1 #
   2 # Copyright (c) 2011, 2018, Oracle and/or its affiliates. All rights reserved.
   3 # DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4 #
   5 # This code is free software; you can redistribute it and/or modify it
   6 # under the terms of the GNU General Public License version 2 only, as
   7 # published by the Free Software Foundation.  Oracle designates this
   8 # particular file as subject to the "Classpath" exception as provided
   9 # by Oracle in the LICENSE file that accompanied this code.
  10 #
  11 # This code is distributed in the hope that it will be useful, but WITHOUT
  12 # ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13 # FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14 # version 2 for more details (a copy is included in the LICENSE file that
  15 # accompanied this code).
  16 #
  17 # You should have received a copy of the GNU General Public License version
  18 # 2 along with this work; if not, write to the Free Software Foundation,
  19 # Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20 #
  21 # Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22 # or visit www.oracle.com if you need additional information or have any
  23 # questions.
  24 #
  25 
  26 ########################################################################
  27 # This file handles detection of the Boot JDK. The Boot JDK detection
  28 # process has been developed as a response to solve a complex real-world
  29 # problem. Initially, it was simple, but it has grown as platform after
  30 # platform, idiosyncracy after idiosyncracy has been supported.
  31 #
  32 # The basic idea is this:
  33 # 1) You need an acceptable *) JDK to use as a Boot JDK
  34 # 2) There are several ways to locate a JDK, that are mostly platform
  35 #    dependent **)
  36 # 3) You can have multiple JDKs installed
  37 # 4) If possible, configure should try to dig out an acceptable JDK
  38 #    automatically, without having to resort to command-line options
  39 #
  40 # *)  acceptable means e.g. JDK7 for building JDK8, a complete JDK (with
  41 #     javac) and not a JRE, etc.
  42 #
  43 # **) On Windows we typically use a well-known path.
  44 #     On MacOSX we typically use the tool java_home.
  45 #     On Linux we typically find javac in the $PATH, and then follow a
  46 #     chain of symlinks that often ends up in a real JDK.
  47 #
  48 # This leads to the code where we check in different ways to locate a
  49 # JDK, and if one is found, check if it is acceptable. If not, we print
  50 # our reasons for rejecting it (useful when debugging non-working
  51 # configure situations) and continue checking the next one.
  52 ########################################################################
  53 
  54 # Execute the check given as argument, and verify the result
  55 # If the Boot JDK was previously found, do nothing
  56 # $1 A command line (typically autoconf macro) to execute
  57 AC_DEFUN([BOOTJDK_DO_CHECK],
  58 [
  59   if test "x$BOOT_JDK_FOUND" = xno; then
  60     # Now execute the test
  61     $1
  62 
  63     # If previous step claimed to have found a JDK, check it to see if it seems to be valid.
  64     if test "x$BOOT_JDK_FOUND" = xmaybe; then
  65       # Do we have a bin/java?
  66       if test ! -x "$BOOT_JDK/bin/java$EXE_SUFFIX"; then
  67         AC_MSG_NOTICE([Potential Boot JDK found at $BOOT_JDK did not contain bin/java; ignoring])
  68         BOOT_JDK_FOUND=no
  69       else
  70         # Do we have a bin/javac?
  71         if test ! -x "$BOOT_JDK/bin/javac$EXE_SUFFIX"; then
  72           AC_MSG_NOTICE([Potential Boot JDK found at $BOOT_JDK did not contain bin/javac; ignoring])
  73           AC_MSG_NOTICE([(This might be an JRE instead of an JDK)])
  74           BOOT_JDK_FOUND=no
  75         else
  76           # Oh, this is looking good! We probably have found a proper JDK. Is it the correct version?
  77           BOOT_JDK_VERSION=`"$BOOT_JDK/bin/java$EXE_SUFFIX" $USER_BOOT_JDK_OPTIONS -version 2>&1 | $HEAD -n 1`
  78           if [ [[ "$BOOT_JDK_VERSION" =~ "Picked up" ]] ]; then
  79             AC_MSG_NOTICE([You have _JAVA_OPTIONS or JAVA_TOOL_OPTIONS set. This can mess up the build. Please use --with-boot-jdk-jvmargs instead.])
  80             AC_MSG_NOTICE([Java reports: "$BOOT_JDK_VERSION".])
  81             AC_MSG_ERROR([Cannot continue])
  82           fi
  83           if [ [[ "$BOOT_JDK_VERSION" =~ "Unrecognized option" ]] ]; then
  84             AC_MSG_NOTICE([The specified --with-boot-jdk-jvmargs is invalid for the tested java])
  85             AC_MSG_NOTICE([Error message: "$BOOT_JDK_VERSION".])
  86             AC_MSG_NOTICE([Please fix arguments, or point to an explicit boot JDK which accept these arguments])
  87             AC_MSG_ERROR([Cannot continue])
  88           fi
  89 
  90           # Extra M4 quote needed to protect [] in grep expression.
  91           [FOUND_CORRECT_VERSION=`$ECHO $BOOT_JDK_VERSION \
  92               | $EGREP "\"(${DEFAULT_ACCEPTABLE_BOOT_VERSIONS// /|})([\.+-].*)?\""`]
  93           if test "x$FOUND_CORRECT_VERSION" = x; then
  94             AC_MSG_NOTICE([Potential Boot JDK found at $BOOT_JDK is incorrect JDK version ($BOOT_JDK_VERSION); ignoring])
  95             AC_MSG_NOTICE([(Your Boot JDK version must be one of: $DEFAULT_ACCEPTABLE_BOOT_VERSIONS)])
  96             BOOT_JDK_FOUND=no
  97           else
  98             # We're done! :-)
  99             BOOT_JDK_FOUND=yes
 100             BASIC_FIXUP_PATH(BOOT_JDK)
 101             AC_MSG_CHECKING([for Boot JDK])
 102             AC_MSG_RESULT([$BOOT_JDK])
 103             AC_MSG_CHECKING([Boot JDK version])
 104             BOOT_JDK_VERSION=`"$BOOT_JDK/bin/java$EXE_SUFFIX" $USER_BOOT_JDK_OPTIONS -version 2>&1 | $TR '\n\r' '  '`
 105             AC_MSG_RESULT([$BOOT_JDK_VERSION])
 106           fi # end check jdk version
 107         fi # end check javac
 108       fi # end check java
 109     fi # end check boot jdk found
 110   fi
 111 ])
 112 
 113 # Test: Is bootjdk explicitly set by command line arguments?
 114 AC_DEFUN([BOOTJDK_CHECK_ARGUMENTS],
 115 [
 116   if test "x$with_boot_jdk" != x; then
 117     if test -d "$with_boot_jdk"; then
 118       BOOT_JDK=$with_boot_jdk
 119       BOOT_JDK_FOUND=maybe
 120     elif test -f "$with_boot_jdk"; then
 121       case "$with_boot_jdk" in
 122         *.tar.gz )
 123             BOOT_JDK_SUPPORT_DIR=$CONFIGURESUPPORT_OUTPUTDIR/boot-jdk
 124             $RM -rf $BOOT_JDK_SUPPORT_DIR
 125             $MKDIR -p $BOOT_JDK_SUPPORT_DIR
 126             $GUNZIP -c $with_boot_jdk | $TAR xf - -C $BOOT_JDK_SUPPORT_DIR
 127 
 128             # Try to find javac to determine BOOT_JDK path
 129             BOOT_JDK_JAVAC_PATH=`$FIND $BOOT_JDK_SUPPORT_DIR | $GREP "/bin/javac"`
 130             if test "x$BOOT_JDK_JAVAC_PATH" != x; then
 131               BOOT_JDK_FOUND=maybe
 132               BOOT_JDK=$($DIRNAME $($DIRNAME $BOOT_JDK_JAVAC_PATH))
 133             else
 134               BOOT_JDK_FOUND=no
 135             fi
 136           ;;
 137         * )
 138             BOOT_JDK_FOUND=no
 139           ;;
 140       esac
 141     else
 142       BOOT_JDK_FOUND=no
 143     fi
 144     AC_MSG_NOTICE([Found potential Boot JDK using configure arguments])
 145   fi
 146 ])
 147 
 148 # Test: Is $JAVA_HOME set?
 149 AC_DEFUN([BOOTJDK_CHECK_JAVA_HOME],
 150 [
 151   if test "x$JAVA_HOME" != x; then
 152     JAVA_HOME_PROCESSED="$JAVA_HOME"
 153     BASIC_FIXUP_PATH(JAVA_HOME_PROCESSED)
 154     if test ! -d "$JAVA_HOME_PROCESSED"; then
 155       AC_MSG_NOTICE([Your JAVA_HOME points to a non-existing directory!])
 156     else
 157       # Aha, the user has set a JAVA_HOME
 158       # let us use that as the Boot JDK.
 159       BOOT_JDK="$JAVA_HOME_PROCESSED"
 160       BOOT_JDK_FOUND=maybe
 161       AC_MSG_NOTICE([Found potential Boot JDK using JAVA_HOME])
 162     fi
 163   fi
 164 ])
 165 
 166 # Test: Is there a java or javac in the PATH, which is a symlink to the JDK?
 167 AC_DEFUN([BOOTJDK_CHECK_JAVA_IN_PATH_IS_SYMLINK],
 168 [
 169   AC_PATH_PROG(JAVAC_CHECK, javac)
 170   AC_PATH_PROG(JAVA_CHECK, java)
 171   BINARY="$JAVAC_CHECK"
 172   if test "x$JAVAC_CHECK" = x; then
 173     BINARY="$JAVA_CHECK"
 174   fi
 175   if test "x$BINARY" != x; then
 176     # So there is a java(c) binary, it might be part of a JDK.
 177     # Lets find the JDK/JRE directory by following symbolic links.
 178     # Linux/GNU systems often have links from /usr/bin/java to
 179     # /etc/alternatives/java to the real JDK binary.
 180     BASIC_REMOVE_SYMBOLIC_LINKS(BINARY)
 181     BOOT_JDK=`dirname "$BINARY"`
 182     BOOT_JDK=`cd "$BOOT_JDK/.."; pwd`
 183     if test -x "$BOOT_JDK/bin/javac" && test -x "$BOOT_JDK/bin/java"; then
 184       # Looks like we found ourselves an JDK
 185       BOOT_JDK_FOUND=maybe
 186       AC_MSG_NOTICE([Found potential Boot JDK using java(c) in PATH])
 187     fi
 188   fi
 189 ])
 190 
 191 # Test: Is there a /usr/libexec/java_home? (Typically on MacOSX)
 192 # $1: Argument to the java_home binary (optional)
 193 AC_DEFUN([BOOTJDK_CHECK_LIBEXEC_JAVA_HOME],
 194 [
 195   if test -x /usr/libexec/java_home; then
 196     BOOT_JDK=`/usr/libexec/java_home $1`
 197     BOOT_JDK_FOUND=maybe
 198     AC_MSG_NOTICE([Found potential Boot JDK using /usr/libexec/java_home $1])
 199   fi
 200 ])
 201 
 202 # Test: On MacOS X, can we find a boot jdk using /usr/libexec/java_home?
 203 AC_DEFUN([BOOTJDK_CHECK_MACOSX_JAVA_LOCATOR],
 204 [
 205   if test "x$OPENJDK_TARGET_OS" = xmacosx; then
 206     # First check at user selected default
 207     BOOTJDK_DO_CHECK([BOOTJDK_CHECK_LIBEXEC_JAVA_HOME()])
 208     # If that did not work out (e.g. too old), try explicit versions instead
 209     BOOTJDK_DO_CHECK([BOOTJDK_CHECK_LIBEXEC_JAVA_HOME([-v 1.9])])
 210     BOOTJDK_DO_CHECK([BOOTJDK_CHECK_LIBEXEC_JAVA_HOME([-v 1.8])])
 211     BOOTJDK_DO_CHECK([BOOTJDK_CHECK_LIBEXEC_JAVA_HOME([-v 1.7])])
 212   fi
 213 ])
 214 
 215 # Look for a jdk in the given path. If there are multiple, try to select the newest.
 216 # If found, set BOOT_JDK and BOOT_JDK_FOUND.
 217 # $1 = Path to directory containing jdk installations.
 218 # $2 = String to append to the found JDK directory to get the proper JDK home
 219 AC_DEFUN([BOOTJDK_FIND_BEST_JDK_IN_DIRECTORY],
 220 [
 221   BOOT_JDK_PREFIX="$1"
 222   BOOT_JDK_SUFFIX="$2"
 223   ALL_JDKS_FOUND=`$LS "$BOOT_JDK_PREFIX" 2> /dev/null | $SORT -r`
 224   if test "x$ALL_JDKS_FOUND" != x; then
 225     for JDK_TO_TRY in $ALL_JDKS_FOUND ; do
 226       BOOTJDK_DO_CHECK([
 227         BOOT_JDK="${BOOT_JDK_PREFIX}/${JDK_TO_TRY}${BOOT_JDK_SUFFIX}"
 228         if test -d "$BOOT_JDK"; then
 229           BOOT_JDK_FOUND=maybe
 230           AC_MSG_NOTICE([Found potential Boot JDK using well-known locations (in $BOOT_JDK_PREFIX/$JDK_TO_TRY)])
 231         fi
 232       ])
 233     done
 234   fi
 235 ])
 236 
 237 # Call BOOTJDK_FIND_BEST_JDK_IN_DIRECTORY, but use the given
 238 # environmental variable as base for where to look.
 239 # $1 Name of an environmal variable, assumed to point to the Program Files directory.
 240 AC_DEFUN([BOOTJDK_FIND_BEST_JDK_IN_WINDOWS_VIRTUAL_DIRECTORY],
 241 [
 242   if test "x[$]$1" != x; then
 243     VIRTUAL_DIR="[$]$1/Java"
 244     BASIC_WINDOWS_REWRITE_AS_UNIX_PATH(VIRTUAL_DIR)
 245     BOOTJDK_FIND_BEST_JDK_IN_DIRECTORY($VIRTUAL_DIR)
 246   fi
 247 ])
 248 
 249 # Test: Is there a JDK installed in default, well-known locations?
 250 AC_DEFUN([BOOTJDK_CHECK_WELL_KNOWN_LOCATIONS],
 251 [
 252   if test "x$OPENJDK_TARGET_OS" = xwindows; then
 253     BOOTJDK_DO_CHECK([BOOTJDK_FIND_BEST_JDK_IN_WINDOWS_VIRTUAL_DIRECTORY([ProgramW6432])])
 254     BOOTJDK_DO_CHECK([BOOTJDK_FIND_BEST_JDK_IN_WINDOWS_VIRTUAL_DIRECTORY([PROGRAMW6432])])
 255     BOOTJDK_DO_CHECK([BOOTJDK_FIND_BEST_JDK_IN_WINDOWS_VIRTUAL_DIRECTORY([PROGRAMFILES])])
 256     BOOTJDK_DO_CHECK([BOOTJDK_FIND_BEST_JDK_IN_WINDOWS_VIRTUAL_DIRECTORY([ProgramFiles])])
 257     BOOTJDK_DO_CHECK([BOOTJDK_FIND_BEST_JDK_IN_DIRECTORY([/cygdrive/c/Program Files/Java])])
 258   elif test "x$OPENJDK_TARGET_OS" = xmacosx; then
 259     BOOTJDK_DO_CHECK([BOOTJDK_FIND_BEST_JDK_IN_DIRECTORY([/Library/Java/JavaVirtualMachines],[/Contents/Home])])
 260     BOOTJDK_DO_CHECK([BOOTJDK_FIND_BEST_JDK_IN_DIRECTORY([/System/Library/Java/JavaVirtualMachines],[/Contents/Home])])
 261   elif test "x$OPENJDK_TARGET_OS" = xlinux; then
 262     BOOTJDK_DO_CHECK([BOOTJDK_FIND_BEST_JDK_IN_DIRECTORY([/usr/lib/jvm])])
 263   fi
 264 ])
 265 
 266 # Check that a command-line tool in the Boot JDK is correct
 267 # $1 = name of variable to assign
 268 # $2 = name of binary
 269 AC_DEFUN([BOOTJDK_CHECK_TOOL_IN_BOOTJDK],
 270 [
 271   # Use user overridden value if available, otherwise locate tool in the Boot JDK.
 272   BASIC_SETUP_TOOL($1,
 273     [
 274       AC_MSG_CHECKING([for $2 in Boot JDK])
 275       $1=$BOOT_JDK/bin/$2
 276       if test ! -x [$]$1; then
 277         AC_MSG_RESULT(not found)
 278         AC_MSG_NOTICE([Your Boot JDK seems broken. This might be fixed by explicitly setting --with-boot-jdk])
 279         AC_MSG_ERROR([Could not find $2 in the Boot JDK])
 280       fi
 281       AC_MSG_RESULT(ok)
 282       AC_SUBST($1)
 283     ])
 284 ])
 285 
 286 ###############################################################################
 287 #
 288 # We need a Boot JDK to bootstrap the build.
 289 #
 290 
 291 AC_DEFUN_ONCE([BOOTJDK_SETUP_BOOT_JDK],
 292 [
 293   BOOT_JDK_FOUND=no
 294   AC_ARG_WITH(boot-jdk, [AS_HELP_STRING([--with-boot-jdk],
 295       [path to Boot JDK (used to bootstrap build) @<:@probed@:>@])])
 296 
 297   AC_ARG_WITH(boot-jdk-jvmargs, [AS_HELP_STRING([--with-boot-jdk-jvmargs],
 298   [specify additional arguments to be passed to Boot JDK tools @<:@none@:>@])])
 299 
 300   USER_BOOT_JDK_OPTIONS="$with_boot_jdk_jvmargs"
 301 
 302   # We look for the Boot JDK through various means, going from more certain to
 303   # more of a guess-work. After each test, BOOT_JDK_FOUND is set to "yes" if
 304   # we detected something (if so, the path to the jdk is in BOOT_JDK). But we
 305   # must check if this is indeed valid; otherwise we'll continue looking.
 306 
 307   # Test: Is bootjdk explicitly set by command line arguments?
 308   BOOTJDK_DO_CHECK([BOOTJDK_CHECK_ARGUMENTS])
 309   if test "x$with_boot_jdk" != x && test "x$BOOT_JDK_FOUND" = xno; then
 310     # Having specified an argument which is incorrect will produce an instant failure;
 311     # we should not go on looking
 312     AC_MSG_ERROR([The path given by --with-boot-jdk does not contain a valid Boot JDK])
 313   fi
 314 
 315   # Test: On MacOS X, can we find a boot jdk using /usr/libexec/java_home?
 316   BOOTJDK_DO_CHECK([BOOTJDK_CHECK_MACOSX_JAVA_LOCATOR])
 317 
 318   # Test: Is $JAVA_HOME set?
 319   BOOTJDK_DO_CHECK([BOOTJDK_CHECK_JAVA_HOME])
 320 
 321   # Test: Is there a java or javac in the PATH, which is a symlink to the JDK?
 322   BOOTJDK_DO_CHECK([BOOTJDK_CHECK_JAVA_IN_PATH_IS_SYMLINK])
 323 
 324   # Test: Is there a JDK installed in default, well-known locations?
 325   BOOTJDK_DO_CHECK([BOOTJDK_CHECK_WELL_KNOWN_LOCATIONS])
 326 
 327   # If we haven't found anything yet, we've truly lost. Give up.
 328   if test "x$BOOT_JDK_FOUND" = xno; then
 329     HELP_MSG_MISSING_DEPENDENCY([openjdk])
 330     AC_MSG_NOTICE([Could not find a valid Boot JDK. $HELP_MSG])
 331     AC_MSG_NOTICE([This might be fixed by explicitly setting --with-boot-jdk])
 332     AC_MSG_ERROR([Cannot continue])
 333   fi
 334 
 335   AC_SUBST(BOOT_JDK)
 336 
 337   # Setup tools from the Boot JDK.
 338   BOOTJDK_CHECK_TOOL_IN_BOOTJDK(JAVA, java$EXE_SUFFIX)
 339   BOOTJDK_CHECK_TOOL_IN_BOOTJDK(JAVAC, javac$EXE_SUFFIX)
 340   BOOTJDK_CHECK_TOOL_IN_BOOTJDK(JAVADOC, javadoc$EXE_SUFFIX)
 341   BOOTJDK_CHECK_TOOL_IN_BOOTJDK(JAR, jar$EXE_SUFFIX)
 342   BOOTJDK_CHECK_TOOL_IN_BOOTJDK(JARSIGNER, jarsigner$EXE_SUFFIX)
 343 
 344   # Finally, set some other options...
 345 
 346   # When compiling code to be executed by the Boot JDK, force compatibility with the
 347   # oldest supported bootjdk.
 348   BOOT_JDK_SOURCETARGET="-source 9 -target 9"
 349   AC_SUBST(BOOT_JDK_SOURCETARGET)
 350 
 351   AC_SUBST(JAVAC_FLAGS)
 352 
 353   # Check if the boot jdk is 32 or 64 bit
 354   if "$JAVA" -version 2>&1 | $GREP -q "64-Bit"; then
 355     BOOT_JDK_BITS="64"
 356   else
 357     BOOT_JDK_BITS="32"
 358   fi
 359   AC_MSG_CHECKING([if Boot JDK is 32 or 64 bits])
 360   AC_MSG_RESULT([$BOOT_JDK_BITS])
 361 
 362   # Try to enable CDS
 363   AC_MSG_CHECKING([for local Boot JDK Class Data Sharing (CDS)])
 364   BOOT_JDK_CDS_ARCHIVE=$CONFIGURESUPPORT_OUTPUTDIR/classes.jsa
 365   ADD_JVM_ARG_IF_OK([-XX:+UnlockDiagnosticVMOptions -XX:-VerifySharedSpaces -XX:SharedArchiveFile=$BOOT_JDK_CDS_ARCHIVE],boot_jdk_cds_args,[$JAVA])
 366 
 367   if test "x$boot_jdk_cds_args" != x; then
 368     # Try creating a CDS archive
 369     "$JAVA" $boot_jdk_cds_args -Xshare:dump > /dev/null 2>&1
 370     if test $? -eq 0; then
 371       BOOTJDK_USE_LOCAL_CDS=true
 372       AC_MSG_RESULT([yes, created])
 373     else
 374       # Generation failed, don't use CDS.
 375       BOOTJDK_USE_LOCAL_CDS=false
 376       AC_MSG_RESULT([no, creation failed])
 377     fi
 378   else
 379     BOOTJDK_USE_LOCAL_CDS=false
 380     AC_MSG_RESULT([no, -XX:SharedArchiveFile not supported])
 381   fi
 382 ])
 383 
 384 AC_DEFUN_ONCE([BOOTJDK_SETUP_BOOT_JDK_ARGUMENTS],
 385 [
 386   ##############################################################################
 387   #
 388   # Specify jvm options for anything that is run with the Boot JDK.
 389   # Not all JVM:s accept the same arguments on the command line.
 390   #
 391   AC_MSG_CHECKING([flags for boot jdk java command] )
 392 
 393   # Force en-US environment
 394   ADD_JVM_ARG_IF_OK([-Duser.language=en -Duser.country=US],boot_jdk_jvmargs,[$JAVA])
 395 
 396   if test "x$BOOTJDK_USE_LOCAL_CDS" = xtrue; then
 397     # Use our own CDS archive
 398     ADD_JVM_ARG_IF_OK([$boot_jdk_cds_args -Xshare:auto],boot_jdk_jvmargs,[$JAVA])
 399   else
 400     # Otherwise optimistically use the system-wide one, if one is present
 401     ADD_JVM_ARG_IF_OK([-Xshare:auto],boot_jdk_jvmargs,[$JAVA])
 402   fi
 403 
 404   # Finally append user provided options to allow them to override.
 405   ADD_JVM_ARG_IF_OK([$USER_BOOT_JDK_OPTIONS],boot_jdk_jvmargs,[$JAVA])
 406 
 407   AC_MSG_RESULT([$boot_jdk_jvmargs])
 408 
 409   # For now, general JAVA_FLAGS are the same as the boot jdk jvmargs
 410   JAVA_FLAGS=$boot_jdk_jvmargs
 411   AC_SUBST(JAVA_FLAGS)
 412 
 413   AC_MSG_CHECKING([flags for boot jdk java command for big workloads])
 414 
 415   # Starting amount of heap memory.
 416   ADD_JVM_ARG_IF_OK([-Xms64M],boot_jdk_jvmargs_big,[$JAVA])
 417   BOOTCYCLE_JVM_ARGS_BIG=-Xms64M
 418 
 419   # Maximum amount of heap memory and stack size.
 420   JVM_HEAP_LIMIT_32="768"
 421   # Running a 64 bit JVM allows for and requires a bigger heap
 422   JVM_HEAP_LIMIT_64="1600"
 423   STACK_SIZE_32=768
 424   STACK_SIZE_64=1536
 425   JVM_HEAP_LIMIT_GLOBAL=`expr $MEMORY_SIZE / 2`
 426   if test "$JVM_HEAP_LIMIT_GLOBAL" -lt "$JVM_HEAP_LIMIT_32"; then
 427     JVM_HEAP_LIMIT_32=$JVM_HEAP_LIMIT_GLOBAL
 428   fi
 429   if test "$JVM_HEAP_LIMIT_GLOBAL" -lt "$JVM_HEAP_LIMIT_64"; then
 430     JVM_HEAP_LIMIT_64=$JVM_HEAP_LIMIT_GLOBAL
 431   fi
 432   if test "$JVM_HEAP_LIMIT_GLOBAL" -lt "512"; then
 433     JVM_HEAP_LIMIT_32=512
 434     JVM_HEAP_LIMIT_64=512
 435   fi
 436 
 437   if test "x$BOOT_JDK_BITS" = "x32"; then
 438     STACK_SIZE=$STACK_SIZE_32
 439     JVM_MAX_HEAP=$JVM_HEAP_LIMIT_32
 440   else
 441     STACK_SIZE=$STACK_SIZE_64
 442     JVM_MAX_HEAP=$JVM_HEAP_LIMIT_64
 443   fi
 444   ADD_JVM_ARG_IF_OK([-Xmx${JVM_MAX_HEAP}M],boot_jdk_jvmargs_big,[$JAVA])
 445   ADD_JVM_ARG_IF_OK([-XX:ThreadStackSize=$STACK_SIZE],boot_jdk_jvmargs_big,[$JAVA])
 446 
 447   AC_MSG_RESULT([$boot_jdk_jvmargs_big])
 448 
 449   JAVA_FLAGS_BIG=$boot_jdk_jvmargs_big
 450   AC_SUBST(JAVA_FLAGS_BIG)
 451 
 452   if test "x$OPENJDK_TARGET_CPU_BITS" = "x32"; then
 453     BOOTCYCLE_MAX_HEAP=$JVM_HEAP_LIMIT_32
 454     BOOTCYCLE_STACK_SIZE=$STACK_SIZE_32
 455   else
 456     BOOTCYCLE_MAX_HEAP=$JVM_HEAP_LIMIT_64
 457     BOOTCYCLE_STACK_SIZE=$STACK_SIZE_64
 458   fi
 459   BOOTCYCLE_JVM_ARGS_BIG="$BOOTCYCLE_JVM_ARGS_BIG -Xmx${BOOTCYCLE_MAX_HEAP}M"
 460   BOOTCYCLE_JVM_ARGS_BIG="$BOOTCYCLE_JVM_ARGS_BIG -XX:ThreadStackSize=$BOOTCYCLE_STACK_SIZE"
 461   AC_MSG_CHECKING([flags for bootcycle boot jdk java command for big workloads])
 462   AC_MSG_RESULT([$BOOTCYCLE_JVM_ARGS_BIG])
 463   AC_SUBST(BOOTCYCLE_JVM_ARGS_BIG)
 464 
 465   # By default, the main javac compilations use big
 466   JAVA_FLAGS_JAVAC="$JAVA_FLAGS_BIG"
 467   AC_SUBST(JAVA_FLAGS_JAVAC)
 468 
 469   AC_MSG_CHECKING([flags for boot jdk java command for small workloads])
 470 
 471   # Use serial gc for small short lived tools if possible
 472   ADD_JVM_ARG_IF_OK([-XX:+UseSerialGC],boot_jdk_jvmargs_small,[$JAVA])
 473   ADD_JVM_ARG_IF_OK([-Xms32M],boot_jdk_jvmargs_small,[$JAVA])
 474   ADD_JVM_ARG_IF_OK([-Xmx512M],boot_jdk_jvmargs_small,[$JAVA])
 475   ADD_JVM_ARG_IF_OK([-XX:TieredStopAtLevel=1],boot_jdk_jvmargs_small,[$JAVA])
 476 
 477   AC_MSG_RESULT([$boot_jdk_jvmargs_small])
 478 
 479   JAVA_FLAGS_SMALL=$boot_jdk_jvmargs_small
 480   AC_SUBST(JAVA_FLAGS_SMALL)
 481 
 482   JAVA_TOOL_FLAGS_SMALL=""
 483   for f in $JAVA_FLAGS_SMALL; do
 484     JAVA_TOOL_FLAGS_SMALL="$JAVA_TOOL_FLAGS_SMALL -J$f"
 485   done
 486   AC_SUBST(JAVA_TOOL_FLAGS_SMALL)
 487 ])
 488 
 489 # BUILD_JDK: the location of the latest JDK that can run
 490 #   on the host system and supports the target class file version
 491 #   generated in this JDK build.  This variable should only be
 492 #   used after the launchers are built.
 493 #
 494 
 495 # Execute the check given as argument, and verify the result.
 496 # If the JDK was previously found, do nothing.
 497 # $1 A command line (typically autoconf macro) to execute
 498 AC_DEFUN([BOOTJDK_CHECK_BUILD_JDK],
 499 [
 500   if test "x$BUILD_JDK_FOUND" = xno; then
 501     # Execute the test
 502     $1
 503 
 504     # If previous step claimed to have found a JDK, check it to see if it seems to be valid.
 505     if test "x$BUILD_JDK_FOUND" = xmaybe; then
 506       # Do we have a bin/java?
 507       if test ! -x "$BUILD_JDK/bin/java"; then
 508         AC_MSG_NOTICE([Potential Build JDK found at $BUILD_JDK did not contain bin/java; ignoring])
 509         BUILD_JDK_FOUND=no
 510       elif test ! -x "$BUILD_JDK/bin/jlink"; then
 511         AC_MSG_NOTICE([Potential Build JDK found at $BUILD_JDK did not contain bin/jlink; ignoring])
 512         BUILD_JDK_FOUND=no
 513       elif test ! -x "$BUILD_JDK/bin/jmod"; then
 514         AC_MSG_NOTICE([Potential Build JDK found at $BUILD_JDK did not contain bin/jmod; ignoring])
 515         BUILD_JDK_FOUND=no
 516       elif test ! -x "$BUILD_JDK/bin/javac"; then
 517         # Do we have a bin/javac?
 518         AC_MSG_NOTICE([Potential Build JDK found at $BUILD_JDK did not contain bin/javac; ignoring])
 519         AC_MSG_NOTICE([(This might be a JRE instead of an JDK)])
 520         BUILD_JDK_FOUND=no
 521       else
 522         # Oh, this is looking good! We probably have found a proper JDK. Is it the correct version?
 523         BUILD_JDK_VERSION=`"$BUILD_JDK/bin/java" -version 2>&1 | $HEAD -n 1`
 524 
 525         # Extra M4 quote needed to protect [] in grep expression.
 526         [FOUND_CORRECT_VERSION=`echo $BUILD_JDK_VERSION | $EGREP "\"$VERSION_FEATURE([\.+-].*)?\""`]
 527         if test "x$FOUND_CORRECT_VERSION" = x; then
 528           AC_MSG_NOTICE([Potential Build JDK found at $BUILD_JDK is incorrect JDK version ($BUILD_JDK_VERSION); ignoring])
 529           AC_MSG_NOTICE([(Your Build JDK must be version $VERSION_FEATURE)])
 530           BUILD_JDK_FOUND=no
 531         else
 532           # We're done!
 533           BUILD_JDK_FOUND=yes
 534           BASIC_FIXUP_PATH(BUILD_JDK)
 535           AC_MSG_CHECKING([for Build JDK])
 536           AC_MSG_RESULT([$BUILD_JDK])
 537           AC_MSG_CHECKING([Build JDK version])
 538           BUILD_JDK_VERSION=`"$BUILD_JDK/bin/java" -version 2>&1 | $TR '\n\r' '  '`
 539           AC_MSG_RESULT([$BUILD_JDK_VERSION])
 540         fi # end check jdk version
 541       fi # end check java
 542     fi # end check build jdk found
 543   fi
 544 ])
 545 
 546 # By default the BUILD_JDK is the JDK_OUTPUTDIR.  If the target architecture
 547 # is different than the host system doing the build (e.g. cross-compilation),
 548 # a special BUILD_JDK is built as part of the build process.  An external
 549 # prebuilt BUILD_JDK can also be supplied.
 550 AC_DEFUN([BOOTJDK_SETUP_BUILD_JDK],
 551 [
 552   AC_ARG_WITH(build-jdk, [AS_HELP_STRING([--with-build-jdk],
 553       [path to JDK of same version as is being built@<:@the newly built JDK@:>@])])
 554 
 555   CREATE_BUILDJDK=false
 556   EXTERNAL_BUILDJDK=false
 557   BUILD_JDK_FOUND="no"
 558   if test "x$with_build_jdk" != "x"; then
 559     BOOTJDK_CHECK_BUILD_JDK([
 560        if test "x$with_build_jdk" != x; then
 561          BUILD_JDK=$with_build_jdk
 562          BUILD_JDK_FOUND=maybe
 563          AC_MSG_NOTICE([Found potential Build JDK using configure arguments])
 564        fi])
 565     EXTERNAL_BUILDJDK=true
 566   else
 567     if test "x$COMPILE_TYPE" = "xcross"; then
 568       BUILD_JDK="\$(BUILDJDK_OUTPUTDIR)/jdk"
 569       BUILD_JDK_FOUND=yes
 570       CREATE_BUILDJDK=true
 571       AC_MSG_CHECKING([for Build JDK])
 572       AC_MSG_RESULT([yes, will build it for the host platform])
 573     else
 574       BUILD_JDK="\$(JDK_OUTPUTDIR)"
 575       BUILD_JDK_FOUND=yes
 576       AC_MSG_CHECKING([for Build JDK])
 577       AC_MSG_RESULT([yes, will use output dir])
 578     fi
 579   fi
 580 
 581   JMOD="$BUILD_JDK/bin/jmod"
 582   JLINK="$BUILD_JDK/bin/jlink"
 583   AC_SUBST(JMOD)
 584   AC_SUBST(JLINK)
 585 
 586   if test "x$BUILD_JDK_FOUND" != "xyes"; then
 587     AC_MSG_CHECKING([for Build JDK])
 588     AC_MSG_RESULT([no])
 589     AC_MSG_ERROR([Could not find a suitable Build JDK])
 590   fi
 591 
 592   AC_SUBST(CREATE_BUILDJDK)
 593   AC_SUBST(BUILD_JDK)
 594   AC_SUBST(EXTERNAL_BUILDJDK)
 595 ])