Clean up build process for cross-compiled targets.

  * Over time, the process for producing an SBCL build for another
target architecture or OS has become more difficult and less
documented.

  * Move all make.sh argument processing to make-config.sh.

  * Have make-config.sh produce a file, output/build-config,
containing shell commands to set up important build parameters
such as where to find GNUMAKE, what SBCL_XC_HOST is, and so on.

  * Source output/build-config in most of the make*.sh scripts.

  * The practical upshot of all this is that a cross-compile
build is now a matter of alternating between target and host,
calling make-config.sh, make-host-1.sh, make-target-1.sh,
make-host-2.sh, make-target-2.sh, and following up with a
make-target-contrib.sh on the target, and you wind up with a
usable product.  And, as make-config.sh does all of the arg
parsing, you can pass --xc-host= or --dynamic-space-size= or
whatever and it all works out.

make-config.sh

@@ -17,6 +17,187 @@ set -e
 # provided with absolutely no warranty. See the COPYING and CREDITS
 # files for more information.
 
+print_help="no"
+
+# The classic form here was to use --userinit $DEVNULL --sysinit
+# $DEVNULL, but that doesn't work on Win32 because SBCL doesn't handle
+# device names properly. We still need $DEVNULL to be NUL on Win32
+# because it's used elsewhere (such as canonicalize-whitespace), so we
+# need an alternate solution for the init file overrides. --no-foos
+# have now been available long enough that this should not stop anyone
+# from building.
+if [ "$OSTYPE" = "cygwin" -o "$OSTYPE" = "msys" ]
+then
+    SBCL_PREFIX="$PROGRAMFILES/sbcl"
+else
+    SBCL_PREFIX="/usr/local"
+fi
+SBCL_XC_HOST="sbcl --disable-debugger --no-userinit --no-sysinit"
+export SBCL_XC_HOST
+
+# Parse command-line options.
+bad_option() {
+    echo $1
+    echo "Enter \"$0 --help\" for list of valid options."
+    exit 1
+}
+
+some_options=false
+for option
+do
+  optarg_ok=true
+  # Split --foo=bar into --foo and bar.
+  case $option in
+      *=*)
+        # For ease of scripting treat skip valued options with empty
+        # values.
+        optarg=`expr "X$option" : '[^=]*=\(.*\)'` || optarg_ok=false
+        option=`expr "X$option" : 'X\([^=]*=\).*'`
+        ;;
+      *)
+        optarg=""
+        ;;
+  esac
+
+  case $option in
+      --help | -help | -h)
+        print_help="yes" ;;
+      --prefix=)
+        $optarg_ok && SBCL_PREFIX=$optarg
+        ;;
+      --xc-host=)
+        $optarg_ok && SBCL_XC_HOST=$optarg
+        ;;
+      --dynamic-space-size=)
+        $optarg_ok && SBCL_DYNAMIC_SPACE_SIZE=$optarg
+	;;
+      -*)
+        bad_option "Unknown command-line option to $0: \"$option\""
+        ;;
+      *)
+        if $some_options
+        then
+            bad_option "Unknown command-line option to $0: \"$option\""
+        else
+            legacy_xc_spec=$option
+        fi
+        ;;
+  esac
+  some_options=true
+done
+
+# Previously XC host was provided as a positional argument. 
+if test -n "$legacy_xc_spec"
+then
+    SBCL_XC_HOST="$legacy_xc_spec"
+fi
+
+if test "$print_help" = "yes"
+then
+  cat <<EOF
+\`make.sh' drives the SBCL build.
+
+Usage: $0 [OPTION]...
+
+  Important: make.sh does not currently control the entirety of the
+  build: configuration file customize-target-features.lisp and certain
+  environment variables play a role as well. see file INSTALL for
+  details.
+
+Options:
+  -h, --help           Display this help and exit.
+
+  --prefix=<path>      Specify the install location.
+
+      Script install.sh installs SBCL under the specified prefix
+      path: runtime as prefix/bin/sbcl, additional files under
+      prefix/lib/sbcl, and documentation under prefix/share.
+
+      This option also affects the binaries: built-in default for
+      SBCL_HOME is: prefix/lib/sbcl/
+
+      Default prefix is: /usr/local
+
+  --dynamic-space-size=<size> Default dynamic-space size for target.
+
+      This specifies the default dynamic-space size for the SBCL
+      being built. If you need to control the dynamic-space size
+      of the host SBCL, use the --xc-host option.
+
+      If not provided, the default is platform-specific. <size> is
+      taken to be megabytes unless explicitly suffixed with Gb in
+      order to specify the size in gigabytes.
+
+  --xc-host=<string>   Specify the Common Lisp compilation host.
+
+      The string provided should be a command to invoke the
+      cross-compilation Lisp system in such a way, that it reads
+      commands from standard input, and terminates when it reaches end
+      of file on standard input.
+
+      Examples:
+
+       "sbcl --disable-debugger --no-sysinit --no-userinit"
+                  Use an existing SBCL binary as a cross-compilation
+                  host even though you have stuff in your
+                  initialization files which makes it behave in such a
+                  non-standard way that it keeps the build from
+                  working. Also disable the debugger instead of
+                  waiting endlessly for a programmer to help it out
+                  with input on *DEBUG-IO*. (This is the default.)
+
+       "sbcl"
+                  Use an existing SBCL binary as a cross-compilation
+                  host, including your initialization files and
+                  building with the debugger enabled. Not recommended
+                  for casual users.
+
+       "lisp -noinit -batch"
+                  Use an existing CMU CL binary as a cross-compilation
+                  host when you have weird things in your .cmucl-init
+                  file.
+EOF
+  exit 1
+fi
+
+mkdir -p output
+# Save prefix for make and install.sh.
+echo "SBCL_PREFIX='$SBCL_PREFIX'" > output/prefix.def
+echo "$SBCL_DYNAMIC_SPACE_SIZE" > output/dynamic-space-size.txt
+
+# FIXME: Tweak this script, and the rest of the system, to support
+# a second bootstrapping pass in which the cross-compilation host is
+# known to be SBCL itself, so that the cross-compiler can do some
+# optimizations (especially specializable arrays) that it doesn't
+# know how to implement how in a portable way. (Or maybe that wouldn't
+# require a second pass, just testing at build-the-cross-compiler time
+# whether the cross-compilation host returns suitable values from
+# UPGRADED-ARRAY-ELEMENT-TYPE?)
+
+if [ "$OSTYPE" = "cygwin" -o "$OSTYPE" = "msys" ] ; then
+    DEVNULL=NUL
+else
+    DEVNULL=/dev/null
+fi
+export DEVNULL
+
+. ./find-gnumake.sh
+find_gnumake
+
+. ./generate-version.sh
+generate_version
+
+# Now that we've done our option parsing and found various
+# dependencies, write them out to a file to be sourced by other
+# scripts.
+
+echo "export DEVNULL=\"$DEVNULL\"" > output/build-config
+echo "export GNUMAKE=\"$GNUMAKE\"" >> output/build-config
+echo "export SBCL_XC_HOST=\"$SBCL_XC_HOST\"" >> output/build-config
+echo "export legacy_xc_spec=\"$legacy_xc_spec\"" >> output/build-config
+
+# And now, sorting out the per-target dependencies...
+
 case `uname` in
     Linux)
         sbcl_os="linux"

make-host-1.sh

@@ -20,6 +20,9 @@ LANG=C
 LC_ALL=C
 export LANG LC_ALL
 
+# Load our build configuration
+. output/build-config
+
 # Compile and load the cross-compiler. (We load it here not because we're
 # about to use it, but because it's written under the assumption that each
 # file will be loaded before the following file is compiled.)

make-host-2.sh

@@ -20,6 +20,9 @@ LANG=C
 LC_ALL=C
 export LANG LC_ALL
 
+# Load our build configuration
+. output/build-config
+
 # In some cases, a debugging build of the system will creates a core
 # file output/after-xc.core in the next step. In cases where it
 # doesn't, it's confusing and basically useless to have any old copies

make-target-1.sh

@@ -20,6 +20,9 @@ LANG=C
 LC_ALL=C
 export LANG LC_ALL
 
+# Load our build configuration
+. output/build-config
+
 # Build the runtime system and symbol table (.nm) file.
 #
 # (This C build has to come after the first genesis in order to get

make-target-2.sh

@@ -20,6 +20,9 @@ LANG=C
 LC_ALL=C
 export LANG LC_ALL
 
+# Load our build configuration
+. output/build-config
+
 # Do warm init stuff, e.g. building and loading CLOS, and stuff which
 # can't be done until CLOS is running.
 #

make-target-contrib.sh

@@ -20,8 +20,8 @@ LANG=C
 LC_ALL=C
 export LANG LC_ALL
 
-. ./find-gnumake.sh
-find_gnumake
+# Load our build configuration
+. output/build-config
 
 . ./sbcl-pwd.sh
 sbcl_pwd