[Buildroot] [PATCH 1/2] meson: fix malformed cross-compilation.conf.in

[Thomas Petazzoni <thomas.petazzoni@free-electrons.com>]

Hello,

On Fri, 29 Dec 2017 16:52:42 -0500, Adam Duskett wrote:
> Currently, meson will set the c_link_args and the cpp_link_args to the value
> of TARGET_LDFLAGS, even when it's not defined.
> 
> This creates a malformed array ["",] which will break any package building
> using meson/ninja.
> 
> Add a small regular expression at the end of the sed command to check for
> ["", ] and replace it with [] instead.
> 
> Credit goes to Yann for the regular expression.
> 
> Signed-off-by: Adam Duskett <Adamduskett@outlook.com>
> ---
>  package/meson/meson.mk | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/package/meson/meson.mk b/package/meson/meson.mk
> index 55ce84da07..75b9a1666a 100644
> --- a/package/meson/meson.mk
> +++ b/package/meson/meson.mk
> @@ -26,6 +26,7 @@ define HOST_MESON_INSTALL_CROSS_CONF
>  	    -e "s%@TARGET_LDFLAGS@%`printf '"%s", ' $(TARGET_LDFLAGS)`%g" \
>  	    -e "s%@TARGET_CXXFLAGS@%`printf '"%s", ' $(TARGET_CXXFLAGS)`%g" \
>  	    -e "s%@HOST_DIR@%$(HOST_DIR)%g" \
> +	    -e 's/\["", \]/[]/' \
>  	    $(HOST_MESON_PKGDIR)/cross-compilation.conf.in \
>  	    > $(HOST_DIR)/etc/meson/cross-compilation.conf  
>  endef

While this works, it feels a bit like a hack to me: we are just fixing
the mess we have created a few lines before. Can we instead do the
replacement only if it's needed ? Or calculate some intermediate
variable that is empty is TARGET_CFLAGS is empty, and equal to
'"$(TARGET_CFLAGS)", ' if not ?

Thomas
-- 
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com