[Qemu-devel] [PATCH RFC] configure: shorthand for only enabling native softmmu target

["Daniel P. Berrangé" <berrange@redhat.com>]

With the huge number of QEMU targets, a default configuration will take
a very long time to rebuild. When developing most code changes, it is
sufficient to test compilation with a single target - rebuilding all
targets just extends compile times while not detecting any new problems.

Developers will often thus specify a single target for configure,
commonly matching the host architecture. eg

  ./configure --target-list=x86_64-softmmu

This works fine, but is a bit of a verbose thing to type out everytime
configure is invoked. There are already short-hand args to disable all
user targets, all softmmu targets, or all tcg targets. This adds one
further shorthand to disable all non-native architecture targets.

  ./configure --native

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---

Suggestions welcomed for better names than --native, but bear in mind
the goal is to minimise amount of typing so nothing too verbose, hence
why I didn't do something like --disable-non-native ...

 configure | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/configure b/configure
index af72fc852e..807af93116 100755
--- a/configure
+++ b/configure
@@ -233,6 +233,22 @@ supported_whpx_target() {
     return 1
 }
 
+supported_native_target() {
+    glob "$1" "*-softmmu" || return 1
+    case "${1%-softmmu}:$cpu" in
+        arm:arm | aarch64:aarch64 | \
+        i386:i386 | i386:x32 | \
+        x86_64:x86_64 | \
+        mips:mips | mipsel:mips | \
+        ppc:ppc | ppcemb:ppc | \
+        ppc64:ppc64 | \
+        s390x:s390x)
+            return 0
+        ;;
+    esac
+    return 1
+}
+
 supported_target() {
     case "$1" in
         *-softmmu)
@@ -254,6 +270,10 @@ supported_target() {
             return 1
             ;;
     esac
+    if test "$native" = "yes"
+    then
+	supported_native_target "$1" || return 1
+    fi
     test "$tcg" = "yes" && return 0
     supported_kvm_target "$1" && return 0
     supported_xen_target "$1" && return 0
@@ -390,6 +410,7 @@ cocoa="no"
 softmmu="yes"
 linux_user="no"
 bsd_user="no"
+native="no"
 blobs="yes"
 pkgversion=""
 pie=""
@@ -1112,6 +1133,8 @@ for opt do
       cocoa="yes" ;
       audio_drv_list="coreaudio $(echo $audio_drv_list | sed s,coreaudio,,g)"
   ;;
+  --native) native="yes"
+  ;;
   --disable-system) softmmu="no"
   ;;
   --enable-system) softmmu="yes"
@@ -1540,6 +1563,7 @@ Advanced options (experts only):
                            xen pv domain builder
   --enable-debug-stack-usage
                            track the maximum stack usage of stacks created by qemu_alloc_stack
+  --native                 only enable the softmmu target matching host architecture
 
 Optional features, enabled with --enable-FEATURE and
 disabled with --disable-FEATURE, default is enabled if available:
-- 
2.14.3