diff --git a/qemu/configure b/qemu/configure
index 1da64d52..87b8d5cf 100755
--- a/qemu/configure
+++ b/qemu/configure
@@ -178,6 +178,9 @@ tcg="yes"
 cpuid_h="no"
 avx2_opt="no"
 
+supported_cpu="no"
+supported_os="no"
+
 # parse CC options first
 for opt do
   optarg=$(expr "x$opt" : 'x[^=]*=\(.*\)')
@@ -356,23 +359,32 @@ ARCH=
 # Normalise host CPU name and set ARCH.
 # Note that this case should only have supported host CPUs, not guests.
 case "$cpu" in
-  ppc|ppc64|s390|s390x|sparc64|x32)
+  ppc|ppc64|s390|s390x|x32)
+    cpu="$cpu"
+    supported_cpu="yes"
+  ;;
+  sparc64)
     cpu="$cpu"
   ;;
   i386|i486|i586|i686|i86pc|BePC)
     cpu="i386"
+    supported_cpu="yes"
   ;;
   x86_64|amd64)
     cpu="x86_64"
+    supported_cpu="yes"
   ;;
   armv*b|armv*l|arm)
     cpu="arm"
+    supported_cpu="yes"
   ;;
   aarch64|aarch64eb)
     cpu="aarch64"
+    supported_cpu="yes"
   ;;
   mips*)
     cpu="mips"
+    supported_cpu="yes"
   ;;
   sparc|sun4[cdmuv])
     cpu="sparc"
@@ -391,6 +403,7 @@ fi
 case $targetos in
 MINGW32*)
   mingw32="yes"
+  supported_os="yes"
 ;;
 GNU/kFreeBSD)
   bsd="yes"
@@ -400,6 +413,7 @@ FreeBSD)
   make="${MAKE-gmake}"
   # needed for kinfo_getvmmap(3) in libutil.h
   LIBS="-lutil $LIBS"
+  supported_os="yes"
 ;;
 DragonFly)
   bsd="yes"
@@ -424,6 +438,7 @@ Darwin)
   # Disable attempts to use ObjectiveC features in os/object.h since they
   # won't work when we're compiling with gcc as a C compiler.
   QEMU_CFLAGS="-DOS_OBJECT_USE_OBJC=0 $QEMU_CFLAGS"
+  supported_os="yes"
 ;;
 SunOS)
   solaris="yes"
@@ -442,8 +457,12 @@ Haiku)
   QEMU_CFLAGS="-DB_USE_POSITIVE_POSIX_ERRORS $QEMU_CFLAGS"
   LIBS="-lposix_error_mapper -lnetwork $LIBS"
 ;;
-*)
+Linux)
   linux="yes"
+  supported_os="yes"
+;;
+*)
+  error_exit "Unsupported host OS $targetos"
 ;;
 esac
 
@@ -1288,6 +1307,32 @@ if test "$tcg" = "yes" ; then
 fi
 echo "avx2 optimization $avx2_opt"
 
+if test "$supported_cpu" = "no"; then
+    echo
+    echo "WARNING: SUPPORT FOR THIS HOST CPU WILL GO AWAY IN FUTURE RELEASES!"
+    echo
+    echo "CPU host architecture $cpu support is not currently maintained."
+    echo "The QEMU project intends to remove support for this host CPU in"
+    echo "a future release if nobody volunteers to maintain it and to"
+    echo "provide a build host for our continuous integration setup."
+    echo "configure has succeeded and you can continue to build, but"
+    echo "if you care about QEMU on this platform you should contact"
+    echo "us upstream at qemu-devel@nongnu.org."
+fi
+
+if test "$supported_os" = "no"; then
+    echo
+    echo "WARNING: SUPPORT FOR THIS HOST OS WILL GO AWAY IN FUTURE RELEASES!"
+    echo
+    echo "CPU host OS $targetos support is not currently maintained."
+    echo "The QEMU project intends to remove support for this host CPU in"
+    echo "a future release if nobody volunteers to maintain it and to"
+    echo "provide a build host for our continuous integration setup."
+    echo "configure has succeeded and you can continue to build, but"
+    echo "if you care about QEMU on this platform you should contact"
+    echo "us upstream at qemu-devel@nongnu.org."
+fi
+
 config_host_mak="config-host.mak"
 
 echo "# Automatically generated by configure - do not modify" > $config_host_mak