Add extra arg to makeright to allow choice of arm64 or x64 on Darwin (MacOS) platform. Enables cross-compiles bertween x64 and arm64 Macs.

bin/makefile-darwin.aarch64-x

@@ -1,6 +1,6 @@
-# Options for MacOS, x86 processor, X windows
+# Options for MacOS, arm64 (aka aarch64)  processor, X windows
 
-CC = clang $(CLANG_CFLAGS)
+CC = clang  -target arm64-apple-darwin13 $(CLANG_CFLAGS)
 
 XFILES = $(OBJECTDIR)xmkicon.o \
 	$(OBJECTDIR)xbbt.o \

bin/makefile-darwin.x86_64-x

@@ -1,6 +1,6 @@
 # Options for MacOS, x86 processor, X windows
 
-CC = clang -m64 $(CLANG_CFLAGS)
+CC = clang -target x86_64-apple-darwin13 $(CLANG_CFLAGS)
 
 XFILES = $(OBJECTDIR)xmkicon.o \
 	$(OBJECTDIR)xbbt.o \
@@ -26,3 +26,4 @@ LDELDFLAGS =  -L/opt/X11/lib -lX11 -lm
 OBJECTDIR = ../$(RELEASENAME)/
 
 default	: ../$(OSARCHNAME)/lde ../$(OSARCHNAME)/ldex
+

bin/makeright

@@ -54,9 +54,30 @@ if test $# -gt 0
 	shift
 fi
 
+target_arch="$1"
+
+if test $# -gt 0
+    then
+	shift
+fi
+
 architecture=`machinetype`
 osversion=`osversion`
+
+if test "$osversion" != "darwin"
+   then
+       echo "WARNING: target architecture applies only to the Darwin (MacOS) platform":
+       echo "Ignoring target architecture argument: $target"
+elif test "$target_arch" = "x86_64"
+   then
+       architecure=$target_arch
+elif test "$target_arch" = "aarch64"
+   then
+       architecure=$target_arch
+fi
+
 echo "making so far for ${osversion} on ${architecture}."
+
 case "$display" in
 	init)	display=single
 		releasename=init-${osversion}.${architecture}