makefile: add info. Tell how to compile stuff.

makefile

@@ -2,6 +2,14 @@ VERSION ?= 7.3
 ARCH    ?= amd64
 DOMAIN  ?= https://cdn.openbsd.org
 
-all:
+all: create-libc info
+
+create-libc:
 	-mkdir -p $${PWD}/$(VERSION)/$(ARCH)/
 	./build-ziglibc.sh $(DOMAIN)/pub/OpenBSD/$(VERSION)/$(ARCH)/ $${PWD}/$(VERSION)/$(ARCH)/
+
+info:
+	@echo environment variable to use:
+	@echo ZIG_LIBC=$${PWD}/$(VERSION)/$(ARCH)/libc.conf
+	@echo how to compile:
+	@echo zig build -Dtarget=x86_64-openbsd -Doptimize=ReleaseSmall