Call configure automatically when needed

Automatically rerun configure when it is needed.
Signed-off-by: NStefan Weil <weil@mail.berlios.de>
Signed-off-by: NAurelien Jarno <aurelien@aurel32.net>

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7110 c046a42c-6fe2-441c-8c8c-71466251a162

Makefile

 # Makefile for QEMU.
 
+ifneq ($(wildcard config-host.mak),)
 include config-host.mak
 include $(SRC_PATH)/rules.mak
+else
+config-host.mak:
+	@echo "Please call configure before running make!"
+	@exit 1
+endif
 
 .PHONY: all clean cscope distclean dvi html info install install-doc \
 	recurse-all speed tar tarbin test
@@ -36,6 +42,12 @@ endif
 
 all: $(TOOLS) $(DOCS) recurse-all
 
+config-host.mak: configure
+ifneq ($(wildcard config-host.mak),)
+	@echo $@ is out-of-date, running configure
+	@fgrep "Configured with:" $@ | sed s/.*Configured.with:.// | sh
+endif
+
 SUBDIR_RULES=$(patsubst %,subdir-%, $(TARGET_DIRS))
 
 subdir-%: