https://cgit.freebsd.org/ports/tree/devel/wasi-libc/Makefile#n40
avoid rebuilding everything in fake

Index: Makefile
--- Makefile.orig
+++ Makefile
@@ -565,7 +565,7 @@ check-symbols: startup_files libc
 	# This ignores whitespace because on Windows the output has CRLF line endings.
 	diff -wur "$(CURDIR)/expected/$(MULTIARCH_TRIPLE)" "$(SYSROOT_SHARE)"
 
-install: finish
+install:
 	mkdir -p "$(INSTALL_DIR)"
 	cp -r "$(SYSROOT)/lib" "$(SYSROOT)/share" "$(SYSROOT)/include" "$(INSTALL_DIR)"
 
