configure: --enable-racket=auto to simplify cross-compilation

Using `--enable-racket=auto` causes a Racket for the current platform
to be built in a "local" subdirectory of the build directory as
support for cross-compilation.

racket/src/Makefile.in

@@ -54,6 +54,7 @@ TAGS:
 	etags `find "@srcdir@/racket" -type f`
 
 3m:
+	$(MAKE) @MAKE_LOCAL_RACKET@
 	cd racket; $(MAKE) 3m
 	$(MAKE) @MAKE_GRACKET@-3m
 
@@ -64,6 +65,7 @@ no-3m:
 	$(NOOP)
 
 cgc:
+	$(MAKE) @MAKE_LOCAL_RACKET@
 	cd racket; $(MAKE) cgc
 	$(MAKE) @MAKE_GRACKET@-cgc
 
@@ -77,6 +79,19 @@ both:
 	$(MAKE) cgc
 	$(MAKE) 3m
 
+# Cross-compilation helper:
+
+no-local-racket:
+	$(NOOP)
+
+local/racket/racket3m:
+	mkdir -p local
+	$(MAKE) local/Makefile
+	cd local ; $(MAKE)
+
+local/Makefile:
+	cd local ; `cd ..; cd $(srcdir); pwd`/configure --disable-gracket
+
 # Install (common) ----------------------------------------
 
 INST_CONFIG = -X @DIRCVTPRE@"$(DESTDIR)$(collectsdir)"@DIRCVTPOST@ -G @DIRCVTPRE@"$(DESTDIR)$(configdir)"@DIRCVTPOST@

racket/src/README

@@ -271,11 +271,16 @@ Cross-compilation requires at least two flags to `configure':
    such as `OS-gcc' and `OS-strip'.
 
  * `--enable-racket=RACKET', where RACKET is a path to a Racket
-   executable for the version being compiled that runs on the build
+   executable that runs on the build platform; the executable must be
-   platform.
+   the same version of Racket as being built for the target platform.
 
    This flag is needed because building and installing Racket requires
-   running (an intermediate version of) Racket.
+   running (an existing build of) Racket.
+
+   Use "auto" for RACKET to indicates that one should be built
+   automatically for the current platform. In that case, `make`
+   will run `configure` again (with no arguments) in a "local"
+   subdirectory to create a build for the current platform.
 
 Some less commonly needed `configure' flags:
 
@@ -292,7 +297,7 @@ the NDK, use (all on one line)
 
   configure --host=arm-linux-androideabi 
             --enable-sysroot="[ndk]/platforms/android-[N]/arch-arm"
-            --enable-racket=racket
+            --enable-racket=auto
 
 where [ndk] is the path to the installed NDK, [N] is a target version
 of Android (such as 14), and

racket/src/configure

@@ -624,6 +624,7 @@ enable_option_checking=no
 ac_subst_vars='LTLIBOBJS
 LIBOBJS
 subdirs
+MAKE_LOCAL_RACKET
 CGC_IF_NEEDED_FOR_MMM
 RUN_RACKET_MAIN_VARIANT
 RUN_RACKET_MMM
@@ -1441,7 +1442,7 @@ Optional Features:
   --enable-float          support single-precision floats (enabled by default)
   --enable-floatinstead   use single-precision by default (NOT RECOMMENDED)
   --enable-extflonum      support extflonums (enabled by default, if available)
-  --enable-racket=<path>  use <path> as Racket executable to build Racket
+  --enable-racket=<path>  use <path> as Racket to build; or "auto" to create
   --enable-origtree       install with original directory structure
   --enable-pkgscope=<s>   set `raco pkg' default: installation, user, or shared
   --enable-docs           build docs on install (enabled by default)
@@ -3096,7 +3097,11 @@ if test "${enable_sysroot}" != "" ; then
 fi
 
 if test "${enable_racket}" != "" ; then
-   echo "=== Using Racket executable ${enable_racket}"
+  if test "${enable_racket}" == "auto" ; then
+     echo "=== Creating and using local Racket executable"
+  else
+     echo "=== Using Racket executable ${enable_racket}"
+  fi
 fi
 
 INSTALL_PKGSCOPE=user
@@ -3180,6 +3185,8 @@ use_flag_posix_pthread=no
 skip_iconv_check=no
 check_page_size=yes
 
+MAKE_LOCAL_RACKET=no-local-racket
+
 ###### OSKit stuff #######
 
 if test "${enable_oskit}" = "yes" ; then
@@ -6646,6 +6653,11 @@ fi
 
 ############## Racket for Racket ################
 
+if test "${enable_racket}" = "auto" ; then
+  enable_racket="`pwd`/local/racket/racket3m"
+  MAKE_LOCAL_RACKET="local/racket/racket3m"
+fi
+
 if test "${enable_racket}" = "" ; then
   RUN_RACKET_CGC='$(RUN_THIS_RACKET_CGC)'
   RUN_RACKET_MMM='$(RUN_THIS_RACKET_MMM)'
@@ -6852,6 +6864,8 @@ LIBS="$LIBS $EXTRALIBS"
 
 
 
+
+
 
 
 

racket/src/racket/configure.ac

@@ -41,7 +41,7 @@ AC_ARG_ENABLE(float,   [  --enable-float          support single-precision float
 AC_ARG_ENABLE(floatinstead, [  --enable-floatinstead   use single-precision by default (NOT RECOMMENDED)])
 AC_ARG_ENABLE(extflonum,    [  --enable-extflonum      support extflonums (enabled by default, if available)], , enable_extflonum=default)
 
-AC_ARG_ENABLE(racket,  [  --enable-racket=<path>  use <path> as Racket executable to build Racket])
+AC_ARG_ENABLE(racket,  [  --enable-racket=<path>  use <path> as Racket to build; or "auto" to create])
 
 AC_ARG_ENABLE(origtree,[  --enable-origtree       install with original directory structure])
 AC_ARG_ENABLE(pkgscope,[  --enable-pkgscope=<s>   set `raco pkg' default: installation, user, or shared])
@@ -368,7 +368,11 @@ if test "${enable_sysroot}" != "" ; then
 fi
 
 if test "${enable_racket}" != "" ; then
-   echo "=== Using Racket executable ${enable_racket}"
+  if test "${enable_racket}" == "auto" ; then
+     echo "=== Creating and using local Racket executable"
+  else
+     echo "=== Using Racket executable ${enable_racket}"
+  fi 
 fi
 
 INSTALL_PKGSCOPE=user
@@ -452,6 +456,8 @@ use_flag_posix_pthread=no
 skip_iconv_check=no
 check_page_size=yes
 
+MAKE_LOCAL_RACKET=no-local-racket
+
 ###### OSKit stuff #######
 
 if test "${enable_oskit}" = "yes" ; then
@@ -1561,6 +1567,11 @@ fi
 
 ############## Racket for Racket ################
 
+if test "${enable_racket}" = "auto" ; then
+  enable_racket="`pwd`/local/racket/racket3m"
+  MAKE_LOCAL_RACKET="local/racket/racket3m"
+fi
+
 if test "${enable_racket}" = "" ; then
   RUN_RACKET_CGC='$(RUN_THIS_RACKET_CGC)'
   RUN_RACKET_MMM='$(RUN_THIS_RACKET_MMM)'
@@ -1770,6 +1781,8 @@ AC_SUBST(RUN_RACKET_MMM)
 AC_SUBST(RUN_RACKET_MAIN_VARIANT)
 AC_SUBST(CGC_IF_NEEDED_FOR_MMM)
 
+AC_SUBST(MAKE_LOCAL_RACKET)
+
 mk_needed_dir()
 {
   if test ! -d "$1" ; then