Makefile, swab(1): fixes swab build

Makefile

@@ -133,10 +133,8 @@ build/bin/strcmp: src/strcmp.c build
 
 .PHONY: swab
 swab: build/bin/swab
-build/bin/swab: src/swab.rs build build/o/libsysexits.rlib
-	$(RUSTC) $(RUSTFLAGS) --extern getopt=build/o/libgetopt.rlib \
-		--extern sysexits=build/o/libsysexits.rlib \
-		-o $@ src/swab.rs
+build/bin/swab: src/swab.rs build rustlibs
+	$(RUSTC) $(RUSTFLAGS) $(RUSTLIBS) -o $@ src/swab.rs
 
 .PHONY: true
 true: build/bin/true

src/swab.rs

@@ -53,7 +53,7 @@ fn main() -> ExitCode {
 			Ok("f") => force = true,
 			Ok("w") => {
 				if let Some(arg) = opt.arg() {
-					match opt.arg().parse::<usize>() {
+					match arg.parse::<usize>() {
 						Ok(w) if w % 2 == 0 => { wordsize = w; () },
 						_ => { return usage(&argv[0]); },
 					}