[Buildroot] [PATCH] Don't build host-cmake if it is available on the build host

[Arnout Vandecappelle <arnout@mind.be>]

On 01-02-16 22:44, Luca Ceresoli wrote:
> Currently all cmake packages depend on host-cmake. Unfortunately
> host-cmake takes a long time to configure and build: almost 7 minutes
> on a dual-core i5 with SSD. The time does not change even with ccache
> enabled.
> 
> Indeed, building host-ccache is not very useful if it is already

 host-ccache -> host-cmake

> installed on the build host: it is supposed to be quite portable, and
> the only patch we have for cmake seems to only affect target-cmake.
> 
> We avoid building host-cmake if cmake is already available on the host
> using a technique similar to the one used for host-tar and host-xzcat.
> 
> First, we leverage the existing infrastructure in
> support/dependencies/dependencies.mk to set CMAKE to either "cmake" or
> "$(HOST_DIR)/usr/bin/cmake". In the latter case we also set
> BUILD_HOST_CMAKE = YES meaning we need to build host-cmake.
> 
> Then in pkg-cmake.mk we launch $(CMAKE) instead of
> $(HOST_DIR)/usr/bin/cmake.
> 
> Finally, we do skip adding the dependency on host-cmake for all cmake
> packages when $(BUILD_HOST_CMAKE) != YES.
> 
> Unlike what we do for host-tar and host-xzcat, for host-cmake we do
> not add host-cmake to DEPENDENCIES_HOST_PREREQ. Otherwise host-cmake
> would be a dependency for _any_ package when it's not installed on the
> host, even if no cmake package is selected.

 Nice and long commit message, thanks!

> 
> Signed-off-by: Luca Ceresoli <luca@lucaceresoli.net>
> Cc: Samuel Martin <s.martin49@gmail.com>
> Cc: Davide Viti <zinosat@tiscali.it>
> ---
>  package/pkg-cmake.mk                     |  6 ++++--
>  support/dependencies/check-host-cmake.mk |  6 ++++++
>  support/dependencies/check-host-cmake.sh | 14 ++++++++++++++
>  3 files changed, 24 insertions(+), 2 deletions(-)
>  create mode 100644 support/dependencies/check-host-cmake.mk
>  create mode 100755 support/dependencies/check-host-cmake.sh
> 
> diff --git a/package/pkg-cmake.mk b/package/pkg-cmake.mk
> index 81dcfcc..e3bd603 100644
> --- a/package/pkg-cmake.mk
> +++ b/package/pkg-cmake.mk
> @@ -85,7 +85,7 @@ define $(2)_CONFIGURE_CMDS
>  	cd $$($$(PKG)_BUILDDIR) && \
>  	rm -f CMakeCache.txt && \
>  	PATH=$$(BR_PATH) \
> -	$$($$(PKG)_CONF_ENV) $$(HOST_DIR)/usr/bin/cmake $$($$(PKG)_SRCDIR) \
> +	$$($$(PKG)_CONF_ENV) $$(CMAKE) $$($$(PKG)_SRCDIR) \
>  		-DCMAKE_TOOLCHAIN_FILE="$$(HOST_DIR)/usr/share/buildroot/toolchainfile.cmake" \
>  		-DCMAKE_BUILD_TYPE=$$(if $$(BR2_ENABLE_DEBUG),Debug,Release) \
>  		-DCMAKE_INSTALL_PREFIX="/usr" \
> @@ -110,7 +110,7 @@ define $(2)_CONFIGURE_CMDS
>  	cd $$($$(PKG)_BUILDDIR) && \
>  	rm -f CMakeCache.txt && \
>  	PATH=$$(BR_PATH) \
> -	$$(HOST_DIR)/usr/bin/cmake $$($$(PKG)_SRCDIR) \
> +	$$(CMAKE) $$($$(PKG)_SRCDIR) \
>  		-DCMAKE_INSTALL_SO_NO_EXE=0 \
>  		-DCMAKE_FIND_ROOT_PATH="$$(HOST_DIR)" \
>  		-DCMAKE_FIND_ROOT_PATH_MODE_PROGRAM="BOTH" \
> @@ -149,7 +149,9 @@ $(2)_DEPENDENCIES ?= $$(filter-out host-skeleton host-toolchain $(1),\
>  	$$(patsubst host-host-%,host-%,$$(addprefix host-,$$($(3)_DEPENDENCIES))))
>  endif
>  
> +ifeq ($$(BUILD_HOST_CMAKE),YES)
>  $(2)_DEPENDENCIES += host-cmake
> +endif
>  
>  #
>  # Build step. Only define it if not already defined by the package .mk
> diff --git a/support/dependencies/check-host-cmake.mk b/support/dependencies/check-host-cmake.mk
> new file mode 100644
> index 0000000..fe16322
> --- /dev/null
> +++ b/support/dependencies/check-host-cmake.mk
> @@ -0,0 +1,6 @@
> +CMAKE ?= cmake
> +
> +ifeq (,$(call suitable-host-package,cmake,$(CMAKE)))
> +BUILD_HOST_CMAKE = YES
> +CMAKE = $(HOST_DIR)/usr/bin/cmake
> +endif
> diff --git a/support/dependencies/check-host-cmake.sh b/support/dependencies/check-host-cmake.sh
> new file mode 100755
> index 0000000..76a81e0
> --- /dev/null
> +++ b/support/dependencies/check-host-cmake.sh
> @@ -0,0 +1,14 @@
> +#!/bin/sh
> +
> +candidate="$1"
> +
> +cmake=`which $candidate`

 $candidate could be an absolute path, in which case which returns nothing.

> +if [ ! -x "$cmake" ]; then
> +	cmake=`which cmake`

 Since there is already CMAKE ?= cmake in the caller, this is pointless.

 How about a

for cmake in "$cmake" "$( which "$cmake" )"; do
 ...

instead?

> +	if [ ! -x "$cmake" ]; then
> +		# echo nothing: no suitable cmake found
> +		exit 1
> +	fi
> +fi

 I have the feeling that there should also be a version check here, though I
don't know which version we should use.

 Regards,
 Arnout

> +
> +echo $cmake
> 


-- 
Arnout Vandecappelle                          arnout at mind be
Senior Embedded Software Architect            +32-16-286500
Essensium/Mind                                http://www.mind.be
G.Geenslaan 9, 3001 Leuven, Belgium           BE 872 984 063 RPR Leuven
LinkedIn profile: http://www.linkedin.com/in/arnoutvandecappelle
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