Makefile

@@ -18,21 +18,17 @@ PREFIX ?= /usr/local
 
 MANDIR != [ $(PREFIX) = / ] && printf '/usr/share/man\n' \
 	|| printf '/share/man\n'
-SYSEXITS != printf '\043include <sysexits.h>\n' | cpp -M - | sed 's/ /\n/g' \
-	| sed -n 's/sysexits\.h//p' || printf 'include\n'
 
 CC ?= cc
 RUSTC ?= rustc
 RUSTLIBS = --extern getopt=build/o/libgetopt.rlib \
 	--extern sysexits=build/o/libsysexits.rlib \
 	--extern strerror=build/o/libstrerror.rlib
-CFLAGS += -I$(SYSEXITS)
+CFLAGS += -Ibuild/include
 
 .PHONY: all
 all: docs dj false fop hru intcmp mm npc rpn scrut str strcmp swab true
 
-# keep build/include until bindgen(1) has stdin support
-# https://github.com/rust-lang/rust-bindgen/issues/2703
 build:
 	mkdir -p build/bin build/docs build/include build/lib build/o build/test
 
@@ -65,6 +61,12 @@ docs: docs/ build
 rustlibs: build/o/libsysexits.rlib build/o/libgetopt.rlib \
 	build/o/libstrerror.rlib
 
+build/include/sysexits.h: build include/sysexits.h.template
+	cpp -dM -include sysexits.h /dev/null \
+			| grep '^.define EX_' >$@ \
+		|| cpp -dM -include stdlib.h include/sysexits.h.template \
+			| grep -e '^.define EX_' -e '^.define EXIT_' >$@
+
 build/o/libgetopt.rlib: build src/getopt-rs/lib.rs
 	$(RUSTC) $(RUSTFLAGS) --crate-type=lib --crate-name=getopt \
 		-o $@ src/getopt-rs/lib.rs