Re: [Qemu-devel] [PATCH] Fix cross compilation

[Aurelien Jarno]

On Sun, Apr 11, 2010 at 06:44:18PM +0200, Stefan Weil wrote:
> This patch enhances the algorithm which finds the correct settings for SDL.
> For cross compilations (when cross_prefix is set), it looks for sdl-config
> with cross prefix. Here is the complete search order:
> 
> $(cross_prefix}pkg-config              (old, only used for cross compilation)
> ${cross_prefix}sdl_config              (new, only used for cross compilation)
> pkg-config                             (old, needs PATH)
> sdl-config                             (old, needs PATH)
> 
> Cross SDL packages (or the user) now can simply set a link (for example
> /usr/bin/i586-mingw32msvc-sdl-config -> /usr/i586-mingw32msvc/bin/sdl-config)
> which allows cross compilations without PATH modifications.
> 
> Without the patch, configure and make (which calls configure) typically
> need a non-standard PATH. Failing to set this special PATH results in
> broken builds.
> 
> v2:
> * Favour pkg-config over sdl-config for cross compilations
>   (suggested by Aurelien Jarno) and add comment for this.
> 
> Cc: Aurelien Jarno <address@hidden>
> Signed-off-by: Stefan Weil <address@hidden>
> ---
>  configure |   12 +++++++++++-
>  1 files changed, 11 insertions(+), 1 deletions(-)
> 
> diff --git a/configure b/configure
> index 966cd7d..47fca4f 100755
> --- a/configure
> +++ b/configure
> @@ -1064,7 +1064,17 @@ fi
>  ##########################################
>  # SDL probe
>  
> -if $pkgconfig sdl --modversion >/dev/null 2>&1; then
> +# Look for sdl configuration program (pkg-config or sdl-config).
> +# Prefer variant with cross prefix if cross compiling,
> +# and favour pkg-config with sdl over sdl-config.
> +if test -n "$cross_prefix" -a $pkgconfig != pkg-config && \
                               ^^^^^^^^^^^^^^^^^^^^^^^^^^
                               Why this test ?

> +     $pkgconfig sdl --modversion >/dev/null 2>&1; then
> +  sdlconfig="$pkgconfig sdl"

It should probably be sdlconfig="${cross_prefix}$pkgconfig sdl" so that
the cross version of pkg-config is called later in this file.

> +  _sdlversion=`$sdlconfig --modversion 2>/dev/null | sed 's/[^0-9]//g'`
> +elif test -n "$cross_prefix" && has ${cross_prefix}sdl-config; then
> +  sdlconfig="${cross_prefix}sdl-config"
> +  _sdlversion=`$sdlconfig --version | sed 's/[^0-9]//g'`
> +elif $pkgconfig sdl --modversion >/dev/null 2>&1; then
>    sdlconfig="$pkgconfig sdl"
>    _sdlversion=`$sdlconfig --modversion 2>/dev/null | sed 's/[^0-9]//g'`
>  elif has sdl-config; then
> -- 
> 1.7.0
> 
> 
> 
>