Re: [gentoo-dev] [PATCH 1/2] cmake-utils.eclass: Make ninja default backend in EAPI >= 7

[Andreas Sturmlechner <asturm@gentoo.org>]

---Original Message---
On Thursday, 26 July 2018 at 08:35, soap@gentoo.org wrote:

> From: David Seifert <soap@gentoo.org>
> 
> * Using the ninja backend as a default is the only way to
>   massively improve src_compile core utilization, given that
>   it seems unlikely that CMake will ever produce non-recursive
>   Makefiles.
> 
>   For a benchmark, see:
>   http://www.kaizou.org/2016/09/build-benchmark-large-c-project/
> ---
>  eclass/cmake-utils.eclass | 12 +++++++++---
>  1 file changed, 9 insertions(+), 3 deletions(-)
> 
> diff --git a/eclass/cmake-utils.eclass b/eclass/cmake-utils.eclass
> index e64502b3b9b..ed81426ddcc 100644
> --- a/eclass/cmake-utils.eclass
> +++ b/eclass/cmake-utils.eclass
> @@ -53,7 +53,8 @@ _CMAKE_UTILS_ECLASS=1
>  # @DESCRIPTION:
>  # Specify a makefile generator to be used by cmake.
>  # At this point only "emake" and "ninja" are supported.
> -: ${CMAKE_MAKEFILE_GENERATOR:=emake}
> +# In EAPI 7 and above, the default is set to "ninja",
> +# whereas in EAPIs below 7, it is set to "emake".
>  
>  # @ECLASS-VARIABLE: CMAKE_MIN_VERSION
>  # @DESCRIPTION:
> @@ -112,8 +113,13 @@ esac
>  inherit toolchain-funcs ninja-utils flag-o-matic multiprocessing xdg-utils
>  
>  case ${EAPI} in
> -	7) ;;
> -	*) inherit eapi7-ver eutils multilib ;;
> +	[56])
> +		: ${CMAKE_MAKEFILE_GENERATOR:=emake}
> +		inherit eapi7-ver eutils multilib
> +		;;
> +	*)
> +		: ${CMAKE_MAKEFILE_GENERATOR:=ninja}
> +		;;
>  esac
>  
>  EXPORT_FUNCTIONS src_prepare src_configure src_compile src_test src_install
> -- 
> 2.18.0

+1 fwiw, I've been testing this in an overlay branch and it seems to work fine 
so far (no ninja related errors on those packages I rebuilt).