autoconf/configure.ac

dnl === configure.ac --------------------------------------------------------===
dnl                     The LLVM Compiler Infrastructure
dnl
dnl This file is distributed under the University of Illinois Open Source
dnl License. See LICENSE.TXT for details.
dnl
dnl===-----------------------------------------------------------------------===
dnl This is the LLVM configuration script. It is processed by the autoconf
dnl program to produce a script named configure. This script contains the
dnl configuration checks that LLVM needs in order to support multiple platforms.
dnl This file is composed of 10 sections per the recommended organization of
dnl autoconf input defined in the autoconf documentation. As this file evolves,
dnl please keep the various types of checks within their sections. The sections
dnl are as follows:
dnl
dnl SECTION 1: Initialization & Setup
dnl SECTION 2: Architecture, target, and host checks
dnl SECTION 3: Command line arguments for the configure script.
dnl SECTION 4: Check for programs we need and that they are the right version
dnl SECTION 5: Check for libraries
dnl SECTION 6: Check for header files
dnl SECTION 7: Check for types and structures
dnl SECTION 8: Check for specific functions needed
dnl SECTION 9: Additional checks, variables, etc.
dnl SECTION 10: Specify the output files and generate it
dnl
dnl===-----------------------------------------------------------------------===
dnl===
dnl=== SECTION 1: Initialization & Setup
dnl===
dnl===-----------------------------------------------------------------------===
dnl Initialize autoconf and define the package name, version number and
dnl email address for reporting bugs.
AC_INIT([[llvm]],[[2.7svn]],[llvmbugs@cs.uiuc.edu])

dnl Provide a copyright substitution and ensure the copyright notice is included
dnl in the output of --version option of the generated configure script.
AC_SUBST(LLVM_COPYRIGHT,["Copyright (c) 2003-2009 University of Illinois at Urbana-Champaign."])
AC_COPYRIGHT([Copyright (c) 2003-2009 University of Illinois at Urbana-Champaign.])

dnl Indicate that we require autoconf 2.59 or later. Ths is needed because we
dnl use some autoconf macros only available in 2.59.
AC_PREREQ(2.59)

dnl Verify that the source directory is valid. This makes sure that we are
dnl configuring LLVM and not some other package (it validates --srcdir argument)
AC_CONFIG_SRCDIR([lib/VMCore/Module.cpp])

dnl Place all of the extra autoconf files into the config subdirectory. Tell
dnl various tools where the m4 autoconf macros are.
AC_CONFIG_AUX_DIR([autoconf])

dnl Quit if the source directory has already been configured.
dnl NOTE: This relies upon undocumented autoconf behavior.
if test ${srcdir} != "." ; then
  if test -f ${srcdir}/include/llvm/Config/config.h ; then
    AC_MSG_ERROR([Already configured in ${srcdir}])
  fi
fi

dnl Configure all of the projects present in our source tree. While we could
dnl just AC_CONFIG_SUBDIRS on the set of directories in projects that have a
dnl configure script, that usage of the AC_CONFIG_SUBDIRS macro is deprecated.
dnl Instead we match on the known projects.
for i in `ls ${srcdir}/projects`
do
  if test -d ${srcdir}/projects/${i} ; then
    case ${i} in
      CVS) ;;
      sample)       AC_CONFIG_SUBDIRS([projects/sample])    ;;
      privbracket)  AC_CONFIG_SUBDIRS([projects/privbracket]) ;;
      llvm-stacker) AC_CONFIG_SUBDIRS([projects/llvm-stacker]) ;;
      # llvm-test is the old name of the test-suite, kept here for backwards
      # compatibility
      llvm-test)    AC_CONFIG_SUBDIRS([projects/llvm-test]) ;;
      test-suite)   AC_CONFIG_SUBDIRS([projects/test-suite]) ;;
      llvm-reopt)   AC_CONFIG_SUBDIRS([projects/llvm-reopt]);;
      llvm-gcc)     AC_CONFIG_SUBDIRS([projects/llvm-gcc])  ;;
      llvm-java)    AC_CONFIG_SUBDIRS([projects/llvm-java]) ;;
      llvm-tv)      AC_CONFIG_SUBDIRS([projects/llvm-tv])   ;;
      llvm-poolalloc) AC_CONFIG_SUBDIRS([projects/llvm-poolalloc]) ;;
      poolalloc)    AC_CONFIG_SUBDIRS([projects/poolalloc]) ;;
      llvm-kernel)  AC_CONFIG_SUBDIRS([projects/llvm-kernel]) ;;
      *)
        AC_MSG_WARN([Unknown project (${i}) won't be configured automatically])
        ;;
    esac
  fi
done

dnl===-----------------------------------------------------------------------===
dnl===
dnl=== SECTION 2: Architecture, target, and host checks
dnl===
dnl===-----------------------------------------------------------------------===

dnl Check the target for which we're compiling and the host that will do the
dnl compilations. This will tell us which LLVM compiler will be used for
dnl compiling SSA into object code. This needs to be done early because
dnl following tests depend on it.
AC_CANONICAL_TARGET

dnl Determine the platform type and cache its value. This helps us configure
dnl the System library to the correct build platform.
AC_CACHE_CHECK([type of operating system we're going to host on],
               [llvm_cv_os_type],
[case $host in
  *-*-aix*)
    llvm_cv_link_all_option="-Wl,--whole-archive"
    llvm_cv_no_link_all_option="-Wl,--no-whole-archive"
    llvm_cv_os_type="AIX"
    llvm_cv_platform_type="Unix" ;;
  *-*-irix*)
    llvm_cv_link_all_option="-Wl,--whole-archive"
    llvm_cv_no_link_all_option="-Wl,--no-whole-archive"
    llvm_cv_os_type="IRIX"
    llvm_cv_platform_type="Unix" ;;
  *-*-cygwin*)
    llvm_cv_link_all_option="-Wl,--whole-archive"
    llvm_cv_no_link_all_option="-Wl,--no-whole-archive"
    llvm_cv_os_type="Cygwin"
    llvm_cv_platform_type="Unix" ;;
  *-*-darwin*)
    llvm_cv_link_all_option="-Wl,-all_load"
    llvm_cv_no_link_all_option="-Wl,-noall_load"
    llvm_cv_os_type="Darwin"
    llvm_cv_platform_type="Unix" ;;
  *-*-freebsd*)
    llvm_cv_link_all_option="-Wl,--whole-archive"
    llvm_cv_no_link_all_option="-Wl,--no-whole-archive"
    llvm_cv_os_type="FreeBSD"
    llvm_cv_platform_type="Unix" ;;
  *-*-openbsd*)
    llvm_cv_link_all_option="-Wl,--whole-archive"
    llvm_cv_no_link_all_option="-Wl,--no-whole-archive"
    llvm_cv_os_type="OpenBSD"
    llvm_cv_platform_type="Unix" ;;
  *-*-netbsd*)
    llvm_cv_link_all_option="-Wl,--whole-archive"
    llvm_cv_no_link_all_option="-Wl,--no-whole-archive"
    llvm_cv_os_type="NetBSD"
    llvm_cv_platform_type="Unix" ;;
  *-*-dragonfly*)
    llvm_cv_link_all_option="-Wl,--whole-archive"
    llvm_cv_no_link_all_option="-Wl,--no-whole-archive"
    llvm_cv_os_type="DragonFly"
    llvm_cv_platform_type="Unix" ;;
  *-*-hpux*)
    llvm_cv_link_all_option="-Wl,--whole-archive"
    llvm_cv_no_link_all_option="-Wl,--no-whole-archive"
    llvm_cv_os_type="HP-UX"
    llvm_cv_platform_type="Unix" ;;
  *-*-interix*)
    llvm_cv_link_all_option="-Wl,--whole-archive"
    llvm_cv_no_link_all_option="-Wl,--no-whole-archive"
    llvm_cv_os_type="Interix"
    llvm_cv_platform_type="Unix" ;;
  *-*-linux*)
    llvm_cv_link_all_option="-Wl,--whole-archive"
    llvm_cv_no_link_all_option="-Wl,--no-whole-archive"
    llvm_cv_os_type="Linux"
    llvm_cv_platform_type="Unix" ;;
  *-*-solaris*)
    llvm_cv_link_all_option="-Wl,-z,allextract"
    llvm_cv_no_link_all_option="-Wl,-z,defaultextract"
    llvm_cv_os_type="SunOS"
    llvm_cv_platform_type="Unix" ;;
  *-*-auroraux*)
    llvm_cv_link_all_option="-Wl,-z,allextract"
    llvm_cv_link_all_option="-Wl,-z,defaultextract"
    llvm_cv_os_type="AuroraUX"
    llvm_cv_platform_type="Unix" ;;
  *-*-win32*)
    llvm_cv_link_all_option="-Wl,--whole-archive"
    llvm_cv_no_link_all_option="-Wl,--no-whole-archive"
    llvm_cv_os_type="Win32"
    llvm_cv_platform_type="Win32" ;;
  *-*-mingw*)
    llvm_cv_link_all_option="-Wl,--whole-archive"
    llvm_cv_no_link_all_option="-Wl,--no-whole-archive"
    llvm_cv_os_type="MingW"
    llvm_cv_platform_type="Win32" ;;
  *-*-haiku*)
    llvm_cv_link_all_option="-Wl,--whole-archive"
    llvm_cv_no_link_all_option="-Wl,--no-whole-archive"
    llvm_cv_os_type="Haiku"
    llvm_cv_platform_type="Unix" ;;  
  *-unknown-eabi*)
    llvm_cv_link_all_option="-Wl,--whole-archive"
    llvm_cv_no_link_all_option="-Wl,--no-whole-archive"
    llvm_cv_os_type="Freestanding"
    llvm_cv_platform_type="Unix" ;;
  *-unknown-elf*)
    llvm_cv_link_all_option="-Wl,--whole-archive"
    llvm_cv_no_link_all_option="-Wl,--no-whole-archive"
    llvm_cv_os_type="Freestanding"
    llvm_cv_platform_type="Unix" ;;
  *)
    llvm_cv_link_all_option=""
    llvm_cv_no_link_all_option=""
    llvm_cv_os_type="Unknown"
    llvm_cv_platform_type="Unknown" ;;
esac])

AC_CACHE_CHECK([type of operating system we're going to target],
               [llvm_cv_target_os_type],
[case $target in
  *-*-aix*)
    llvm_cv_target_os_type="AIX" ;;
  *-*-irix*)
    llvm_cv_target_os_type="IRIX" ;;
  *-*-cygwin*)
    llvm_cv_target_os_type="Cygwin" ;;
  *-*-darwin*)
    llvm_cv_target_os_type="Darwin" ;;
  *-*-freebsd*)
    llvm_cv_target_os_type="FreeBSD" ;;
  *-*-openbsd*)
    llvm_cv_target_os_type="OpenBSD" ;;
  *-*-netbsd*)
    llvm_cv_target_os_type="NetBSD" ;;
  *-*-dragonfly*)
    llvm_cv_target_os_type="DragonFly" ;;
  *-*-hpux*)
    llvm_cv_target_os_type="HP-UX" ;;
  *-*-interix*)
    llvm_cv_target_os_type="Interix" ;;
  *-*-linux*)
    llvm_cv_target_os_type="Linux" ;;
  *-*-solaris*)
    llvm_cv_target_os_type="SunOS" ;;
  *-*-auroraux*)
    llvm_cv_target_os_type="AuroraUX" ;;
  *-*-win32*)
    llvm_cv_target_os_type="Win32" ;;
  *-*-mingw*)
    llvm_cv_target_os_type="MingW" ;;
  *-*-haiku*)
    llvm_cv_target_os_type="Haiku" ;;  
  *-unknown-eabi*)
    llvm_cv_target_os_type="Freestanding" ;;
  *)
    llvm_cv_target_os_type="Unknown" ;;
esac])

dnl Make sure we aren't attempting to configure for an unknown system
if test "$llvm_cv_os_type" = "Unknown" ; then
  AC_MSG_ERROR([Operating system is unknown, configure can't continue])
fi

dnl Set the "OS" Makefile variable based on the platform type so the
dnl makefile can configure itself to specific build hosts
AC_SUBST(OS,$llvm_cv_os_type)
AC_SUBST(HOST_OS,$llvm_cv_os_type)
AC_SUBST(TARGET_OS,$llvm_cv_target_os_type)

dnl Set the LINKALL and NOLINKALL Makefile variables based on the platform
AC_SUBST(LINKALL,$llvm_cv_link_all_option)
AC_SUBST(NOLINKALL,$llvm_cv_no_link_all_option)

dnl Set the "LLVM_ON_*" variables based on llvm_cvs_platform_type
dnl This is used by lib/System to determine the basic kind of implementation
dnl to use.
case $llvm_cv_platform_type in
  Unix)
    AC_DEFINE([LLVM_ON_UNIX],[1],[Define if this is Unixish platform])
    AC_SUBST(LLVM_ON_UNIX,[1])
    AC_SUBST(LLVM_ON_WIN32,[0])
    ;;
  Win32)
    AC_DEFINE([LLVM_ON_WIN32],[1],[Define if this is Win32ish platform])
    AC_SUBST(LLVM_ON_UNIX,[0])
    AC_SUBST(LLVM_ON_WIN32,[1])
    ;;
esac

dnl Determine what our target architecture is and configure accordingly.
dnl This will allow Makefiles to make a distinction between the hardware and
dnl the OS.
AC_CACHE_CHECK([target architecture],[llvm_cv_target_arch],
[case $target in
  i?86-*)                 llvm_cv_target_arch="x86" ;;
  amd64-* | x86_64-*)     llvm_cv_target_arch="x86_64" ;;
  sparc*-*)               llvm_cv_target_arch="Sparc" ;;
  powerpc*-*)             llvm_cv_target_arch="PowerPC" ;;
  alpha*-*)               llvm_cv_target_arch="Alpha" ;;
  arm*-*)                 llvm_cv_target_arch="ARM" ;;
  mips-*)                 llvm_cv_target_arch="Mips" ;;
  pic16-*)                llvm_cv_target_arch="PIC16" ;;
  xcore-*)                llvm_cv_target_arch="XCore" ;;
  msp430-*)               llvm_cv_target_arch="MSP430" ;;
  s390x-*)                llvm_cv_target_arch="SystemZ" ;;
  bfin-*)                 llvm_cv_target_arch="Blackfin" ;;
  *)                      llvm_cv_target_arch="Unknown" ;;
esac])

if test "$llvm_cv_target_arch" = "Unknown" ; then
  AC_MSG_WARN([Configuring LLVM for an unknown target archicture])
fi

# Determine the LLVM native architecture for the target
case "$llvm_cv_target_arch" in
    x86)     LLVM_NATIVE_ARCH="X86" ;;
    x86_64)  LLVM_NATIVE_ARCH="X86" ;;
    *)       LLVM_NATIVE_ARCH="$llvm_cv_target_arch" ;;
esac

dnl Define a substitution, ARCH, for the target architecture
AC_SUBST(ARCH,$llvm_cv_target_arch)

dnl Check for the endianness of the target
AC_C_BIGENDIAN(AC_SUBST([ENDIAN],[big]),AC_SUBST([ENDIAN],[little]))

dnl Check for build platform executable suffix if we're crosscompiling
if test "$cross_compiling" = yes; then
  AC_SUBST(LLVM_CROSS_COMPILING, [1])
  AC_BUILD_EXEEXT
  ac_build_prefix=${build_alias}-
  AC_CHECK_PROG(BUILD_CXX, ${ac_build_prefix}g++, ${ac_build_prefix}g++)
  if test -z "$BUILD_CXX"; then
     AC_CHECK_PROG(BUILD_CXX, g++, g++)
     if test -z "$BUILD_CXX"; then
       AC_CHECK_PROG(BUILD_CXX, c++, c++, , , /usr/ucb/c++)
     fi
  fi
else
  AC_SUBST(LLVM_CROSS_COMPILING, [0])
fi

dnl Check to see if there's a "CVS" (or .svn or .git) directory indicating
dnl that this build is being done from a checkout. This sets up several
dnl defaults for the command line switches. When we build with a CVS directory,
dnl we get a debug with assertions turned on. Without, we assume a source
dnl release and we get an optimized build without assertions.
dnl See --enable-optimized and --enable-assertions below
if test -d "CVS" -o -d "${srcdir}/CVS" -o -d ".svn" -o -d "${srcdir}/.svn" -o -d ".git" -o -d "${srcdir}/.git"; then
  cvsbuild="yes"
  optimize="no"
  AC_SUBST(CVSBUILD,[[CVSBUILD=1]])
else
  cvsbuild="no"
  optimize="yes"
fi

dnl===-----------------------------------------------------------------------===
dnl===
dnl=== SECTION 3: Command line arguments for the configure script.
dnl===
dnl===-----------------------------------------------------------------------===

dnl --enable-optimized : check whether they want to do an optimized build:
AC_ARG_ENABLE(optimized, AS_HELP_STRING(
 --enable-optimized,[Compile with optimizations enabled (default is NO)]),,enableval=$optimize)
if test ${enableval} = "no" ; then
  AC_SUBST(ENABLE_OPTIMIZED,[[]])
else
  AC_SUBST(ENABLE_OPTIMIZED,[[ENABLE_OPTIMIZED=1]])
fi

dnl --enable-profiling : check whether they want to do a profile build:
AC_ARG_ENABLE(profiling, AS_HELP_STRING(
 --enable-profiling,[Compile with profiling enabled (default is NO)]),,enableval="no")
if test ${enableval} = "no" ; then
  AC_SUBST(ENABLE_PROFILING,[[]])
else
  AC_SUBST(ENABLE_PROFILING,[[ENABLE_PROFILING=1]])
fi

dnl --enable-assertions : check whether they want to turn on assertions or not:
AC_ARG_ENABLE(assertions,AS_HELP_STRING(
  --enable-assertions,[Compile with assertion checks enabled (default is YES)]),, enableval="yes")
if test ${enableval} = "yes" ; then
  AC_SUBST(DISABLE_ASSERTIONS,[[]])
else
  AC_SUBST(DISABLE_ASSERTIONS,[[DISABLE_ASSERTIONS=1]])
fi

dnl --enable-expensive-checks : check whether they want to turn on expensive debug checks:
AC_ARG_ENABLE(expensive-checks,AS_HELP_STRING(
  --enable-expensive-checks,[Compile with expensive debug checks enabled (default is NO)]),, enableval="no")
if test ${enableval} = "yes" ; then
  AC_SUBST(ENABLE_EXPENSIVE_CHECKS,[[ENABLE_EXPENSIVE_CHECKS=1]])
  AC_SUBST(EXPENSIVE_CHECKS,[[yes]])
else
  AC_SUBST(ENABLE_EXPENSIVE_CHECKS,[[]])
  AC_SUBST(EXPENSIVE_CHECKS,[[no]])
fi

dnl --enable-debug-runtime : should runtime libraries have debug symbols?
AC_ARG_ENABLE(debug-runtime,
   AS_HELP_STRING(--enable-debug-runtime,[Build runtime libs with debug symbols (default is NO)]),,enableval=no)
if test ${enableval} = "no" ; then
  AC_SUBST(DEBUG_RUNTIME,[[]])
else
  AC_SUBST(DEBUG_RUNTIME,[[DEBUG_RUNTIME=1]])
fi

dnl --enable-debug-symbols : should even optimized compiler libraries
dnl have debug symbols?
AC_ARG_ENABLE(debug-symbols,
   AS_HELP_STRING(--enable-debug-symbols,[Build compiler with debug symbols (default is NO if optimization is on and YES if it's off)]),,enableval=no)
if test ${enableval} = "no" ; then
  AC_SUBST(DEBUG_SYMBOLS,[[]])
else
  AC_SUBST(DEBUG_SYMBOLS,[[DEBUG_SYMBOLS=1]])
fi

dnl --enable-jit: check whether they want to enable the jit
AC_ARG_ENABLE(jit,
  AS_HELP_STRING(--enable-jit,
                 [Enable Just In Time Compiling (default is YES)]),,
  enableval=default)
if test ${enableval} = "no"
then
  AC_SUBST(JIT,[[]])
else
  case "$llvm_cv_target_arch" in
    x86)         AC_SUBST(TARGET_HAS_JIT,1) ;;
    Sparc)       AC_SUBST(TARGET_HAS_JIT,0) ;;
    PowerPC)     AC_SUBST(TARGET_HAS_JIT,1) ;;
    x86_64)      AC_SUBST(TARGET_HAS_JIT,1) ;;
    Alpha)       AC_SUBST(TARGET_HAS_JIT,1) ;;
    ARM)         AC_SUBST(TARGET_HAS_JIT,1) ;;
    Mips)        AC_SUBST(TARGET_HAS_JIT,0) ;;
    PIC16)       AC_SUBST(TARGET_HAS_JIT,0) ;;
    XCore)       AC_SUBST(TARGET_HAS_JIT,0) ;;
    MSP430)      AC_SUBST(TARGET_HAS_JIT,0) ;;
    SystemZ)     AC_SUBST(TARGET_HAS_JIT,0) ;;
    Blackfin)    AC_SUBST(TARGET_HAS_JIT,0) ;;
    *)           AC_SUBST(TARGET_HAS_JIT,0) ;;
  esac
fi

dnl Allow enablement of doxygen generated documentation
AC_ARG_ENABLE(doxygen,
              AS_HELP_STRING([--enable-doxygen],
                             [Build doxygen documentation (default is NO)]),,
                             enableval=default)
case "$enableval" in
  yes) AC_SUBST(ENABLE_DOXYGEN,[1]) ;;
  no)  AC_SUBST(ENABLE_DOXYGEN,[0]) ;;
  default) AC_SUBST(ENABLE_DOXYGEN,[0]) ;;
  *) AC_MSG_ERROR([Invalid setting for --enable-doxygen. Use "yes" or "no"]) ;;
esac

dnl Allow disablement of threads
AC_ARG_ENABLE(threads,
              AS_HELP_STRING([--enable-threads],
                             [Use threads if available (default is YES)]),,
                             enableval=default)
case "$enableval" in
  yes) AC_SUBST(ENABLE_THREADS,[1]) ;;
  no)  AC_SUBST(ENABLE_THREADS,[0]) ;;
  default) AC_SUBST(ENABLE_THREADS,[1]) ;;
  *) AC_MSG_ERROR([Invalid setting for --enable-threads. Use "yes" or "no"]) ;;
esac
AC_DEFINE_UNQUOTED([ENABLE_THREADS],$ENABLE_THREADS,[Define if threads enabled])

dnl Allow building without position independent code
AC_ARG_ENABLE(pic,
  AS_HELP_STRING([--enable-pic],
                 [Build LLVM with Position Independent Code (default is YES)]),,
                 enableval=default)
case "$enableval" in
  yes) AC_SUBST(ENABLE_PIC,[1]) ;;
  no)  AC_SUBST(ENABLE_PIC,[0]) ;;
  default) AC_SUBST(ENABLE_PIC,[1]) ;;
  *) AC_MSG_ERROR([Invalid setting for --enable-pic. Use "yes" or "no"]) ;;
esac
AC_DEFINE_UNQUOTED([ENABLE_PIC],$ENABLE_PIC,
                   [Define if position independent code is enabled])

dnl Allow specific targets to be specified for building (or not)
TARGETS_TO_BUILD=""
AC_ARG_ENABLE([targets],AS_HELP_STRING([--enable-targets],
    [Build specific host targets: all or target1,target2,... Valid targets are:
     host, x86, x86_64, sparc, powerpc, alpha, arm, mips, spu, pic16,
     xcore, msp430, systemz, blackfin, cbe, msil, and cpp (default=all)]),,
    enableval=all)
if test "$enableval" = host-only ; then
  enableval=host
fi
case "$enableval" in
  all) TARGETS_TO_BUILD="X86 Sparc PowerPC Alpha ARM Mips CellSPU PIC16 XCore MSP430 SystemZ Blackfin CBackend MSIL CppBackend" ;;
  *)for a_target in `echo $enableval|sed -e 's/,/ /g' ` ; do
      case "$a_target" in
        x86)      TARGETS_TO_BUILD="X86 $TARGETS_TO_BUILD" ;;
        x86_64)   TARGETS_TO_BUILD="X86 $TARGETS_TO_BUILD" ;;
        sparc)    TARGETS_TO_BUILD="Sparc $TARGETS_TO_BUILD" ;;
        powerpc)  TARGETS_TO_BUILD="PowerPC $TARGETS_TO_BUILD" ;;
        alpha)    TARGETS_TO_BUILD="Alpha $TARGETS_TO_BUILD" ;;
        arm)      TARGETS_TO_BUILD="ARM $TARGETS_TO_BUILD" ;;
        mips)     TARGETS_TO_BUILD="Mips $TARGETS_TO_BUILD" ;;
        spu)      TARGETS_TO_BUILD="CellSPU $TARGETS_TO_BUILD" ;;
        pic16)    TARGETS_TO_BUILD="PIC16 $TARGETS_TO_BUILD" ;;
        xcore)    TARGETS_TO_BUILD="XCore $TARGETS_TO_BUILD" ;;
        msp430)   TARGETS_TO_BUILD="MSP430 $TARGETS_TO_BUILD" ;;
        systemz)  TARGETS_TO_BUILD="SystemZ $TARGETS_TO_BUILD" ;;
        blackfin) TARGETS_TO_BUILD="Blackfin $TARGETS_TO_BUILD" ;;
        cbe)      TARGETS_TO_BUILD="CBackend $TARGETS_TO_BUILD" ;;
        msil)     TARGETS_TO_BUILD="MSIL $TARGETS_TO_BUILD" ;;
        cpp)      TARGETS_TO_BUILD="CppBackend $TARGETS_TO_BUILD" ;;
        host) case "$llvm_cv_target_arch" in
            x86)         TARGETS_TO_BUILD="X86 $TARGETS_TO_BUILD" ;;
            x86_64)      TARGETS_TO_BUILD="X86 $TARGETS_TO_BUILD" ;;
            Sparc)       TARGETS_TO_BUILD="Sparc $TARGETS_TO_BUILD" ;;
            PowerPC)     TARGETS_TO_BUILD="PowerPC $TARGETS_TO_BUILD" ;;
            Alpha)       TARGETS_TO_BUILD="Alpha $TARGETS_TO_BUILD" ;;
            ARM)         TARGETS_TO_BUILD="ARM $TARGETS_TO_BUILD" ;;
            Mips)        TARGETS_TO_BUILD="Mips $TARGETS_TO_BUILD" ;;
            CellSPU|SPU) TARGETS_TO_BUILD="CellSPU $TARGETS_TO_BUILD" ;;
            PIC16)       TARGETS_TO_BUILD="PIC16 $TARGETS_TO_BUILD" ;;
            XCore)       TARGETS_TO_BUILD="XCore $TARGETS_TO_BUILD" ;;
            MSP430)      TARGETS_TO_BUILD="MSP430 $TARGETS_TO_BUILD" ;;
            s390x)       TARGETS_TO_BUILD="SystemZ $TARGETS_TO_BUILD" ;;
            Blackfin)    TARGETS_TO_BUILD="Blackfin $TARGETS_TO_BUILD" ;;
            *)       AC_MSG_ERROR([Can not set target to build]) ;;
          esac ;;
        *) AC_MSG_ERROR([Unrecognized target $a_target]) ;;
      esac
  done
  ;;
esac
AC_SUBST(TARGETS_TO_BUILD,$TARGETS_TO_BUILD)

# Determine whether we are building LLVM support for the native architecture.
# If so, define LLVM_NATIVE_ARCH to that LLVM target.
for a_target in $TARGETS_TO_BUILD; do
  if test "$a_target" = "$LLVM_NATIVE_ARCH"; then
    LLVM_NATIVE_ARCHTARGET="${LLVM_NATIVE_ARCH}Target"
    AC_DEFINE_UNQUOTED(LLVM_NATIVE_ARCH,$LLVM_NATIVE_ARCHTARGET,
      [LLVM architecture name for the native architecture, if available])
  fi
done

# Build the LLVM_TARGET and LLVM_... macros for Targets.def and the individual
# target feature def files.
LLVM_ENUM_TARGETS=""
LLVM_ENUM_ASM_PRINTERS=""
LLVM_ENUM_ASM_PARSERS=""
LLVM_ENUM_DISASSEMBLERS=""
for target_to_build in $TARGETS_TO_BUILD; do
  LLVM_ENUM_TARGETS="LLVM_TARGET($target_to_build) $LLVM_ENUM_TARGETS"
  if test -f ${srcdir}/lib/Target/${target_to_build}/AsmPrinter/Makefile ; then
    LLVM_ENUM_ASM_PRINTERS="LLVM_ASM_PRINTER($target_to_build) $LLVM_ENUM_ASM_PRINTERS";
  fi
  if test -f ${srcdir}/lib/Target/${target_to_build}/AsmParser/Makefile ; then
    LLVM_ENUM_ASM_PARSERS="LLVM_ASM_PARSER($target_to_build) $LLVM_ENUM_ASM_PARSERS";
  fi
  if test -f ${srcdir}/lib/Target/${target_to_build}/Disassembler/Makefile ; then
    LLVM_ENUM_DISASSEMBLERS="LLVM_DISASSEMBLER($target_to_build) $LLVM_ENUM_DISASSEMBLERS";
  fi
done
AC_SUBST(LLVM_ENUM_TARGETS)
AC_SUBST(LLVM_ENUM_ASM_PRINTERS)
AC_SUBST(LLVM_ENUM_ASM_PARSERS)
AC_SUBST(LLVM_ENUM_DISASSEMBLERS)

dnl Prevent the CBackend from using printf("%a") for floating point so older
dnl C compilers that cannot deal with the 0x0p+0 hex floating point format
dnl can still compile the CBE's output
AC_ARG_ENABLE([cbe-printf-a],AS_HELP_STRING([--enable-cbe-printf-a],
  [Enable C Backend output with hex floating point via %a  (default is YES)]),,
  enableval=default)
case "$enableval" in
  yes) AC_SUBST(ENABLE_CBE_PRINTF_A,[1]) ;;
  no)  AC_SUBST(ENABLE_CBE_PRINTF_A,[0]) ;;
  default)  AC_SUBST(ENABLE_CBE_PRINTF_A,[1]) ;;
  *) AC_MSG_ERROR([Invalid setting for --enable-cbe-printf-a. Use "yes" or "no"]) ;;
esac
AC_DEFINE_UNQUOTED([ENABLE_CBE_PRINTF_A],$ENABLE_CBE_PRINTF_A,
                   [Define if CBE is enabled for printf %a output])

dnl Allow a specific llvm-gcc/llvm-g++ pair to be used with this LLVM config.
AC_ARG_WITH(llvmgccdir,
  AS_HELP_STRING([--with-llvmgccdir],
    [Specify location of llvm-gcc install dir (default searches PATH)]),,
    withval=default)
case "$withval" in
  default) WITH_LLVMGCCDIR=default ;;
  /* | [[A-Za-z]]:[[\\/]]*)      WITH_LLVMGCCDIR=$withval ;;
  *) AC_MSG_ERROR([Invalid path for --with-llvmgccdir. Provide full path]) ;;
esac

dnl Allow a specific llvm-gcc compiler to be used with this LLVM config.
AC_ARG_WITH(llvmgcc,
  AS_HELP_STRING([--with-llvmgcc],
    [Specify location of llvm-gcc driver (default searches PATH)]),
    LLVMGCC=$with_llvmgcc
      WITH_LLVMGCCDIR="",)

dnl Allow a specific llvm-g++ compiler to be used with this LLVM config.
AC_ARG_WITH(llvmgxx,
  AS_HELP_STRING([--with-llvmgxx],
    [Specify location of llvm-g++ driver (default searches PATH)]),
    LLVMGXX=$with_llvmgxx
    WITH_LLVMGCCDIR="",)

if test -n "$LLVMGCC"; then
   LLVMGCCCOMMAND="$LLVMGCC"
fi

if test -n "$LLVMGXX"; then
   LLVMGXXCOMMAND="$LLVMGXX"
fi

if test -n "$LLVMGCC" && test -z "$LLVMGXX"; then
   AC_MSG_ERROR([Invalid llvm-g++. Use --with-llvmgxx when --with-llvmgcc is used]);
fi

if test -n "$LLVMGXX" && test -z "$LLVMGCC"; then
   AC_MSG_ERROR([Invalid llvm-gcc. Use --with-llvmgcc when --with-llvmgxx is used]);
fi

dnl Override the option to use for optimized builds.
AC_ARG_WITH(optimize-option,
  AS_HELP_STRING([--with-optimize-option],
                 [Select the compiler options to use for optimized builds]),,
                 withval=default)
AC_MSG_CHECKING([optimization flags])
case "$withval" in
  default)
    case "$llvm_cv_os_type" in
    MingW) optimize_option=-O3 ;;
    *)     optimize_option=-O2 ;;
    esac ;;
  *) optimize_option="$withval" ;;
esac
AC_SUBST(OPTIMIZE_OPTION,$optimize_option)
AC_MSG_RESULT([$optimize_option])

dnl Specify extra build options
AC_ARG_WITH(extra-options,
  AS_HELP_STRING([--with-extra-options],
                 [Specify additional options to compile LLVM with]),,
                 withval=default)
case "$withval" in
  default) EXTRA_OPTIONS= ;;
  *) EXTRA_OPTIONS=$withval ;;
esac
AC_SUBST(EXTRA_OPTIONS,$EXTRA_OPTIONS)

dnl Allow specific bindings to be specified for building (or not)
AC_ARG_ENABLE([bindings],AS_HELP_STRING([--enable-bindings],
    [Build specific language bindings: all,auto,none,{binding-name} (default=auto)]),,
    enableval=default)
BINDINGS_TO_BUILD=""
case "$enableval" in
  yes | default | auto) BINDINGS_TO_BUILD="auto" ;;
  all ) BINDINGS_TO_BUILD="ocaml" ;;
  none | no) BINDINGS_TO_BUILD="" ;;
  *)for a_binding in `echo $enableval|sed -e 's/,/ /g' ` ; do
      case "$a_binding" in
        ocaml) BINDINGS_TO_BUILD="ocaml $BINDINGS_TO_BUILD" ;;
        *) AC_MSG_ERROR([Unrecognized binding $a_binding]) ;;
      esac
  done
  ;;
esac

dnl Allow the ocaml libdir to be overridden. This could go in a configure
dnl script for bindings/ocaml/configure, except that its auto value depends on
dnl OCAMLC, which is found here to support tests.
AC_ARG_WITH([ocaml-libdir],
  [AS_HELP_STRING([--with-ocaml-libdir],
    [Specify install location for ocaml bindings (default is stdlib)])],
  [],
  [withval=auto])
case "$withval" in
  auto) with_ocaml_libdir="$withval" ;;
  /* | [[A-Za-z]]:[[\\/]]*) with_ocaml_libdir="$withval" ;;
  *) AC_MSG_ERROR([Invalid path for --with-ocaml-libdir. Provide full path]) ;;
esac

AC_ARG_WITH(c-include-dirs,
  AS_HELP_STRING([--with-c-include-dirs],
    [Colon separated list of directories clang will search for headers]),,
    withval="")
AC_DEFINE_UNQUOTED(C_INCLUDE_DIRS,"$withval",
                   [Directories clang will search for headers])

AC_ARG_WITH(cxx-include-root,
  AS_HELP_STRING([--with-cxx-include-root],
    [Directory with the libstdc++ headers.]),,
    withval="")
AC_DEFINE_UNQUOTED(CXX_INCLUDE_ROOT,"$withval",
                   [Directory with the libstdc++ headers.])

AC_ARG_WITH(cxx-include-arch,
  AS_HELP_STRING([--with-cxx-include-arch],
    [Architecture of the libstdc++ headers.]),,
    withval="")
AC_DEFINE_UNQUOTED(CXX_INCLUDE_ARCH,"$withval",
                   [Arch the libstdc++ headers.])

AC_ARG_WITH(cxx-include-32bit-dir,
  AS_HELP_STRING([--with-cxx-include-32bit-dir],
    [32 bit multilib dir.]),,
    withval="")
AC_DEFINE_UNQUOTED(CXX_INCLUDE_32BIT_DIR,"$withval",
                   [32 bit multilib directory.])

AC_ARG_WITH(cxx-include-64bit-dir,
  AS_HELP_STRING([--with-cxx-include-64bit-dir],
    [64 bit multilib directory.]),,
    withval="")
AC_DEFINE_UNQUOTED(CXX_INCLUDE_64BIT_DIR,"$withval",
                   [64 bit multilib directory.])

dnl Allow linking of LLVM with GPLv3 binutils code.
AC_ARG_WITH(binutils-include,
  AS_HELP_STRING([--with-binutils-include],
    [Specify path to binutils/include/ containing plugin-api.h file for gold plugin.]),,
  withval=default)
case "$withval" in
  default) WITH_BINUTILS_INCDIR=default ;;
  /* | [[A-Za-z]]:[[\\/]]*)      WITH_BINUTILS_INCDIR=$withval ;;
  *) AC_MSG_ERROR([Invalid path for --with-binutils-include. Provide full path]) ;;
esac
if test "x$WITH_BINUTILS_INCDIR" != xdefault ; then
  AC_SUBST(BINUTILS_INCDIR,$WITH_BINUTILS_INCDIR)
  if test ! -f "$WITH_BINUTILS_INCDIR/plugin-api.h"; then
     echo "$WITH_BINUTILS_INCDIR/plugin-api.h"
     AC_MSG_ERROR([Invalid path to directory containing plugin-api.h.]);
  fi
fi

dnl --enable-libffi : check whether the user wants to turn off libffi:
AC_ARG_ENABLE(libffi,AS_HELP_STRING(
  --enable-libffi,[Check for the presence of libffi (default is YES)]),,
  enableval=yes)
case "$enableval" in
  yes) llvm_cv_enable_libffi="yes" ;;
  no)  llvm_cv_enable_libffi="no"  ;;
  *) AC_MSG_ERROR([Invalid setting for --enable-libffi. Use "yes" or "no"]) ;;
esac

dnl Only Windows needs dynamic libCompilerDriver to support plugins.
if test "$llvm_cv_os_type" = "Win32" ; then
   llvmc_dynamic="yes"
else
   llvmc_dynamic="no"
fi

dnl --enable-llvmc-dynamic : should LLVMC link libCompilerDriver dynamically?
AC_ARG_ENABLE(llvmc-dynamic,AS_HELP_STRING(
--enable-llvmc-dynamic,
[Link LLVMC dynamically (default is NO, unless on Win32)]),,
enableval=$llvmc_dynamic)
if test ${enableval} = "yes" && test "$ENABLE_PIC" -eq 1 ; then
   AC_SUBST(ENABLE_LLVMC_DYNAMIC,[[ENABLE_LLVMC_DYNAMIC=1]])
else
   AC_SUBST(ENABLE_LLVMC_DYNAMIC,[[]])
fi

dnl --enable-llvmc-dynamic-plugins : should LLVMC support dynamic plugins?
AC_ARG_ENABLE(llvmc-dynamic-plugins,AS_HELP_STRING(
--enable-llvmc-dynamic-plugins,
[Enable dynamic LLVMC plugins (default is YES)]),,
enableval=yes)
if test ${enableval} = "yes" ; then
   AC_SUBST(ENABLE_LLVMC_DYNAMIC_PLUGINS,[[ENABLE_LLVMC_DYNAMIC_PLUGINS=1]])
else
   AC_SUBST(ENABLE_LLVMC_DYNAMIC_PLUGINS,[[]])
fi

dnl===-----------------------------------------------------------------------===
dnl===
dnl=== SECTION 4: Check for programs we need and that they are the right version
dnl===
dnl===-----------------------------------------------------------------------===

dnl Check for compilation tools
AC_PROG_CPP
AC_PROG_CC(gcc)
AC_PROG_CXX(g++)

AC_PROG_NM
AC_SUBST(NM)

dnl Check for the tools that the makefiles require
AC_CHECK_GNU_MAKE
AC_PROG_LN_S
AC_PATH_PROG(CMP, [cmp], [cmp])
AC_PATH_PROG(CP, [cp], [cp])
AC_PATH_PROG(DATE, [date], [date])
AC_PATH_PROG(FIND, [find], [find])
AC_PATH_PROG(GREP, [grep], [grep])
AC_PATH_PROG(MKDIR,[mkdir],[mkdir])
AC_PATH_PROG(MV,   [mv],   [mv])
AC_PROG_RANLIB
AC_PATH_PROG(RM,   [rm],   [rm])
AC_PATH_PROG(SED,  [sed],  [sed])
AC_PATH_PROG(TAR,  [tar],  [gtar])
AC_PATH_PROG(BINPWD,[pwd],  [pwd])

dnl Looking for misc. graph plotting software
AC_PATH_PROG(GRAPHVIZ, [Graphviz], [echo Graphviz])
if test "$GRAPHVIZ" != "echo Graphviz" ; then
  AC_DEFINE([HAVE_GRAPHVIZ],[1],[Define if the Graphviz program is available])
  dnl If we're targeting for mingw we should emit windows paths, not msys
  if test "$llvm_cv_os_type" = "MingW" ; then
    GRAPHVIZ=`echo $GRAPHVIZ | sed 's/^\/\([[A-Za-z]]\)\//\1:\//' `
  fi
  AC_DEFINE_UNQUOTED([LLVM_PATH_GRAPHVIZ],"$GRAPHVIZ${EXEEXT}",
   [Define to path to Graphviz program if found or 'echo Graphviz' otherwise])
fi
AC_PATH_PROG(DOT, [dot], [echo dot])
if test "$DOT" != "echo dot" ; then
  AC_DEFINE([HAVE_DOT],[1],[Define if the dot program is available])
  dnl If we're targeting for mingw we should emit windows paths, not msys
  if test "$llvm_cv_os_type" = "MingW" ; then
    DOT=`echo $DOT | sed 's/^\/\([[A-Za-z]]\)\//\1:\//' `
  fi
  AC_DEFINE_UNQUOTED([LLVM_PATH_DOT],"$DOT${EXEEXT}",
   [Define to path to dot program if found or 'echo dot' otherwise])
fi
AC_PATH_PROG(FDP, [fdp], [echo fdp])
if test "$FDP" != "echo fdp" ; then
  AC_DEFINE([HAVE_FDP],[1],[Define if the neat program is available])
  dnl If we're targeting for mingw we should emit windows paths, not msys
  if test "$llvm_cv_os_type" = "MingW" ; then
    FDP=`echo $FDP | sed 's/^\/\([[A-Za-z]]\)\//\1:\//' `
  fi
  AC_DEFINE_UNQUOTED([LLVM_PATH_FDP],"$FDP${EXEEXT}",
   [Define to path to fdp program if found or 'echo fdp' otherwise])
fi
AC_PATH_PROG(NEATO, [neato], [echo neato])
if test "$NEATO" != "echo neato" ; then
  AC_DEFINE([HAVE_NEATO],[1],[Define if the neat program is available])
  dnl If we're targeting for mingw we should emit windows paths, not msys
  if test "$llvm_cv_os_type" = "MingW" ; then
    NEATO=`echo $NEATO | sed 's/^\/\([[A-Za-z]]\)\//\1:\//' `
  fi
  AC_DEFINE_UNQUOTED([LLVM_PATH_NEATO],"$NEATO${EXEEXT}",
   [Define to path to neato program if found or 'echo neato' otherwise])
fi
AC_PATH_PROG(TWOPI, [twopi], [echo twopi])
if test "$TWOPI" != "echo twopi" ; then
  AC_DEFINE([HAVE_TWOPI],[1],[Define if the neat program is available])
  dnl If we're targeting for mingw we should emit windows paths, not msys
  if test "$llvm_cv_os_type" = "MingW" ; then
    TWOPI=`echo $TWOPI | sed 's/^\/\([[A-Za-z]]\)\//\1:\//' `
  fi
  AC_DEFINE_UNQUOTED([LLVM_PATH_TWOPI],"$TWOPI${EXEEXT}",
   [Define to path to twopi program if found or 'echo twopi' otherwise])
fi
AC_PATH_PROG(CIRCO, [circo], [echo circo])
if test "$CIRCO" != "echo circo" ; then
  AC_DEFINE([HAVE_CIRCO],[1],[Define if the neat program is available])
  dnl If we're targeting for mingw we should emit windows paths, not msys
  if test "$llvm_cv_os_type" = "MingW" ; then
    CIRCO=`echo $CIRCO | sed 's/^\/\([[A-Za-z]]\)\//\1:\//' `
  fi
  AC_DEFINE_UNQUOTED([LLVM_PATH_CIRCO],"$CIRCO${EXEEXT}",
   [Define to path to circo program if found or 'echo circo' otherwise])
fi
AC_PATH_PROGS(GV, [gv gsview32], [echo gv])
if test "$GV" != "echo gv" ; then
  AC_DEFINE([HAVE_GV],[1],[Define if the gv program is available])
  dnl If we're targeting for mingw we should emit windows paths, not msys
  if test "$llvm_cv_os_type" = "MingW" ; then
    GV=`echo $GV | sed 's/^\/\([[A-Za-z]]\)\//\1:\//' `
  fi
  AC_DEFINE_UNQUOTED([LLVM_PATH_GV],"$GV${EXEEXT}",
   [Define to path to gv program if found or 'echo gv' otherwise])
fi
AC_PATH_PROG(DOTTY, [dotty], [echo dotty])
if test "$DOTTY" != "echo dotty" ; then
  AC_DEFINE([HAVE_DOTTY],[1],[Define if the dotty program is available])
  dnl If we're targeting for mingw we should emit windows paths, not msys
  if test "$llvm_cv_os_type" = "MingW" ; then
    DOTTY=`echo $DOTTY | sed 's/^\/\([[A-Za-z]]\)\//\1:\//' `
  fi
  AC_DEFINE_UNQUOTED([LLVM_PATH_DOTTY],"$DOTTY${EXEEXT}",
   [Define to path to dotty program if found or 'echo dotty' otherwise])
fi

dnl Look for a sufficiently recent version of Perl.
LLVM_PROG_PERL([5.006])
AC_SUBST(PERL)
if test x"$PERL" = xnone; then
   AC_SUBST(HAVE_PERL,0)
   AC_MSG_ERROR([perl is required but was not found, please install it])
else
   AC_SUBST(HAVE_PERL,1)
fi

dnl Find the install program
AC_PROG_INSTALL

dnl Checks for documentation and testing tools that we can do without. If these
dnl are not found then they are set to "true" which always succeeds but does
dnl nothing. This just lets the build output show that we could have done
dnl something if the tool was available.
AC_PATH_PROG(BZIP2, [bzip2])
AC_PATH_PROG(DOXYGEN, [doxygen])
AC_PATH_PROG(GROFF, [groff])
AC_PATH_PROG(GZIP, [gzip])
AC_PATH_PROG(POD2HTML, [pod2html])
AC_PATH_PROG(POD2MAN, [pod2man])
AC_PATH_PROG(RUNTEST, [runtest])
DJ_AC_PATH_TCLSH
AC_PATH_PROG(ZIP, [zip])
AC_PATH_PROGS(OCAMLC, [ocamlc])
AC_PATH_PROGS(OCAMLOPT, [ocamlopt])
AC_PATH_PROGS(OCAMLDEP, [ocamldep])
AC_PATH_PROGS(OCAMLDOC, [ocamldoc])
AC_PATH_PROGS(GAS, [gas as])

dnl Determine whether the linker supports the -R option.
AC_LINK_USE_R

dnl Determine whether the linker supports the -export-dynamic option.
AC_LINK_EXPORT_DYNAMIC

dnl Check for libtool and the library that has dlopen function (which must come
dnl before the AC_PROG_LIBTOOL check in order to enable dlopening libraries with
dnl libtool).
AC_LIBTOOL_DLOPEN
AC_LIB_LTDL
AC_PROG_LIBTOOL

if test "$lt_cv_dlopen_self" = "yes" ; then
  AC_DEFINE([CAN_DLOPEN_SELF],[1],
              [Define if dlopen(0) will open the symbols of the program])
fi


if test "$WITH_LLVMGCCDIR" = "default" ; then
  LLVMGCC="llvm-gcc${EXEEXT}"
  LLVMGXX="llvm-g++${EXEEXT}"
  LLVMGCCCOMMAND="$LLVMGCC"
  LLVMGXXCOMMAND="$LLVMGXX"
  AC_SUBST(LLVMGCCCOMMAND,$LLVMGCCCOMMAND)
  AC_SUBST(LLVMGXXCOMMAND,$LLVMGXXCOMMAND)
  AC_PATH_PROG(LLVMGCC, $LLVMGCC, [])
  AC_PATH_PROG(LLVMGXX, $LLVMGXX, [])
else
  if test -z "$LLVMGCC"; then
    LLVMGCC="$WITH_LLVMGCCDIR/bin/llvm-gcc${EXEEXT}"
    LLVMGCCCOMMAND="$LLVMGCC"
  fi
  if test -z "$LLVMGXX"; then
    LLVMGXX="$WITH_LLVMGCCDIR/bin/llvm-g++${EXEEXT}"
    LLVMGXXCOMMAND="$LLVMGXX"
  fi

  AC_SUBST(LLVMGCC,$LLVMGCC)
  AC_SUBST(LLVMGXX,$LLVMGXX)
  AC_SUBST(LLVMGCCCOMMAND,$LLVMGCCCOMMAND)
  AC_SUBST(LLVMGXXCOMMAND,$LLVMGXXCOMMAND)
fi


AC_MSG_CHECKING([tool compatibility])

dnl Ensure that compilation tools are GCC or a GNU compatible compiler such as
dnl ICC; we use GCC specific options in the makefiles so the compiler needs
dnl to support those options.
dnl "icc" emits gcc signatures
dnl "icc -no-gcc" emits no gcc signature BUT is still compatible
ICC=no
IXX=no
case $CC in
  icc*|icpc*)
    ICC=yes
    IXX=yes
    ;;
   *)
    ;;
esac

if test "$GCC" != "yes" && test "$ICC" != "yes"
then
  AC_MSG_ERROR([gcc|icc required but not found])
fi

dnl Ensure that compilation tools are GCC; we use GCC specific extensions
if test "$GXX" != "yes" && test "$IXX" != "yes"
then
  AC_MSG_ERROR([g++|icc required but not found])
fi

dnl Verify that GCC is version 3.0 or higher
if test "$GCC" = "yes"
then
  AC_COMPILE_IFELSE([[#if !defined(__GNUC__) || __GNUC__ < 3
#error Unsupported GCC version
#endif
]], [], [AC_MSG_ERROR([gcc 3.x required, but you have a lower version])])
fi

dnl Check for GNU Make.  We use its extensions, so don't build without it
if test -z "$llvm_cv_gnu_make_command"
then
  AC_MSG_ERROR([GNU Make required but not found])
fi

dnl Tool compatibility is okay if we make it here.
AC_MSG_RESULT([ok])

dnl Check optional compiler flags. 
AC_MSG_CHECKING([optional compiler flags])
CXX_FLAG_CHECK(NO_VARIADIC_MACROS, [-Wno-variadic-macros])
CXX_FLAG_CHECK(NO_MISSING_FIELD_INITIALIZERS, [-Wno-missing-field-initializers])
AC_MSG_RESULT([$NO_VARIADIC_MACROS $NO_MISSING_FIELD_INITIALIZERS])

dnl===-----------------------------------------------------------------------===
dnl===
dnl=== SECTION 5: Check for libraries
dnl===
dnl===-----------------------------------------------------------------------===

AC_CHECK_LIB(m,sin)
if test "$llvm_cv_os_type" = "MingW" ; then
  AC_CHECK_LIB(imagehlp, main)
  AC_CHECK_LIB(psapi, main)
fi

dnl dlopen() is required for plugin support.
AC_SEARCH_LIBS(dlopen,dl,AC_DEFINE([HAVE_DLOPEN],[1],
               [Define if dlopen() is available on this platform.]),
               AC_MSG_WARN([dlopen() not found - disabling plugin support]))

dnl libffi is optional; used to call external functions from the interpreter
if test "$llvm_cv_enable_libffi" = "yes" ; then
  AC_SEARCH_LIBS(ffi_call,ffi,AC_DEFINE([HAVE_FFI_CALL],[1],
                 [Define if libffi is available on this platform.]),
                 AC_MSG_WARN([libffi not found - disabling external calls from interpreter]))
fi

dnl mallinfo is optional; the code can compile (minus features) without it
AC_SEARCH_LIBS(mallinfo,malloc,AC_DEFINE([HAVE_MALLINFO],[1],
               [Define if mallinfo() is available on this platform.]))

dnl pthread locking functions are optional - but llvm will not be thread-safe
dnl without locks.
if test "$ENABLE_THREADS" -eq 1 ; then
  AC_CHECK_LIB(pthread, pthread_mutex_init)
  AC_SEARCH_LIBS(pthread_mutex_lock,pthread,
                 AC_DEFINE([HAVE_PTHREAD_MUTEX_LOCK],[1],
                           [Have pthread_mutex_lock]))
  AC_SEARCH_LIBS(pthread_rwlock_init,pthread,
                 AC_DEFINE([HAVE_PTHREAD_RWLOCK_INIT],[1],
                 [Have pthread_rwlock_init]))
  AC_SEARCH_LIBS(pthread_getspecific,pthread,
                 AC_DEFINE([HAVE_PTHREAD_GETSPECIFIC],[1],
                 [Have pthread_getspecific]))
fi

dnl Allow extra x86-disassembler library
AC_ARG_WITH(udis86,
  AS_HELP_STRING([--with-udis86=<path>],
    [Use udis86 external x86 disassembler library]),
    [
      AC_SUBST(USE_UDIS86, [1])
      case "$withval" in
        /usr/lib|yes) ;;
        *) LDFLAGS="$LDFLAGS -L${withval}" ;;
      esac
      AC_CHECK_LIB(udis86, ud_init, [], [
        echo "Error! You need to have libudis86 around."
        exit -1
      ])
    ],
    AC_SUBST(USE_UDIS86, [0]))
AC_DEFINE_UNQUOTED([USE_UDIS86],$USE_UDIS86,
                   [Define if use udis86 library])

dnl Allow OProfile support for JIT output.
AC_ARG_WITH(oprofile,
  AS_HELP_STRING([--with-oprofile=<prefix>],
    [Tell OProfile >= 0.9.4 how to symbolize JIT output]),
    [
      AC_SUBST(USE_OPROFILE, [1])
      case "$withval" in
        /usr|yes) llvm_cv_oppath=/usr/lib/oprofile ;;
        no) llvm_cv_oppath=
            AC_SUBST(USE_OPROFILE, [0]) ;;
        *) llvm_cv_oppath="${withval}/lib/oprofile"
           CPPFLAGS="-I${withval}/include";;
      esac
      if test -n "$llvm_cv_oppath" ; then
        LIBS="$LIBS -L${llvm_cv_oppath} -Wl,-rpath,${llvm_cv_oppath}"
        dnl Work around http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=537744:
        dnl libbfd is not included properly in libopagent in some Debian
        dnl versions.  If libbfd isn't found at all, we assume opagent works
        dnl anyway.
        AC_SEARCH_LIBS(bfd_init, bfd, [], [])
        AC_SEARCH_LIBS(op_open_agent, opagent, [], [
          echo "Error! You need to have libopagent around."
          exit -1
        ])
        AC_CHECK_HEADER([opagent.h], [], [
          echo "Error! You need to have opagent.h around."
          exit -1
          ])
      fi
    ],
    [
      AC_SUBST(USE_OPROFILE, [0])
    ])
AC_DEFINE_UNQUOTED([USE_OPROFILE],$USE_OPROFILE,
                   [Define if we have the oprofile JIT-support library])

dnl===-----------------------------------------------------------------------===
dnl===
dnl=== SECTION 6: Check for header files
dnl===
dnl===-----------------------------------------------------------------------===

dnl First, use autoconf provided macros for specific headers that we need
dnl We don't check for ancient stuff or things that are guaranteed to be there
dnl by the C++ standard. We always use the <cfoo> versions of <foo.h> C headers.
dnl Generally we're looking for POSIX headers.
AC_HEADER_DIRENT
AC_HEADER_MMAP_ANONYMOUS
AC_HEADER_STAT
AC_HEADER_STDC
AC_HEADER_SYS_WAIT
AC_HEADER_TIME

AC_CHECK_HEADERS([dlfcn.h execinfo.h fcntl.h inttypes.h limits.h link.h])
AC_CHECK_HEADERS([malloc.h setjmp.h signal.h stdint.h termios.h unistd.h])
AC_CHECK_HEADERS([utime.h windows.h])
AC_CHECK_HEADERS([sys/mman.h sys/param.h sys/resource.h sys/time.h])
AC_CHECK_HEADERS([sys/types.h sys/ioctl.h malloc/malloc.h mach/mach.h])
if test "$ENABLE_THREADS" -eq 1 ; then
  AC_CHECK_HEADERS(pthread.h,
                   AC_SUBST(HAVE_PTHREAD, 1),
                   AC_SUBST(HAVE_PTHREAD, 0))
else
  AC_SUBST(HAVE_PTHREAD, 0)
fi

dnl Try to find ffi.h.
if test "$llvm_cv_enable_libffi" = "yes" ; then
  AC_CHECK_HEADERS([ffi.h ffi/ffi.h])
fi

dnl===-----------------------------------------------------------------------===
dnl===
dnl=== SECTION 7: Check for types and structures
dnl===
dnl===-----------------------------------------------------------------------===

AC_HUGE_VAL_CHECK
AC_TYPE_PID_T
AC_TYPE_SIZE_T
AC_TYPE_SIGNAL
AC_STRUCT_TM
AC_CHECK_TYPES([int64_t],,AC_MSG_ERROR([Type int64_t required but not found]))
AC_CHECK_TYPES([uint64_t],,
         AC_CHECK_TYPES([u_int64_t],,
         AC_MSG_ERROR([Type uint64_t or u_int64_t required but not found])))

dnl===-----------------------------------------------------------------------===
dnl===
dnl=== SECTION 8: Check for specific functions needed
dnl===
dnl===-----------------------------------------------------------------------===

AC_CHECK_FUNCS([backtrace ceilf floorf roundf rintf nearbyintf getcwd ])
AC_CHECK_FUNCS([powf fmodf strtof round ])
AC_CHECK_FUNCS([getpagesize getrusage getrlimit setrlimit gettimeofday ])
AC_CHECK_FUNCS([isatty mkdtemp mkstemp ])
AC_CHECK_FUNCS([mktemp realpath sbrk setrlimit strdup ])
AC_CHECK_FUNCS([strerror strerror_r strerror_s setenv ])
AC_CHECK_FUNCS([strtoll strtoq sysconf malloc_zone_statistics ])
AC_CHECK_FUNCS([setjmp longjmp sigsetjmp siglongjmp])
AC_C_PRINTF_A
dnl FIXME: This is no longer used, please remove (but test)!!!
AC_FUNC_ALLOCA
AC_FUNC_RAND48

dnl Check for variations in the Standard C++ library and STL. These macros are
dnl provided by LLVM in the autoconf/m4 directory.
AC_CXX_HAVE_STD_ITERATOR
AC_CXX_HAVE_BI_ITERATOR
AC_CXX_HAVE_FWD_ITERATOR
AC_FUNC_ISNAN
AC_FUNC_ISINF

dnl Check for mmap support.We also need to know if /dev/zero is required to
dnl be opened for allocating RWX memory.
dnl Make sure we aren't attempting to configure for an unknown system
if test "$llvm_cv_platform_type" = "Unix" ; then
  AC_FUNC_MMAP
  AC_FUNC_MMAP_FILE
  AC_NEED_DEV_ZERO_FOR_MMAP

  if test "$ac_cv_func_mmap_fixed_mapped" = "no"
  then
    AC_MSG_WARN([mmap() of a fixed address required but not supported])
  fi
  if test "$ac_cv_func_mmap_file" = "no"
  then
    AC_MSG_WARN([mmap() of files required but not found])
  fi
fi

dnl atomic builtins are required for threading support.
AC_MSG_CHECKING(for GCC atomic builtins)
AC_LINK_IFELSE(
  AC_LANG_SOURCE(
    [[int main() {
        volatile unsigned long val = 1;
        __sync_synchronize();
        __sync_val_compare_and_swap(&val, 1, 0);
        __sync_add_and_fetch(&val, 1);
        __sync_sub_and_fetch(&val, 1);
        return 0;
      }
    ]]),
  AC_MSG_RESULT(yes)
  AC_DEFINE(LLVM_MULTITHREADED, 1, Build multithreading support into LLVM),
  AC_MSG_RESULT(no)
  AC_DEFINE(LLVM_MULTITHREADED, 0, Build multithreading support into LLVM)
  AC_MSG_WARN([LLVM will be built thread-unsafe because atomic builtins are missing]))


dnl===-----------------------------------------------------------------------===
dnl===
dnl=== SECTION 9: Additional checks, variables, etc.
dnl===
dnl===-----------------------------------------------------------------------===

dnl Handle 32-bit linux systems running a 64-bit kernel.
dnl This has to come after section 4 because it invokes the compiler.
if test "$llvm_cv_os_type" = "Linux" -a "$llvm_cv_target_arch" = "x86_64" ; then
  AC_IS_LINUX_MIXED
  if test "$llvm_cv_linux_mixed" = "yes"; then
    llvm_cv_target_arch="x86"
    ARCH="x86"
  fi
fi

dnl Check, whether __dso_handle is present
AC_CHECK_FUNCS([__dso_handle])

dnl See if the llvm-gcc executable can compile to LLVM assembly
AC_CACHE_CHECK([whether llvm-gcc is sane],[llvm_cv_llvmgcc_sanity],
[llvm_cv_llvmgcc_sanity="no"
if test -x "$LLVMGCC" ; then
  cp /dev/null conftest.c
  "$LLVMGCC" -emit-llvm -S -o - conftest.c | \
      grep 'target datalayout =' > /dev/null 2>&1
  if test $? -eq 0 ; then
    llvm_cv_llvmgcc_sanity="yes"
  fi
  rm conftest.c
fi])

dnl Since we have a sane llvm-gcc, identify it and its sub-tools
if test "$llvm_cv_llvmgcc_sanity" = "yes" ; then
  AC_MSG_CHECKING([llvm-gcc component support])
  llvmcc1path=`"$LLVMGCC" --print-prog-name=cc1`
  AC_SUBST(LLVMCC1,$llvmcc1path)
  llvmcc1pluspath=`"$LLVMGCC" --print-prog-name=cc1plus`
  AC_SUBST(LLVMCC1PLUS,$llvmcc1pluspath)
  llvmgccdir=`echo "$llvmcc1path" | sed 's,/libexec/.*,,'`
  AC_SUBST(LLVMGCCDIR,$llvmgccdir)
  llvmgcclibexec=`echo "$llvmcc1path" | sed 's,/cc1,,'`
  AC_SUBST(LLVMGCCLIBEXEC,$llvmgcclibexec)
  llvmgccversion=[`"$LLVMGCC" -dumpversion 2>&1 | sed 's/^\([0-9.]*\).*/\1/'`]
  llvmgccmajvers=[`echo $llvmgccversion | sed 's/^\([0-9]\).*/\1/'`]
  AC_SUBST(LLVMGCC_VERSION,$llvmgccversion)
  AC_SUBST(LLVMGCC_MAJVERS,$llvmgccmajvers)
  llvmgcclangs=[`"$LLVMGCC" -v --help 2>&1 | grep '^Configured with:' | sed 's/^.*--enable-languages=\([^ ]*\).*/\1/'`]
  AC_SUBST(LLVMGCC_LANGS,$llvmgcclangs)
  AC_MSG_RESULT([ok])
fi

dnl Propagate the shared library extension that the libltdl checks did to
dnl the Makefiles so we can use it there too
AC_SUBST(SHLIBEXT,$libltdl_cv_shlibext)

# Translate the various configuration directories and other basic
# information into substitutions that will end up in Makefile.config.in
# that these configured values can be used by the makefiles
if test "${prefix}" = "NONE" ; then
  prefix="/usr/local"
fi
eval LLVM_PREFIX="${prefix}";
eval LLVM_BINDIR="${prefix}/bin";
eval LLVM_LIBDIR="${prefix}/lib";
eval LLVM_DATADIR="${prefix}/share/llvm";
eval LLVM_DOCSDIR="${prefix}/docs/llvm";
eval LLVM_ETCDIR="${prefix}/etc/llvm";
eval LLVM_INCLUDEDIR="${prefix}/include";
eval LLVM_INFODIR="${prefix}/info";
eval LLVM_MANDIR="${prefix}/man";
LLVM_CONFIGTIME=`date`
AC_SUBST(LLVM_PREFIX)
AC_SUBST(LLVM_BINDIR)
AC_SUBST(LLVM_LIBDIR)
AC_SUBST(LLVM_DATADIR)
AC_SUBST(LLVM_DOCSDIR)
AC_SUBST(LLVM_ETCDIR)
AC_SUBST(LLVM_INCLUDEDIR)
AC_SUBST(LLVM_INFODIR)
AC_SUBST(LLVM_MANDIR)
AC_SUBST(LLVM_CONFIGTIME)

# Place the various directores into the config.h file as #defines so that we
# can know about the installation paths within LLVM.
AC_DEFINE_UNQUOTED(LLVM_PREFIX,"$LLVM_PREFIX",
                   [Installation prefix directory])
AC_DEFINE_UNQUOTED(LLVM_BINDIR, "$LLVM_BINDIR",
                   [Installation directory for binary executables])
AC_DEFINE_UNQUOTED(LLVM_LIBDIR, "$LLVM_LIBDIR",
                   [Installation directory for libraries])
AC_DEFINE_UNQUOTED(LLVM_DATADIR, "$LLVM_DATADIR",
                   [Installation directory for data files])
AC_DEFINE_UNQUOTED(LLVM_DOCSDIR, "$LLVM_DOCSDIR",
                   [Installation directory for documentation])
AC_DEFINE_UNQUOTED(LLVM_ETCDIR, "$LLVM_ETCDIR",
                   [Installation directory for config files])
AC_DEFINE_UNQUOTED(LLVM_INCLUDEDIR, "$LLVM_INCLUDEDIR",
                   [Installation directory for include files])
AC_DEFINE_UNQUOTED(LLVM_INFODIR, "$LLVM_INFODIR",
                   [Installation directory for .info files])
AC_DEFINE_UNQUOTED(LLVM_MANDIR, "$LLVM_MANDIR",
                   [Installation directory for man pages])
AC_DEFINE_UNQUOTED(LLVM_CONFIGTIME, "$LLVM_CONFIGTIME",
                   [Time at which LLVM was configured])
AC_DEFINE_UNQUOTED(LLVM_HOSTTRIPLE, "$host",
                   [Host triple we were built on])

# Determine which bindings to build.
if test "$BINDINGS_TO_BUILD" = auto ; then
  BINDINGS_TO_BUILD=""
  if test "x$OCAMLC" != x -a "x$OCAMLDEP" != x ; then
    BINDINGS_TO_BUILD="ocaml $BINDINGS_TO_BUILD"
  fi
fi
AC_SUBST(BINDINGS_TO_BUILD,$BINDINGS_TO_BUILD)

# This isn't really configurey, but it avoids having to repeat the list in
# other files.
AC_SUBST(ALL_BINDINGS,ocaml)

# Do any work necessary to ensure that bindings have what they need.
binding_prereqs_failed=0
for a_binding in $BINDINGS_TO_BUILD ; do
  case "$a_binding" in
  ocaml)
    if test "x$OCAMLC" = x ; then
      AC_MSG_WARN([--enable-bindings=ocaml specified, but ocamlc not found. Try configure OCAMLC=/path/to/ocamlc])
      binding_prereqs_failed=1
    fi
    if test "x$OCAMLDEP" = x ; then
      AC_MSG_WARN([--enable-bindings=ocaml specified, but ocamldep not found. Try configure OCAMLDEP=/path/to/ocamldep])
      binding_prereqs_failed=1
    fi
    if test "x$OCAMLOPT" = x ; then
      AC_MSG_WARN([--enable-bindings=ocaml specified, but ocamlopt not found. Try configure OCAMLOPT=/path/to/ocamlopt])
      dnl ocamlopt is optional!
    fi
    if test "x$with_ocaml_libdir" != xauto ; then
      AC_SUBST(OCAML_LIBDIR,$with_ocaml_libdir)
    else
      ocaml_stdlib="`"$OCAMLC" -where`"
      if test "$LLVM_PREFIX" '<' "$ocaml_stdlib" -a "$ocaml_stdlib" '<' "$LLVM_PREFIX~"
      then
        # ocaml stdlib is beneath our prefix; use stdlib
        AC_SUBST(OCAML_LIBDIR,$ocaml_stdlib)
      else
        # ocaml stdlib is outside our prefix; use libdir/ocaml
        AC_SUBST(OCAML_LIBDIR,$LLVM_LIBDIR/ocaml)
      fi
    fi
    ;;
  esac
done
if test "$binding_prereqs_failed" = 1 ; then
  AC_MSG_ERROR([Prequisites for bindings not satisfied. Fix them or use configure --disable-bindings.])
fi

dnl Determine whether the compiler supports -fvisibility-inlines-hidden.
AC_CXX_USE_VISIBILITY_INLINES_HIDDEN

dnl Determine linker rpath flag
if test "$llvm_cv_link_use_r" = "yes" ; then
  RPATH="-Wl,-R"
else
  RPATH="-Wl,-rpath"
fi
AC_SUBST(RPATH)

dnl Determine linker rdynamic flag
if test "$llvm_cv_link_use_export_dynamic" = "yes" ; then
  RDYNAMIC="-Wl,-export-dynamic"
else
  RDYNAMIC=""
fi
AC_SUBST(RDYNAMIC)

dnl===-----------------------------------------------------------------------===
dnl===
dnl=== SECTION 10: Specify the output files and generate it
dnl===
dnl===-----------------------------------------------------------------------===

dnl Configure header files
dnl WARNING: dnl If you add or remove any of the following config headers, then
dnl you MUST also update Makefile.rules so that the variable FilesToConfig
dnl contains the same list of files as AC_CONFIG_HEADERS below. This ensures the
dnl files can be updated automatically when their *.in sources change.
AC_CONFIG_HEADERS([include/llvm/Config/config.h])
AC_CONFIG_FILES([include/llvm/Config/Targets.def])
AC_CONFIG_FILES([include/llvm/Config/AsmPrinters.def])
AC_CONFIG_FILES([include/llvm/Config/AsmParsers.def])
AC_CONFIG_FILES([include/llvm/Config/Disassemblers.def])
AC_CONFIG_HEADERS([include/llvm/System/DataTypes.h])

dnl Configure the makefile's configuration data
AC_CONFIG_FILES([Makefile.config])

dnl Configure the RPM spec file for LLVM
AC_CONFIG_FILES([llvm.spec])

dnl Configure doxygen's configuration file
AC_CONFIG_FILES([docs/doxygen.cfg])

dnl Configure llvmc's Base plugin
AC_CONFIG_FILES([tools/llvmc/plugins/Base/Base.td])

dnl Do the first stage of configuration for llvm-config.in.
AC_CONFIG_FILES([tools/llvm-config/llvm-config.in])

dnl Do special configuration of Makefiles
AC_CONFIG_COMMANDS([setup],,[llvm_src="${srcdir}"])
AC_CONFIG_MAKEFILE(Makefile)
AC_CONFIG_MAKEFILE(Makefile.common)
AC_CONFIG_MAKEFILE(examples/Makefile)
AC_CONFIG_MAKEFILE(lib/Makefile)
AC_CONFIG_MAKEFILE(runtime/Makefile)
AC_CONFIG_MAKEFILE(test/Makefile)
AC_CONFIG_MAKEFILE(test/Makefile.tests)
AC_CONFIG_MAKEFILE(unittests/Makefile)
AC_CONFIG_MAKEFILE(tools/Makefile)
AC_CONFIG_MAKEFILE(utils/Makefile)
AC_CONFIG_MAKEFILE(projects/Makefile)
AC_CONFIG_MAKEFILE(bindings/Makefile)
AC_CONFIG_MAKEFILE(bindings/ocaml/Makefile.ocaml)

dnl Finally, crank out the output
AC_OUTPUT