libgomp/configure.ac - gcc - Git at Google

 # Process this file with autoconf to produce a configure script, like so:
 # aclocal -I ../config && autoconf && autoheader && automake

 AC_INIT([GNU Offloading and Multi Processing Runtime Library], 1.0,,[libgomp])
 AC_CONFIG_HEADER(config.h)

 # -------
 # Options
 # -------

 AC_MSG_CHECKING([for --enable-version-specific-runtime-libs])
 LIBGOMP_ENABLE(version-specific-runtime-libs, no, ,
    [Specify that runtime libraries should be installed in a compiler-specific directory],
    permit yes|no)
 AC_MSG_RESULT($enable_version_specific_runtime_libs)

 # We would like our source tree to be readonly. However when releases or
 # pre-releases are generated, the flex/bison generated files as well as the
 # various formats of manuals need to be included along with the rest of the
 # sources.  Therefore we have --enable-generated-files-in-srcdir to do
 # just that.
 AC_MSG_CHECKING([for --enable-generated-files-in-srcdir])
 LIBGOMP_ENABLE(generated-files-in-srcdir, no, ,
    [put copies of generated files in source dir intended for creating source
     tarballs for users without texinfo bison or flex.],
    permit yes|no)
 AC_MSG_RESULT($enable_generated_files_in_srcdir)
 AM_CONDITIONAL(GENINSRC, test "$enable_generated_files_in_srcdir" = yes)


 # -------
 # -------

 # Gets build, host, target, *_vendor, *_cpu, *_os, etc.
 #
 # You will slowly go insane if you do not grok the following fact:  when
 # building this library, the top-level /target/ becomes the library's /host/.
 #
 # configure then causes --target to default to --host, exactly like any
 # other package using autoconf.  Therefore, 'target' and 'host' will
 # always be the same.  This makes sense both for native and cross compilers
 # just think about it for a little while.  :-)
 #
 # Also, if this library is being configured as part of a cross compiler, the
 # top-level configure script will pass the "real" host as $with_cross_host.
 #
 # Do not delete or change the following two lines.  For why, see
 # http://gcc.gnu.org/ml/libstdc++/2003-07/msg00451.html
 AC_CANONICAL_SYSTEM
 target_alias=${target_alias-$host_alias}

 # Sets up automake.  Must come after AC_CANONICAL_SYSTEM.  Each of the
 # following is magically included in AUTOMAKE_OPTIONS in each Makefile.am.
 #  1.9.0:  minimum required version
 #  no-define:  PACKAGE and VERSION will not be #define'd in config.h (a bunch
 #              of other PACKAGE_* variables will, however, and there's nothing
 #              we can do about that; they come from AC_INIT).
 #  foreign:  we don't follow the normal rules for GNU packages (no COPYING
 #            file in the top srcdir, etc, etc), so stop complaining.
 #  no-dist:  we don't want 'dist' and related rules.
 #  -Wall:  turns on all automake warnings...
 #  -Wno-portability:  ...except this one, since GNU make is required.
 #  -Wno-override: ... and this one, since we do want this in testsuite.
 AM_INIT_AUTOMAKE([1.9.0 foreign no-dist -Wall -Wno-portability -Wno-override])
 AM_ENABLE_MULTILIB(, ..)

 GCC_WITH_TOOLEXECLIBDIR

 # Calculate toolexeclibdir
 # Also toolexecdir, though it's only used in toolexeclibdir
 case ${enable_version_specific_runtime_libs} in
   yes)
     # Need the gcc compiler version to know where to install libraries
     # and header files if --enable-version-specific-runtime-libs option
     # is selected.
     toolexecdir='$(libdir)/gcc/$(target_alias)'
     toolexeclibdir='$(toolexecdir)/$(gcc_version)$(MULTISUBDIR)'
     ;;
   no)
     if test -n "$with_cross_host" &&
        test x"$with_cross_host" != x"no"; then
       # Install a library built with a cross compiler in tooldir, not libdir.
       toolexecdir='$(exec_prefix)/$(target_alias)'
       case ${with_toolexeclibdir} in
 	no)
 	  toolexeclibdir='$(toolexecdir)/lib'
 	  ;;
 	*)
 	  toolexeclibdir=${with_toolexeclibdir}
 	  ;;
       esac
     else
       toolexecdir='$(libdir)/gcc-lib/$(target_alias)'
       toolexeclibdir='$(libdir)'
     fi
     multi_os_directory=`$CC -print-multi-os-directory`
     case $multi_os_directory in
       .) ;; # Avoid trailing /.
       *) toolexeclibdir=$toolexeclibdir/$multi_os_directory ;;
     esac
     ;;
 esac
 AC_SUBST(toolexecdir)
 AC_SUBST(toolexeclibdir)

 # Check the compiler.
 # The same as in boehm-gc and libstdc++. Have to borrow it from there.
 # We must force CC to /not/ be precious variables; otherwise
 # the wrong, non-multilib-adjusted value will be used in multilibs.
 # As a side effect, we have to subst CFLAGS ourselves.

 m4_rename([_AC_ARG_VAR_PRECIOUS],[real_PRECIOUS])
 m4_define([_AC_ARG_VAR_PRECIOUS],[])
 AC_PROG_CC
 m4_rename_force([real_PRECIOUS],[_AC_ARG_VAR_PRECIOUS])

 AC_SUBST(CFLAGS)

 # In order to override CFLAGS_FOR_TARGET, all of our special flags go
 # in XCFLAGS.  But we need them in CFLAGS during configury.  So put them
 # in both places for now and restore CFLAGS at the end of config.
 save_CFLAGS="$CFLAGS"

 AC_ARG_ENABLE([werror],
   [AS_HELP_STRING([--disable-werror], [disable building with -Werror])])
 # Add -Wall -Werror if we are using GCC.
 AS_IF([test "x$GCC" = "xyes"],
   [XCFLAGS="$XCFLAGS -Wall"])
 AS_IF([test "x$enable_werror" != "xno" && test "x$GCC" = "xyes"],
   [XCFLAGS="$XCFLAGS -Werror"])

 # Find other programs we need.
 AC_CHECK_TOOL(AR, ar)
 AC_CHECK_TOOL(RANLIB, ranlib, ranlib-not-found-in-path-error)
 AC_PATH_PROG(PERL, perl, perl-not-found-in-path-error)
 AC_PROG_MAKE_SET
 AC_PROG_INSTALL

 # See if makeinfo has been installed and is modern enough
 # that we can use it.
 ACX_CHECK_PROG_VER([MAKEINFO], [makeinfo], [--version],
                    [GNU texinfo.* \([0-9][0-9.]*\)],
                    [4.[4-9]*|4.[1-9][0-9]*|[5-9]*|[1-9][0-9]*])
 AM_CONDITIONAL(BUILD_INFO, test $gcc_cv_prog_makeinfo_modern = "yes")


 # Configure libtool
 AM_PROG_LIBTOOL
 ACX_LT_HOST_FLAGS
 AC_SUBST(enable_shared)
 AC_SUBST(enable_static)

 AM_MAINTAINER_MODE

 # Create a spec file, so that compile/link tests don't fail
 test -f libgfortran.spec || touch libgfortran.spec
 FCFLAGS="$FCFLAGS -L."

 # We need gfortran to compile parts of the library
 # We can't use AC_PROG_FC because it expects a fully working gfortran.
 #AC_PROG_FC(gfortran)
 case `echo $GFORTRAN` in
   -* | no* )
     FC=no ;;
   *)
     set dummy $GFORTRAN; ac_word=$2
     if test -x "$ac_word"; then
       FC="$GFORTRAN"
     else
       FC=no
     fi ;;
 esac
 AC_PROG_FC(gfortran)
 FCFLAGS="$FCFLAGS -Wall -L../libgfortran"

 # For libtool versioning info, format is CURRENT:REVISION:AGE
 libtool_VERSION=1:0:0
 AC_SUBST(libtool_VERSION)

 # Check header files.
 AC_STDC_HEADERS
 AC_HEADER_TIME
 ACX_HEADER_STRING
 AC_CHECK_HEADERS(pthread.h unistd.h semaphore.h sys/loadavg.h sys/sysctl.h sys/time.h)

 XPCFLAGS=""
 case "$host" in
   *-*-rtems*)
     # RTEMS supports Pthreads, but the library is not available at GCC build time.
     ;;
   nvptx*-*-* | amdgcn*-*-*)
     # NVPTX does not support Pthreads, has its own code replacement.
     libgomp_use_pthreads=no
     # NVPTX is an accelerator-only target
     libgomp_offloaded_only=yes
     ;;
   *)
     # Check to see if -pthread or -lpthread is needed.  Prefer the former.
     # In case the pthread.h system header is not found, this test will fail.
     CFLAGS="$CFLAGS -pthread"
     AC_LINK_IFELSE(
      [AC_LANG_PROGRAM(
       [#include <pthread.h>
        void *g(void *d) { return NULL; }],
       [pthread_t t; pthread_create(&t,NULL,g,NULL);])],
      [XPCFLAGS=" -Wc,-pthread"],
      [CFLAGS="$save_CFLAGS" LIBS="-lpthread $LIBS"
       AC_LINK_IFELSE(
        [AC_LANG_PROGRAM(
         [#include <pthread.h>
          void *g(void *d) { return NULL; }],
         [pthread_t t; pthread_create(&t,NULL,g,NULL);])],
        [],
        [AC_MSG_ERROR([Pthreads are required to build libgomp])])])
 esac

 if test x$libgomp_use_pthreads != xno; then
   AC_DEFINE(LIBGOMP_USE_PTHREADS, 1,
             [Define to 1 if libgomp should use POSIX threads.])
 fi

 if test x$libgomp_offloaded_only = xyes; then
   AC_DEFINE(LIBGOMP_OFFLOADED_ONLY, 1,
             [Define to 1 if building libgomp for an accelerator-only target.])
 fi

 if test "x$enable_offload_defaulted" = xyes; then
   AC_DEFINE(OFFLOAD_DEFAULTED, 1,
     [Define to 1 to if -foffload is defaulted])
 fi

 AC_CHECK_SIZEOF([void *])

 m4_include([plugin/configfrag.ac])

 # Check for functions needed.
 AC_CHECK_FUNCS(getloadavg clock_gettime strtoull)
 AC_CHECK_FUNCS(aligned_alloc posix_memalign memalign _aligned_malloc)

 # Check for broken semaphore implementation on darwin.
 # sem_init returns: sem_init error: Function not implemented.
 case "$host" in
   *-darwin*)
     AC_DEFINE(HAVE_BROKEN_POSIX_SEMAPHORES, 1,
 	Define if the POSIX Semaphores do not work on your system.)
     ;;
 esac

 # RTEMS specific checks
 case "$host" in
   *-*-rtems*)
     AC_CHECK_TYPES([struct _Mutex_Control],[],[],[#include <sys/lock.h>])
     ;;
 esac

 GCC_LINUX_FUTEX(:)

 # Check for pthread_{,attr_}[sg]etaffinity_np.
 AC_LINK_IFELSE(
  [AC_LANG_PROGRAM(
   [#define _GNU_SOURCE
    #include <pthread.h>],
   [cpu_set_t cpuset;
    pthread_attr_t attr;
    pthread_getaffinity_np (pthread_self (), sizeof (cpu_set_t), &cpuset);
    if (CPU_ISSET (0, &cpuset))
      CPU_SET (1, &cpuset);
    else
      CPU_ZERO (&cpuset);
    pthread_setaffinity_np (pthread_self (), sizeof (cpu_set_t), &cpuset);
    pthread_attr_init (&attr);
    pthread_attr_getaffinity_np (&attr, sizeof (cpu_set_t), &cpuset);
    pthread_attr_setaffinity_np (&attr, sizeof (cpu_set_t), &cpuset);])],
   AC_DEFINE(HAVE_PTHREAD_AFFINITY_NP, 1,
 [	Define if pthread_{,attr_}{g,s}etaffinity_np is supported.]))

 # At least for glibc, clock_gettime is in librt.  But don't pull that
 # in if it still doesn't give us the function we want.
 if test $ac_cv_func_clock_gettime = no; then
   AC_CHECK_LIB(rt, clock_gettime,
     [LIBS="-lrt $LIBS"
      AC_DEFINE(HAVE_CLOCK_GETTIME, 1,
 	       [Define to 1 if you have the `clock_gettime' function.])])
 fi

 # Check for uname.
 AC_COMPILE_IFELSE(
  [AC_LANG_PROGRAM(
   [#include <string.h>
    #include <stdlib.h>
    #include <sys/utsname.h>],
   [struct utsname buf;
    volatile size_t len = 0;
    if (!uname (buf))
      len = strlen (buf.nodename);])],
   AC_DEFINE(HAVE_UNAME, 1,
 [	Define if uname is supported and struct utsname has nodename field.]))

 # Check for gethostname.
 AC_COMPILE_IFELSE(
  [AC_LANG_PROGRAM(
   [#include <unistd.h>],
   [
 changequote(,)dnl
    char buf[256];
    if (gethostname (buf, sizeof (buf) - 1) == 0)
      buf[255] = '\0';
 changequote([,])dnl
   ])],
   AC_DEFINE(HAVE_GETHOSTNAME, 1,
 [	Define if gethostname is supported.]))

 # Check for getpid.
 AC_COMPILE_IFELSE(
  [AC_LANG_PROGRAM(
   [#include <unistd.h>],
   [int pid = getpid ();])],
   AC_DEFINE(HAVE_GETPID, 1,
 [	Define if getpid is supported.]))

 # See if we support thread-local storage.
 GCC_CHECK_TLS

 # See if we have emulated thread-local storage.
 GCC_CHECK_EMUTLS

 # See what sort of export controls are available.
 LIBGOMP_CHECK_ATTRIBUTE_VISIBILITY
 LIBGOMP_CHECK_ATTRIBUTE_DLLEXPORT
 LIBGOMP_CHECK_ATTRIBUTE_ALIAS
 LIBGOMP_ENABLE_SYMVERS

 if test $enable_symvers = gnu; then
   AC_DEFINE(LIBGOMP_GNU_SYMBOL_VERSIONING, 1,
 	    [Define to 1 if GNU symbol versioning is used for libgomp.])
 fi

 # Determine cpu count to limit testsuite parallelism.
 AX_COUNT_CPUS
 AC_SUBST(CPU_COUNT)

 # Get target configury.
 . ${srcdir}/configure.tgt
 CFLAGS="$save_CFLAGS $XCFLAGS"

 # Check for __sync_val_compare_and_swap, but only after the target has
 # had a chance to set XCFLAGS.
 LIBGOMP_CHECK_SYNC_BUILTINS

 XCFLAGS="$XCFLAGS$XPCFLAGS"

 # Add CET specific flags if CET is enabled
 GCC_CET_FLAGS(CET_FLAGS)
 XCFLAGS="$XCFLAGS $CET_FLAGS"
 FCFLAGS="$FCFLAGS $CET_FLAGS"

 AC_SUBST(config_path)
 AC_SUBST(XCFLAGS)
 AC_SUBST(XLDFLAGS)

 # Conditionalize the makefile for this target machine.
 tmake_file_=
 for f in ${tmake_file}
 do
 	if test -f ${srcdir}/config/$f
 	then
 		tmake_file_="${tmake_file_} \$(srcdir)/config/$f"
 	fi
 done
 tmake_file="${tmake_file_}"
 AC_SUBST(tmake_file)

 # Cleanup and exit.
 CFLAGS="$save_CFLAGS"
 AC_CACHE_SAVE

 if test ${multilib} = yes; then
   multilib_arg="--enable-multilib"
 else
   multilib_arg=
 fi

 # Set up the set of libraries that we need to link against for libgomp.
 # Note that the GOMP_SELF_SPEC in gcc.c may force -pthread,
 # which will force linkage against -lpthread (or equivalent for the system).
 # That's not 100% ideal, but about the best we can do easily.
 if test $enable_shared = yes; then
   link_gomp="-lgomp %{static: $LIBS}"
 else
   link_gomp="-lgomp $LIBS"
 fi
 AC_SUBST(link_gomp)

 AM_CONDITIONAL([USE_FORTRAN], [test "$ac_cv_fc_compiler_gnu" = yes])

 # ??? 2006-01-24: Paulo committed to asking autoconf folk to document
 # and export AC_COMPUTE_INT.  If that happens, then we'll need to remove
 # the underscore here and update the PREREQ.  If it doesn't, then we'll
 # need to copy this macro to our acinclude.m4.
 save_CFLAGS="$CFLAGS"
 for i in $config_path; do
   if test -f $srcdir/config/$i/omp-lock.h; then
     CFLAGS="$CFLAGS -include confdefs.h -include $srcdir/config/$i/omp-lock.h"
     break
   fi
 done

 _AC_COMPUTE_INT([sizeof (__INTPTR_TYPE__)], [INTPTR_T_KIND])
 _AC_COMPUTE_INT([sizeof (__int128)], [OMP_INT128_SIZE],,[OMP_INT128_SIZE=0])
 _AC_COMPUTE_INT([2*sizeof (__INTPTR_TYPE__)], [OMP_DEPEND_KIND],,
 		[OMP_DEPEND_KIND=0])
 _AC_COMPUTE_INT([sizeof (omp_lock_t)], [OMP_LOCK_SIZE],,
   [AC_MSG_ERROR([unsupported system, cannot find sizeof (omp_lock_t)])])
 _AC_COMPUTE_INT([__alignof (omp_lock_t)], [OMP_LOCK_ALIGN])
 _AC_COMPUTE_INT([sizeof (omp_nest_lock_t)], [OMP_NEST_LOCK_SIZE])
 _AC_COMPUTE_INT([__alignof (omp_nest_lock_t)], [OMP_NEST_LOCK_ALIGN])
 _AC_COMPUTE_INT([sizeof (omp_lock_25_t)], [OMP_LOCK_25_SIZE],,
   [AC_MSG_ERROR([unsupported system, cannot find sizeof (omp_lock_25_t)])])
 _AC_COMPUTE_INT([__alignof (omp_lock_25_t)], [OMP_LOCK_25_ALIGN])
 _AC_COMPUTE_INT([sizeof (omp_nest_lock_25_t)], [OMP_NEST_LOCK_25_SIZE])
 _AC_COMPUTE_INT([__alignof (omp_nest_lock_25_t)], [OMP_NEST_LOCK_25_ALIGN])

 # If the lock fits in an integer, then arrange for Fortran to use that
 # integer.  If it doesn't, then arrange for Fortran to use a pointer.
 # Except that we don't have a way at present to multi-lib the installed
 # Fortran modules, so we assume 8 bytes for pointers, regardless of the
 # actual target.
 OMP_LOCK_KIND=$OMP_LOCK_SIZE
 OMP_NEST_LOCK_KIND=$OMP_NEST_LOCK_SIZE
 if test $OMP_LOCK_SIZE -gt 8 || test $OMP_LOCK_ALIGN -gt $OMP_LOCK_SIZE; then
   OMP_LOCK_KIND=8
 fi
 if test $OMP_NEST_LOCK_SIZE -gt 8 || test $OMP_NEST_LOCK_ALIGN -gt $OMP_NEST_LOCK_SIZE; then
   OMP_NEST_LOCK_KIND=8
 fi
 OMP_LOCK_25_KIND=$OMP_LOCK_25_SIZE
 OMP_NEST_LOCK_25_KIND=$OMP_NEST_LOCK_25_SIZE
 if test $OMP_LOCK_25_SIZE -gt 8 || test $OMP_LOCK_25_ALIGN -gt $OMP_LOCK_25_SIZE; then
   OMP_LOCK_25_KIND=8
 fi
 if test $OMP_NEST_LOCK_25_SIZE -gt 8 || test $OMP_NEST_LOCK_25_ALIGN -gt $OMP_NEST_LOCK_25_SIZE; then
   OMP_NEST_LOCK_25_KIND=8
 fi
 if test "$ac_cv_fc_compiler_gnu" = yes; then
   if test $OMP_DEPEND_KIND -eq 16; then
     if test $OMP_INT128_SIZE -ne 16; then
       AC_MSG_ERROR([unsupported system, cannot find Fortran int kind=16, needed for omp_depend_kind])
     fi
   else
     if test $OMP_DEPEND_KIND -ne 8; then
       AC_MSG_ERROR([unsupported system, cannot find Fortran integer kind for omp_depend_kind])
     fi
   fi
 fi

 AC_SUBST(INTPTR_T_KIND)
 AC_SUBST(OMP_LOCK_SIZE)
 AC_SUBST(OMP_LOCK_ALIGN)
 AC_SUBST(OMP_NEST_LOCK_SIZE)
 AC_SUBST(OMP_NEST_LOCK_ALIGN)
 AC_SUBST(OMP_LOCK_KIND)
 AC_SUBST(OMP_NEST_LOCK_KIND)
 AC_SUBST(OMP_LOCK_25_SIZE)
 AC_SUBST(OMP_LOCK_25_ALIGN)
 AC_SUBST(OMP_NEST_LOCK_25_SIZE)
 AC_SUBST(OMP_NEST_LOCK_25_ALIGN)
 AC_SUBST(OMP_LOCK_25_KIND)
 AC_SUBST(OMP_NEST_LOCK_25_KIND)
 AC_SUBST(OMP_DEPEND_KIND)
 CFLAGS="$save_CFLAGS"

 # Determine what GCC version number to use in filesystem paths.
 GCC_BASE_VER

 AC_CONFIG_FILES(omp.h omp_lib.h omp_lib.f90 libgomp_f.h)
 AC_CONFIG_FILES(Makefile testsuite/Makefile libgomp.spec)
 AC_CONFIG_FILES([testsuite/libgomp-test-support.pt.exp:testsuite/libgomp-test-support.exp.in])
 AC_CONFIG_FILES([testsuite/libgomp-site-extra.exp])
 AC_OUTPUT
	# Process this file with autoconf to produce a configure script, like so:
	# aclocal -I ../config && autoconf && autoheader && automake

	AC_INIT([GNU Offloading and Multi Processing Runtime Library], 1.0,,[libgomp])
	AC_CONFIG_HEADER(config.h)

	# -------
	# Options
	# -------

	AC_MSG_CHECKING([for --enable-version-specific-runtime-libs])
	LIBGOMP_ENABLE(version-specific-runtime-libs, no, ,
	[Specify that runtime libraries should be installed in a compiler-specific directory],
	permit yes\|no)
	AC_MSG_RESULT($enable_version_specific_runtime_libs)

	# We would like our source tree to be readonly. However when releases or
	# pre-releases are generated, the flex/bison generated files as well as the
	# various formats of manuals need to be included along with the rest of the
	# sources. Therefore we have --enable-generated-files-in-srcdir to do
	# just that.
	AC_MSG_CHECKING([for --enable-generated-files-in-srcdir])
	LIBGOMP_ENABLE(generated-files-in-srcdir, no, ,
	[put copies of generated files in source dir intended for creating source
	tarballs for users without texinfo bison or flex.],
	permit yes\|no)
	AC_MSG_RESULT($enable_generated_files_in_srcdir)
	AM_CONDITIONAL(GENINSRC, test "$enable_generated_files_in_srcdir" = yes)


	# -------
	# -------

	# Gets build, host, target, _vendor, _cpu, *_os, etc.
	#
	# You will slowly go insane if you do not grok the following fact: when
	# building this library, the top-level /target/ becomes the library's /host/.
	#
	# configure then causes --target to default to --host, exactly like any
	# other package using autoconf. Therefore, 'target' and 'host' will
	# always be the same. This makes sense both for native and cross compilers
	# just think about it for a little while. :-)
	#
	# Also, if this library is being configured as part of a cross compiler, the
	# top-level configure script will pass the "real" host as $with_cross_host.
	#
	# Do not delete or change the following two lines. For why, see
	# http://gcc.gnu.org/ml/libstdc++/2003-07/msg00451.html
	AC_CANONICAL_SYSTEM
	target_alias=${target_alias-$host_alias}

	# Sets up automake. Must come after AC_CANONICAL_SYSTEM. Each of the
	# following is magically included in AUTOMAKE_OPTIONS in each Makefile.am.
	# 1.9.0: minimum required version
	# no-define: PACKAGE and VERSION will not be #define'd in config.h (a bunch
	# of other PACKAGE_* variables will, however, and there's nothing
	# we can do about that; they come from AC_INIT).
	# foreign: we don't follow the normal rules for GNU packages (no COPYING
	# file in the top srcdir, etc, etc), so stop complaining.
	# no-dist: we don't want 'dist' and related rules.
	# -Wall: turns on all automake warnings...
	# -Wno-portability: ...except this one, since GNU make is required.
	# -Wno-override: ... and this one, since we do want this in testsuite.
	AM_INIT_AUTOMAKE([1.9.0 foreign no-dist -Wall -Wno-portability -Wno-override])
	AM_ENABLE_MULTILIB(, ..)

	GCC_WITH_TOOLEXECLIBDIR

	# Calculate toolexeclibdir
	# Also toolexecdir, though it's only used in toolexeclibdir
	case ${enable_version_specific_runtime_libs} in
	yes)
	# Need the gcc compiler version to know where to install libraries
	# and header files if --enable-version-specific-runtime-libs option
	# is selected.
	toolexecdir='$(libdir)/gcc/$(target_alias)'
	toolexeclibdir='$(toolexecdir)/$(gcc_version)$(MULTISUBDIR)'
	;;
	no)
	if test -n "$with_cross_host" &&
	test x"$with_cross_host" != x"no"; then
	# Install a library built with a cross compiler in tooldir, not libdir.
	toolexecdir='$(exec_prefix)/$(target_alias)'
	case ${with_toolexeclibdir} in
	no)
	toolexeclibdir='$(toolexecdir)/lib'
	;;
	*)
	toolexeclibdir=${with_toolexeclibdir}
	;;
	esac
	else
	toolexecdir='$(libdir)/gcc-lib/$(target_alias)'
	toolexeclibdir='$(libdir)'
	fi
	multi_os_directory=`$CC -print-multi-os-directory`
	case $multi_os_directory in
	.) ;; # Avoid trailing /.
	*) toolexeclibdir=$toolexeclibdir/$multi_os_directory ;;
	esac
	;;
	esac
	AC_SUBST(toolexecdir)
	AC_SUBST(toolexeclibdir)

	# Check the compiler.
	# The same as in boehm-gc and libstdc++. Have to borrow it from there.
	# We must force CC to /not/ be precious variables; otherwise
	# the wrong, non-multilib-adjusted value will be used in multilibs.
	# As a side effect, we have to subst CFLAGS ourselves.

	m4_rename([_AC_ARG_VAR_PRECIOUS],[real_PRECIOUS])
	m4_define([_AC_ARG_VAR_PRECIOUS],[])
	AC_PROG_CC
	m4_rename_force([real_PRECIOUS],[_AC_ARG_VAR_PRECIOUS])

	AC_SUBST(CFLAGS)

	# In order to override CFLAGS_FOR_TARGET, all of our special flags go
	# in XCFLAGS. But we need them in CFLAGS during configury. So put them
	# in both places for now and restore CFLAGS at the end of config.
	save_CFLAGS="$CFLAGS"

	AC_ARG_ENABLE([werror],
	[AS_HELP_STRING([--disable-werror], [disable building with -Werror])])
	# Add -Wall -Werror if we are using GCC.
	AS_IF([test "x$GCC" = "xyes"],
	[XCFLAGS="$XCFLAGS -Wall"])
	AS_IF([test "x$enable_werror" != "xno" && test "x$GCC" = "xyes"],
	[XCFLAGS="$XCFLAGS -Werror"])

	# Find other programs we need.
	AC_CHECK_TOOL(AR, ar)
	AC_CHECK_TOOL(RANLIB, ranlib, ranlib-not-found-in-path-error)
	AC_PATH_PROG(PERL, perl, perl-not-found-in-path-error)
	AC_PROG_MAKE_SET
	AC_PROG_INSTALL

	# See if makeinfo has been installed and is modern enough
	# that we can use it.
	ACX_CHECK_PROG_VER([MAKEINFO], [makeinfo], [--version],
	[GNU texinfo.* \([0-9][0-9.]*\)],
	[4.[4-9]\|4.[1-9][0-9]\|[5-9]\|[1-9][0-9]])
	AM_CONDITIONAL(BUILD_INFO, test $gcc_cv_prog_makeinfo_modern = "yes")


	# Configure libtool
	AM_PROG_LIBTOOL
	ACX_LT_HOST_FLAGS
	AC_SUBST(enable_shared)
	AC_SUBST(enable_static)

	AM_MAINTAINER_MODE

	# Create a spec file, so that compile/link tests don't fail
	test -f libgfortran.spec \|\| touch libgfortran.spec
	FCFLAGS="$FCFLAGS -L."

	# We need gfortran to compile parts of the library
	# We can't use AC_PROG_FC because it expects a fully working gfortran.
	#AC_PROG_FC(gfortran)
	case `echo $GFORTRAN` in
	-* \| no* )
	FC=no ;;
	*)
	set dummy $GFORTRAN; ac_word=$2
	if test -x "$ac_word"; then
	FC="$GFORTRAN"
	else
	FC=no
	fi ;;
	esac
	AC_PROG_FC(gfortran)
	FCFLAGS="$FCFLAGS -Wall -L../libgfortran"

	# For libtool versioning info, format is CURRENT:REVISION:AGE
	libtool_VERSION=1:0:0
	AC_SUBST(libtool_VERSION)

	# Check header files.
	AC_STDC_HEADERS
	AC_HEADER_TIME
	ACX_HEADER_STRING
	AC_CHECK_HEADERS(pthread.h unistd.h semaphore.h sys/loadavg.h sys/sysctl.h sys/time.h)

	XPCFLAGS=""
	case "$host" in
	--rtems*)
	# RTEMS supports Pthreads, but the library is not available at GCC build time.
	;;
	nvptx--* \| amdgcn--*)
	# NVPTX does not support Pthreads, has its own code replacement.
	libgomp_use_pthreads=no
	# NVPTX is an accelerator-only target
	libgomp_offloaded_only=yes
	;;
	*)
	# Check to see if -pthread or -lpthread is needed. Prefer the former.
	# In case the pthread.h system header is not found, this test will fail.
	CFLAGS="$CFLAGS -pthread"
	AC_LINK_IFELSE(
	[AC_LANG_PROGRAM(
	[#include <pthread.h>
	void g(void d) { return NULL; }],
	[pthread_t t; pthread_create(&t,NULL,g,NULL);])],
	[XPCFLAGS=" -Wc,-pthread"],
	[CFLAGS="$save_CFLAGS" LIBS="-lpthread $LIBS"
	AC_LINK_IFELSE(
	[AC_LANG_PROGRAM(
	[#include <pthread.h>
	void g(void d) { return NULL; }],
	[pthread_t t; pthread_create(&t,NULL,g,NULL);])],
	[],
	[AC_MSG_ERROR([Pthreads are required to build libgomp])])])
	esac

	if test x$libgomp_use_pthreads != xno; then
	AC_DEFINE(LIBGOMP_USE_PTHREADS, 1,
	[Define to 1 if libgomp should use POSIX threads.])
	fi

	if test x$libgomp_offloaded_only = xyes; then
	AC_DEFINE(LIBGOMP_OFFLOADED_ONLY, 1,
	[Define to 1 if building libgomp for an accelerator-only target.])
	fi

	if test "x$enable_offload_defaulted" = xyes; then
	AC_DEFINE(OFFLOAD_DEFAULTED, 1,
	[Define to 1 to if -foffload is defaulted])
	fi

	AC_CHECK_SIZEOF([void *])

	m4_include([plugin/configfrag.ac])

	# Check for functions needed.
	AC_CHECK_FUNCS(getloadavg clock_gettime strtoull)
	AC_CHECK_FUNCS(aligned_alloc posix_memalign memalign _aligned_malloc)

	# Check for broken semaphore implementation on darwin.
	# sem_init returns: sem_init error: Function not implemented.
	case "$host" in
	-darwin)
	AC_DEFINE(HAVE_BROKEN_POSIX_SEMAPHORES, 1,
	Define if the POSIX Semaphores do not work on your system.)
	;;
	esac

	# RTEMS specific checks
	case "$host" in
	--rtems*)
	AC_CHECK_TYPES([struct _Mutex_Control],[],[],[#include <sys/lock.h>])
	;;
	esac

	GCC_LINUX_FUTEX(:)

	# Check for pthread_{,attr_}[sg]etaffinity_np.
	AC_LINK_IFELSE(
	[AC_LANG_PROGRAM(
	[#define _GNU_SOURCE
	#include <pthread.h>],
	[cpu_set_t cpuset;
	pthread_attr_t attr;
	pthread_getaffinity_np (pthread_self (), sizeof (cpu_set_t), &cpuset);
	if (CPU_ISSET (0, &cpuset))
	CPU_SET (1, &cpuset);
	else
	CPU_ZERO (&cpuset);
	pthread_setaffinity_np (pthread_self (), sizeof (cpu_set_t), &cpuset);
	pthread_attr_init (&attr);
	pthread_attr_getaffinity_np (&attr, sizeof (cpu_set_t), &cpuset);
	pthread_attr_setaffinity_np (&attr, sizeof (cpu_set_t), &cpuset);])],
	AC_DEFINE(HAVE_PTHREAD_AFFINITY_NP, 1,
	[ Define if pthread_{,attr_}{g,s}etaffinity_np is supported.]))

	# At least for glibc, clock_gettime is in librt. But don't pull that
	# in if it still doesn't give us the function we want.
	if test $ac_cv_func_clock_gettime = no; then
	AC_CHECK_LIB(rt, clock_gettime,
	[LIBS="-lrt $LIBS"
	AC_DEFINE(HAVE_CLOCK_GETTIME, 1,
	[Define to 1 if you have the `clock_gettime' function.])])
	fi

	# Check for uname.
	AC_COMPILE_IFELSE(
	[AC_LANG_PROGRAM(
	[#include <string.h>
	#include <stdlib.h>
	#include <sys/utsname.h>],
	[struct utsname buf;
	volatile size_t len = 0;
	if (!uname (buf))
	len = strlen (buf.nodename);])],
	AC_DEFINE(HAVE_UNAME, 1,
	[ Define if uname is supported and struct utsname has nodename field.]))

	# Check for gethostname.
	AC_COMPILE_IFELSE(
	[AC_LANG_PROGRAM(
	[#include <unistd.h>],
	[
	changequote(,)dnl
	char buf[256];
	if (gethostname (buf, sizeof (buf) - 1) == 0)
	buf[255] = '\0';
	changequote([,])dnl
	])],
	AC_DEFINE(HAVE_GETHOSTNAME, 1,
	[ Define if gethostname is supported.]))

	# Check for getpid.
	AC_COMPILE_IFELSE(
	[AC_LANG_PROGRAM(
	[#include <unistd.h>],
	[int pid = getpid ();])],
	AC_DEFINE(HAVE_GETPID, 1,
	[ Define if getpid is supported.]))

	# See if we support thread-local storage.
	GCC_CHECK_TLS

	# See if we have emulated thread-local storage.
	GCC_CHECK_EMUTLS

	# See what sort of export controls are available.
	LIBGOMP_CHECK_ATTRIBUTE_VISIBILITY
	LIBGOMP_CHECK_ATTRIBUTE_DLLEXPORT
	LIBGOMP_CHECK_ATTRIBUTE_ALIAS
	LIBGOMP_ENABLE_SYMVERS

	if test $enable_symvers = gnu; then
	AC_DEFINE(LIBGOMP_GNU_SYMBOL_VERSIONING, 1,
	[Define to 1 if GNU symbol versioning is used for libgomp.])
	fi

	# Determine cpu count to limit testsuite parallelism.
	AX_COUNT_CPUS
	AC_SUBST(CPU_COUNT)

	# Get target configury.
	. ${srcdir}/configure.tgt
	CFLAGS="$save_CFLAGS $XCFLAGS"

	# Check for __sync_val_compare_and_swap, but only after the target has
	# had a chance to set XCFLAGS.
	LIBGOMP_CHECK_SYNC_BUILTINS

	XCFLAGS="$XCFLAGS$XPCFLAGS"

	# Add CET specific flags if CET is enabled
	GCC_CET_FLAGS(CET_FLAGS)
	XCFLAGS="$XCFLAGS $CET_FLAGS"
	FCFLAGS="$FCFLAGS $CET_FLAGS"

	AC_SUBST(config_path)
	AC_SUBST(XCFLAGS)
	AC_SUBST(XLDFLAGS)

	# Conditionalize the makefile for this target machine.
	tmake_file_=
	for f in ${tmake_file}
	do
	if test -f ${srcdir}/config/$f
	then
	tmake_file_="${tmake_file_} \$(srcdir)/config/$f"
	fi
	done
	tmake_file="${tmake_file_}"
	AC_SUBST(tmake_file)

	# Cleanup and exit.
	CFLAGS="$save_CFLAGS"
	AC_CACHE_SAVE

	if test ${multilib} = yes; then
	multilib_arg="--enable-multilib"
	else
	multilib_arg=
	fi

	# Set up the set of libraries that we need to link against for libgomp.
	# Note that the GOMP_SELF_SPEC in gcc.c may force -pthread,
	# which will force linkage against -lpthread (or equivalent for the system).
	# That's not 100% ideal, but about the best we can do easily.
	if test $enable_shared = yes; then
	link_gomp="-lgomp %{static: $LIBS}"
	else
	link_gomp="-lgomp $LIBS"
	fi
	AC_SUBST(link_gomp)

	AM_CONDITIONAL([USE_FORTRAN], [test "$ac_cv_fc_compiler_gnu" = yes])

	# ??? 2006-01-24: Paulo committed to asking autoconf folk to document
	# and export AC_COMPUTE_INT. If that happens, then we'll need to remove
	# the underscore here and update the PREREQ. If it doesn't, then we'll
	# need to copy this macro to our acinclude.m4.
	save_CFLAGS="$CFLAGS"
	for i in $config_path; do
	if test -f $srcdir/config/$i/omp-lock.h; then
	CFLAGS="$CFLAGS -include confdefs.h -include $srcdir/config/$i/omp-lock.h"
	break
	fi
	done

	_AC_COMPUTE_INT([sizeof (__INTPTR_TYPE__)], [INTPTR_T_KIND])
	_AC_COMPUTE_INT([sizeof (__int128)], [OMP_INT128_SIZE],,[OMP_INT128_SIZE=0])
	_AC_COMPUTE_INT([2*sizeof (__INTPTR_TYPE__)], [OMP_DEPEND_KIND],,
	[OMP_DEPEND_KIND=0])
	_AC_COMPUTE_INT([sizeof (omp_lock_t)], [OMP_LOCK_SIZE],,
	[AC_MSG_ERROR([unsupported system, cannot find sizeof (omp_lock_t)])])
	_AC_COMPUTE_INT([__alignof (omp_lock_t)], [OMP_LOCK_ALIGN])
	_AC_COMPUTE_INT([sizeof (omp_nest_lock_t)], [OMP_NEST_LOCK_SIZE])
	_AC_COMPUTE_INT([__alignof (omp_nest_lock_t)], [OMP_NEST_LOCK_ALIGN])
	_AC_COMPUTE_INT([sizeof (omp_lock_25_t)], [OMP_LOCK_25_SIZE],,
	[AC_MSG_ERROR([unsupported system, cannot find sizeof (omp_lock_25_t)])])
	_AC_COMPUTE_INT([__alignof (omp_lock_25_t)], [OMP_LOCK_25_ALIGN])
	_AC_COMPUTE_INT([sizeof (omp_nest_lock_25_t)], [OMP_NEST_LOCK_25_SIZE])
	_AC_COMPUTE_INT([__alignof (omp_nest_lock_25_t)], [OMP_NEST_LOCK_25_ALIGN])

	# If the lock fits in an integer, then arrange for Fortran to use that
	# integer. If it doesn't, then arrange for Fortran to use a pointer.
	# Except that we don't have a way at present to multi-lib the installed
	# Fortran modules, so we assume 8 bytes for pointers, regardless of the
	# actual target.
	OMP_LOCK_KIND=$OMP_LOCK_SIZE
	OMP_NEST_LOCK_KIND=$OMP_NEST_LOCK_SIZE
	if test $OMP_LOCK_SIZE -gt 8 \|\| test $OMP_LOCK_ALIGN -gt $OMP_LOCK_SIZE; then
	OMP_LOCK_KIND=8
	fi
	if test $OMP_NEST_LOCK_SIZE -gt 8 \|\| test $OMP_NEST_LOCK_ALIGN -gt $OMP_NEST_LOCK_SIZE; then
	OMP_NEST_LOCK_KIND=8
	fi
	OMP_LOCK_25_KIND=$OMP_LOCK_25_SIZE
	OMP_NEST_LOCK_25_KIND=$OMP_NEST_LOCK_25_SIZE
	if test $OMP_LOCK_25_SIZE -gt 8 \|\| test $OMP_LOCK_25_ALIGN -gt $OMP_LOCK_25_SIZE; then
	OMP_LOCK_25_KIND=8
	fi
	if test $OMP_NEST_LOCK_25_SIZE -gt 8 \|\| test $OMP_NEST_LOCK_25_ALIGN -gt $OMP_NEST_LOCK_25_SIZE; then
	OMP_NEST_LOCK_25_KIND=8
	fi
	if test "$ac_cv_fc_compiler_gnu" = yes; then
	if test $OMP_DEPEND_KIND -eq 16; then
	if test $OMP_INT128_SIZE -ne 16; then
	AC_MSG_ERROR([unsupported system, cannot find Fortran int kind=16, needed for omp_depend_kind])
	fi
	else
	if test $OMP_DEPEND_KIND -ne 8; then
	AC_MSG_ERROR([unsupported system, cannot find Fortran integer kind for omp_depend_kind])
	fi
	fi
	fi

	AC_SUBST(INTPTR_T_KIND)
	AC_SUBST(OMP_LOCK_SIZE)
	AC_SUBST(OMP_LOCK_ALIGN)
	AC_SUBST(OMP_NEST_LOCK_SIZE)
	AC_SUBST(OMP_NEST_LOCK_ALIGN)
	AC_SUBST(OMP_LOCK_KIND)
	AC_SUBST(OMP_NEST_LOCK_KIND)
	AC_SUBST(OMP_LOCK_25_SIZE)
	AC_SUBST(OMP_LOCK_25_ALIGN)
	AC_SUBST(OMP_NEST_LOCK_25_SIZE)
	AC_SUBST(OMP_NEST_LOCK_25_ALIGN)
	AC_SUBST(OMP_LOCK_25_KIND)
	AC_SUBST(OMP_NEST_LOCK_25_KIND)
	AC_SUBST(OMP_DEPEND_KIND)
	CFLAGS="$save_CFLAGS"

	# Determine what GCC version number to use in filesystem paths.
	GCC_BASE_VER

	AC_CONFIG_FILES(omp.h omp_lib.h omp_lib.f90 libgomp_f.h)
	AC_CONFIG_FILES(Makefile testsuite/Makefile libgomp.spec)
	AC_CONFIG_FILES([testsuite/libgomp-test-support.pt.exp:testsuite/libgomp-test-support.exp.in])
	AC_CONFIG_FILES([testsuite/libgomp-site-extra.exp])
	AC_OUTPUT