib/librte_telemetry/meson.build   | 2 +-
>  10 files changed, 13 insertions(+), 17 deletions(-)
> 
> diff --git a/drivers/crypto/ccp/meson.build b/drivers/crypto/ccp/meson.build
> index e43b00591..915c4c854 100644
> --- a/drivers/crypto/ccp/meson.build
> +++ b/drivers/crypto/ccp/meson.build
> @@ -18,4 +18,3 @@ sources = files('rte_ccp_pmd.c',
>  		'ccp_pmd_ops.c')
>  
>  ext_deps += dep
> -pkgconfig_extra_libs += '-lcrypto'
> diff --git a/drivers/crypto/openssl/meson.build b/drivers/crypto/openssl/meson.build
> index c2a0dd8ba..80e5e8835 100644
> --- a/drivers/crypto/openssl/meson.build
> +++ b/drivers/crypto/openssl/meson.build
> @@ -8,4 +8,3 @@ endif
>  deps += 'bus_vdev'
>  sources = files('rte_openssl_pmd.c', 'rte_openssl_pmd_ops.c')
>  ext_deps += dep
> -pkgconfig_extra_libs += '-lcrypto'
> diff --git a/drivers/crypto/qat/meson.build b/drivers/crypto/qat/meson.build
> index 9cc98d2c2..21f969735 100644
> --- a/drivers/crypto/qat/meson.build
> +++ b/drivers/crypto/qat/meson.build
> @@ -13,6 +13,5 @@ if dep.found()
>  			     'qat_sym.c',
>  			     'qat_sym_session.c')
>  	qat_ext_deps += dep
> -	pkgconfig_extra_libs += '-lcrypto'
>  	qat_cflags += '-DBUILD_QAT_SYM'
>  endif
> diff --git a/drivers/meson.build b/drivers/meson.build
> index e37d4fe2b..d17ca76eb 100644
> --- a/drivers/meson.build
> +++ b/drivers/meson.build
> @@ -46,7 +46,7 @@ foreach class:driver_classes
>  		# set up internal deps. Drivers can append/override as necessary
>  		deps = std_deps
>  		# ext_deps: Stores external library dependency got
> -		# using dependency() or cc.find_library(). For most cases, we
> +		# using dependency() (preferred) or find_library(). For most cases, we
>  		# probably also need to specify the "-l" flags in
>  		# pkgconfig_extra_libs variable too, so that it can be reflected
>  		# in the pkgconfig output for static builds

The last part of this comment can now be deleted, right? If we use
dependency() we don't need to use pkgconfig_extra_libs.

Is the pkgconfig_extra_libs variable still needed after these changes?

/Bruce