Re: [Qemu-devel] [PATCH for 2.10 2/4] fdt: check fdt_required condition can be satisfied _after_ testing libfdt

[Michael Roth]

Quoting Philippe Mathieu-Daudé (2017-07-26 16:40:08)
> Signed-off-by: Philippe Mathieu-Daudé <address@hidden>

Previously we failed if fdt_required and the user had built with
--disable-fdt.  For anything other than --disable-fdt, we'd force
the compile check afterward, and then fail if it's not available.

With this patch, we now probe libfdt if --disable-fdt isn't
specified, regardless of whether or not it's required by the
build. It still seems to behave correctly, but I'm not sure
what bug this re-arrangement fixes. Was there some other case
that was missed prior to this patch?

Also, with patch 4 applied on top of this, if they happen to have
a dtc submodule checked out that doesn't build, they will get a
configure error even if they are building a target where where
fdt_required="no".

> ---
>  configure | 18 +++++++++---------
>  1 file changed, 9 insertions(+), 9 deletions(-)
> 
> diff --git a/configure b/configure
> index 063de32773..0d5bdb3ae9 100755
> --- a/configure
> +++ b/configure
> @@ -3558,15 +3558,6 @@ for target in $target_list; do
>    esac
>  done
> 
> -if test "$fdt_required" = "yes"; then
> -  if test "$fdt" = "no"; then
> -    error_exit "fdt disabled but some requested targets require it." \
> -      "You can turn off fdt only if you also disable all the system 
> emulation" \
> -      "targets which need it (by specifying a cut down --target-list)."
> -  fi
> -  fdt=yes
> -fi
> -
>  if test "$fdt" != "no" ; then
>    fdt_libs="-lfdt"
>    # explicitly check for libfdt_env.h as it is missing in some stable 
> installs
> @@ -3603,6 +3594,15 @@ EOF
>    fi
>  fi
> 
> +if test "$fdt_required" = "yes"; then
> +  if test "$fdt" = "no"; then
> +    error_exit "fdt disabled but some requested targets require it." \
> +      "You can turn off fdt only if you also disable all the system 
> emulation" \
> +      "targets which need it (by specifying a cut down --target-list)."
> +  fi
> +  fdt=yes
> +fi
> +
>  libs_softmmu="$libs_softmmu $fdt_libs"
> 
>  ##########################################
> -- 
> 2.13.3
> 
>