Chez Scheme: add "auto.bootquick" makefile target

The "auto.bootquick" target maps to "<machine type.bootquick" for
whatever machine type would be inferred by `configure`.

racket/src/ChezScheme/BUILDING

@@ -46,26 +46,33 @@ VIA SHELL section later in this file. Otherwise, to get further
 instructions, try running
 
   ./configure
-  make <machine type>
+  make
 
-The output will either suggest using Racket as
-
-  racket rktboot/main.rkt --machine <machine type>
-
-or using the pb boot files with
+The output will either suggest using using the pb boot files with
 
   ./configure --pb
   make <machine type>.bootquick
 
-and then trying again with `./configure`.
+or Racket as
 
-If you plan to build on multiple different machines, then it may be a
-good idea to generate pb boot files via Racket:
+  racket rktboot/main.rkt --machine <machine type>
+
+and then trying again with `./configure`. In the former case, you can
+use "auto.bootquick" instead of "<machine type>.bootquick".
+
+If you plan to build on multiple different machines and you don't have
+pbb bboot files, then it may be a good idea to generate pb boot files
+via Racket:
 
   racket rktboot/main.rkt --machine pb
 
-Then, you can use the ob boot files on different machines instead of
-having to install Racket on each machine.
+Then, you can use the pb boot files on different machines instead of
+having to install Racket on each machine. Alternatively, after you
+have a Chez Scheme build on one machine, you can use use
+
+  make <machine type>.boot
+
+to more quickly create boot files for any <machine type>.
 
 
 CONFIGURING AND BUILDING

racket/src/ChezScheme/README.md

@@ -3,6 +3,16 @@ that language, with supporting tools and documentation.
 This variant of Chez Scheme is extended to support the implementation
 of [Racket](https://racket-lang.org/).
 
+Supported platforms:
+
+ * Windows: x86, x86_64
+ * Mac OS: x86, x86_64, PowerPC32
+ * Linux: x86, x86_64, ARMv6, AArch64, PowerPC32
+ * FreeBSD: x86, x86_64
+ * OpenBSD: x86, x86_64
+ * NetBSD: x86, x86_64
+ * Solaris: x86, x86_64
+
 As a superset of the language described in the
 [Revised<sup>6</sup> Report on the Algorithmic Language Scheme](http://www.r6rs.org)
 (R6RS), Chez Scheme supports all standard features of Scheme,

racket/src/ChezScheme/configure

@@ -367,6 +367,12 @@ if [ "$threads" = "" ] ; then
   threads=yes
 fi
 
+if [ $bits = 64 ] ; then
+  if [ $threads = yes ] ; then defaultm=$tm64 ; else defaultm=$m64 ; fi
+else
+  if [ $threads = yes ] ; then defaultm=$tm32 ; else defaultm=$m32 ; fi
+fi
+
 if [ "$m" = "" ] ; then
   machine_supplied=no
   if [ $pb = yes ] ; then
@@ -374,11 +380,7 @@ if [ "$m" = "" ] ; then
      if [ $bits = 64 ] ; then mpbhost=$m64 ; else mpbhost=$m32 ; fi
      flagsm=$mpbhost
   else      
-    if [ $bits = 64 ] ; then
-      if [ $threads = yes ] ; then m=$tm64 ; else m=$m64 ; fi
-    else
-      if [ $threads = yes ] ; then m=$tm32 ; else m=$m32 ; fi
-    fi
+    m=$defaultm
     flagsm=$m
   fi
 elif [ $pb = yes ] ; then
@@ -672,6 +674,7 @@ esac
 "$srcdir"/workarea $m $w $mpbhost
 
 sed -e 's/$(m)/'$m'/g'\
+    -e 's/$(defaultm)/'$defaultm'/g'\
     -e 's/$(workarea)/'$w'/g'\
   "$srcdir"/makefiles/Makefile.in > Makefile
 
@@ -687,6 +690,7 @@ sed -e 's/$(m)/'$m'/g'\
 cat "$srcdir"/makefiles/Makefile-workarea.in > $w/Makefile
 
 sed -e 's/$(m)/'$m'/g'\
+    -e 's/$(m)/'$m'/g'\
     -e 's/$(workarea)/'$w'/g'\
     "$srcdir"/makefiles/Mf-boot.in > $w/Mf-boot
 

racket/src/ChezScheme/makefiles/Makefile.in

@@ -57,6 +57,9 @@ reset:
 %.bootquick:
 	(cd $(workarea) && $(MAKE) $*.bootquick)
 
+auto.bootquick:
+	(cd $(workarea) && $(MAKE) $(defaultm).bootquick)
+
 # Supply ORIG=<dir> to build using existing at <dir>
 .PHONY: from-orig
 from-orig: