[Qemu-devel] [kvm-unit-tests PATCH] configure: honour $ARCH and $CROSS_COMPILE

[Qemu-devel] [kvm-unit-tests PATCH] configure: honour $ARCH and $CROSS_COMPILE

[Andre Przywara]

Both environment variables seem to be standard in cross-compilation
environments, especially with Linux.
Let the configure script take those into account when setting the default
values for --arch and --cross-prefix. Explicitly specifying the latter
on the configure command line still works as expected.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
---
Hi,

this maybe a personal itch to scratch here, since I set these two
variables in my environment via a (sourced) script here and never have
to care about the particular cross-compiler prefix, for instance.
It looks rather generic, though, so I was wondering if this is useful
upstream as well.

Cheers,
Andre.

 configure | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/configure b/configure
index 995c8fa..9bb38ba 100755
--- a/configure
+++ b/configure
@@ -8,8 +8,9 @@ objdump=objdump
 ar=ar
 addr2line=addr2line
 arch=`uname -m | sed -e 's/i.86/i386/;s/arm.*/arm/;s/ppc64.*/ppc64/'`
+[ -n "$ARCH" ] && arch="$ARCH"
 host=$arch
-cross_prefix=
+cross_prefix=${CROSS_COMPILE}
 endian=""
 pretty_print_stacks=yes
 
-- 
2.9.0

Re: [Qemu-devel] [kvm-unit-tests PATCH] configure: honour $ARCH and $CROSS_COMPILE

[Radim Krčmář]

2016-11-21 18:22+0000, Andre Przywara:
> Both environment variables seem to be standard in cross-compilation
> environments, especially with Linux.
> Let the configure script take those into account when setting the default
> values for --arch and --cross-prefix. Explicitly specifying the latter
> on the configure command line still works as expected.
> 
> Signed-off-by: Andre Przywara <andre.przywara@arm.com>
> ---
> Hi,
> 
> this maybe a personal itch to scratch here, since I set these two
> variables in my environment via a (sourced) script here and never have
> to care about the particular cross-compiler prefix, for instance.
> It looks rather generic, though, so I was wondering if this is useful
> upstream as well.

Definitely useful, thanks.

> diff --git a/configure b/configure
> @@ -8,8 +8,9 @@ objdump=objdump
>  ar=ar
>  addr2line=addr2line
>  arch=`uname -m | sed -e 's/i.86/i386/;s/arm.*/arm/;s/ppc64.*/ppc64/'`
> +[ -n "$ARCH" ] && arch="$ARCH"
>  host=$arch

Host should be set before we override arch, though.

I can swap those two lines when applying, but would prefer something
like:

  host=`uname -m | sed -e 's/i.86/i386/;s/arm.*/arm/;s/ppc64.*/ppc64/'`
  arch=${ARCH:-$host}

> -cross_prefix=
> +cross_prefix=${CROSS_COMPILE}
>  endian=""
>  pretty_print_stacks=yes

(And --help is not printing the default value for cross_prefix, which
 would be nice to change when we can have a non-empty one now.)