Make Makefile.ukvm safe to use with BSD make, sort of

mato · mato · commit 27d53c19f908 · 2017-04-05T12:18:20.000+02:00
This is a temporary solution to avoid having to teach MirageOS about
"which make to use". It is not expected to work for including
Makefile.ukvm from other makefiles.
diff --git a/ukvm/ukvm-configure b/ukvm/ukvm-configure
@@ -114,6 +114,11 @@ cat <<EOF> Makefile.ukvm
 # Generated by 'ukvm-configure $@'
 # Using compiler '${UKVM_CC}', target '${TARGET}'
 
+.BEGIN: ; @echo -e Warning: \$(MAKEFILE) requires GNU make.\\\\nWarning: Attempting to build with \"gmake -f \$(MAKEFILE) \$(.TARGETS)\" for you now. && gmake -f \$(MAKEFILE) \$(.TARGETS)
+
+.PHONY: all
+all: ukvm-bin
+
 UKVM_CC=${UKVM_CC}
 UKVM_CFLAGS=-Wall -Werror -std=c99 -O2 -g ${UKVM_CFLAGS}
 UKVM_LDFLAGS=${UKVM_LDFLAGS}
@@ -135,6 +140,6 @@ ukvm-bin: \$(UKVM_OBJS) \$(MAKEFILE_LIST)
 
 .PHONY: ukvm-clean
 ukvm-clean:
-	\$(RM) -r _build-ukvm
-	\$(RM) ukvm-bin
+	rm -rf _build-ukvm
+	rm -f ukvm-bin
 EOF
