This goes with the patch for #1839, #1463
[ghc-hetmet.git] / aclocal.m4
index 40c1f26..d30b101 100644 (file)
-dnl $Id: aclocal.m4,v 1.47 2000/05/09 10:43:45 rrt Exp $
-dnl 
-dnl Extra autoconf macros for the Glasgow fptools
-dnl
-dnl To be a good autoconf citizen, names of local macros have
-dnl prefixed with FPTOOLS_ to ensure we don't clash
-dnl with any pre-supplied autoconf ones.
+# Extra autoconf macros for the Glasgow fptools
+#
+# To be a good autoconf citizen, names of local macros have prefixed with FP_ to
+# ensure we don't clash with any pre-supplied autoconf ones.
 
-dnl
-dnl Is timezone around? (in a header file)
-dnl 
-AC_DEFUN(FPTOOLS_HAVE_TIMEZONE,
-[AC_CACHE_CHECK([timezone], fptools_cv_have_timezone,
-[AC_TRY_COMPILE([#if TIME_WITH_SYS_TIME
-# include <sys/time.h>
-# include <time.h>
-#else
-# if HAVE_SYS_TIME_H
-#  include <sys/time.h>
-# else
-#  include <time.h>
-# endif
-#endif
-], [return timezone;], 
-fptools_cv_have_timezone=yes, fptools_cv_have_timezone=no)])
-if test "$fptools_cv_have_timezone" = yes; then
-  AC_DEFINE(HAVE_TIMEZONE)
-fi
+
+# FPTOOLS_FLOAT_WORD_ORDER_BIGENDIAN
+# ----------------------------------
+# Little endian Arm on Linux with some ABIs has big endian word order
+# in doubles. Define FLOAT_WORDS_BIGENDIAN if this is the case.
+AC_DEFUN([FPTOOLS_FLOAT_WORD_ORDER_BIGENDIAN],
+  [AC_CACHE_CHECK([whether float word order is big endian], [fptools_cv_float_word_order_bigendian],
+    [AC_COMPILE_IFELSE(
+      [AC_LANG_PROGRAM(
+        [#include <endian.h>],
+        [#if defined(__FLOAT_WORD_ORDER) && __FLOAT_WORD_ORDER == BIG_ENDIAN
+             return 0;
+         #else
+             not float word order big endian
+         #endif]
+      )],
+      [fptools_cv_float_word_order_bigendian=yes],
+      [fptools_cv_float_word_order_bigendian=no])
+    ])
+  case $fptools_cv_float_word_order_bigendian in
+      yes)
+          AC_DEFINE([FLOAT_WORDS_BIGENDIAN], 1,
+          [Define to 1 if your processor stores words of floats with
+           the most significant byte first]) ;;
+  esac
 ])
 
-dnl
-dnl Has timezone the type time_t or long (HP-UX 10.20 apparently
-dnl has `long'..)
-dnl 
-AC_DEFUN(FPTOOLS_TYPE_TIMEZONE,
-[AC_CACHE_CHECK([type of timezone], fptools_cv_type_timezone,
-[AC_TRY_COMPILE([#if TIME_WITH_SYS_TIME
-# include <sys/time.h>
-# include <time.h>
-#else
-# if HAVE_SYS_TIME_H
-#  include <sys/time.h>
-# else
-#  include <time.h>
-# endif
-#endif
 
-extern time_t timezone;        
-],
-[int i;], fptools_cv_type_timezone=time_t, fptools_cv_type_timezone=long)])
-AC_DEFINE_UNQUOTED(TYPE_TIMEZONE, $fptools_cv_type_timezone)
-])
+# FP_EVAL_STDERR(COMMAND)
+# -----------------------
+# Eval COMMAND, save its stderr (without lines resulting from shell tracing)
+# into the file conftest.err and the exit status in the variable fp_status.
+AC_DEFUN([FP_EVAL_STDERR],
+[{ (eval $1) 2>conftest.er1
+  fp_status=$?
+  grep -v '^ *+' conftest.er1 >conftest.err
+  rm -f conftest.er1
+  (exit $fp_status); }[]dnl
+])# FP_EVAL_STDERR
 
-dnl *** Is altzone available? ***
-dnl 
-AC_DEFUN(FPTOOLS_ALTZONE,
-[AC_CACHE_CHECK([altzone], fptools_cv_altzone,
-[AC_TRY_LINK([#if TIME_WITH_SYS_TIME
-# include <sys/time.h>
-# include <time.h>
-#else
-# if HAVE_SYS_TIME_H
-#  include <sys/time.h>
-# else
-#  include <time.h>
-# endif
-#endif
-], [return altzone;], 
-fptools_cv_altzone=yes, fptools_cv_altzone=no)])
-if test "$fptools_cv_altzone" = yes; then
-  AC_DEFINE(HAVE_ALTZONE)
+
+# FP_CHECK_FLAG(FLAG, [ACTION-IF-SUPPORTED], [ACTION-IF-NOT-SUPPORTED])
+# ---------------------------------------------------------------------
+# Check to see whether the compiler for the current language supports a
+# particular option.
+#
+# Implementation note: When given an unkown option, GCC issues an warning on
+# stderr only, but returns an exit value of 0 nevertheless. Consequently we have
+# to check stderr *and* the exit value.
+#
+# Used by ghc.
+AC_DEFUN([FP_CHECK_FLAG],
+[AC_LANG_COMPILER_REQUIRE()dnl
+AC_LANG_CASE([C],          [fp_compiler="$CC"  m4_pushdef([fp_Flags], [CFLAGS])],
+             [C++],        [fp_compiler="$CXX" m4_pushdef([fp_Flags], [CXXFLAGS])],
+             [Fortran 77], [fp_compiler="$F77" m4_pushdef([fp_Flags], [FFLAGS])])
+m4_pushdef([fp_Cache], [fp_cv_[]fp_Flags[]AS_TR_SH([$1])])[]dnl
+AC_CACHE_CHECK([whether $fp_compiler accepts $1], [fp_Cache],
+[AC_LANG_CONFTEST([AC_LANG_PROGRAM()])
+fp_save_flags="$fp_Flags"
+fp_Flags="$fp_Flags $1"
+fp_Cache=no
+if FP_EVAL_STDERR([$ac_compile conftest.$ac_ext]) >/dev/null; then
+  test -s conftest.err || fp_Cache=yes
 fi
-])
+fp_Flags="$fp_save_flags"
+rm -f conftest.err conftest.$ac_ext])
+AS_IF([test $fp_Cache = yes], [$2], [$3])[]dnl
+m4_popdef([fp_Cache])[]dnl
+m4_popdef([fp_Flags])[]dnl
+])# FP_CHECK_FLAG
 
 
-dnl ** check for leading underscores in symbol names
-dnl 
-dnl Test for determining whether symbol names have a leading
-dnl underscore.
-dnl 
-dnl We assume that they _haven't_ if anything goes wrong.
-dnl
-dnl Some nlist implementations seem to try to be compatible by ignoring
-dnl a leading underscore sometimes (eg. FreeBSD).  We therefore have
-dnl to work around this by checking for *no* leading underscore first.
-dnl Sigh.  --SDM
-dnl
-AC_DEFUN(FPTOOLS_UNDERSCORE,
-[AC_CHECK_LIB(elf, nlist, LIBS="-lelf $LIBS")dnl
-AC_CACHE_CHECK([leading underscore in symbol names], fptools_cv_lead_uscore,
+# FP_PROG_CONTEXT_DIFF
+# --------------------
+# Figure out how to do context diffs. Sets the output variable ContextDiffCmd.
+#
+# Note: NeXTStep thinks diff'ing a file against itself is "trouble".
+#
+# Used by ghc, glafp-utils/ltx, and glafp-utils/runstdtest.
+AC_DEFUN([FP_PROG_CONTEXT_DIFF],
+[AC_CACHE_CHECK([for a working context diff], [fp_cv_context_diff],
+[echo foo > conftest1
+echo foo > conftest2
+fp_cv_context_diff=no
+for fp_var in '-C 1' '-c1'
+do
+  if diff $fp_var conftest1 conftest2 > /dev/null 2>&1; then
+    fp_cv_context_diff="diff $fp_var"
+    break
+  fi
+done])
+if test x"$fp_cv_context_diff" = xno; then
+   AC_MSG_ERROR([cannot figure out how to do context diffs])
+fi
+AC_SUBST(ContextDiffCmd, [$fp_cv_context_diff])
+])# FP_PROG_CONTEXT_DIFF
 
-dnl
-dnl Hack!: nlist() under Digital UNIX insist on there being an _,
-dnl but symbol table listings shows none. What is going on here?!?
-dnl
-dnl Another hack: cygwin doesn't come with nlist.h , so we hardwire
-dnl the underscoredness of that "platform"
-changequote(<<, >>)dnl
-<<
+
+# FP_COMPUTE_INT(EXPRESSION, VARIABLE, INCLUDES, IF-FAILS)
+# --------------------------------------------------------
+# Assign VARIABLE the value of the compile-time EXPRESSION using INCLUDES for
+# compilation. Execute IF-FAILS when unable to determine the value. Works for
+# cross-compilation, too.
+#
+# Implementation note: We are lazy and use an internal autoconf macro, but it
+# is supported in autoconf versions 2.50 up to the actual 2.57, so there is
+# little risk.
+AC_DEFUN([FP_COMPUTE_INT],
+[_AC_COMPUTE_INT([$1], [$2], [$3], [$4])[]dnl
+])# FP_COMPUTE_INT
+
+
+# FP_CHECK_ALIGNMENT(TYPE, [IGNORED], [INCLUDES = DEFAULT-INCLUDES])
+# ------------------------------------------------------------------
+# A variation of AC_CHECK_SIZEOF for computing the alignment restrictions of a
+# given type. Defines ALIGNMENT_TYPE.
+AC_DEFUN([FP_CHECK_ALIGNMENT],
+[AS_LITERAL_IF([$1], [],
+               [AC_FATAL([$0: requires literal arguments])])[]dnl
+AC_CHECK_TYPE([$1], [], [], [$3])[]dnl
+m4_pushdef([fp_Cache], [AS_TR_SH([fp_cv_alignment_$1])])[]dnl
+AC_CACHE_CHECK([alignment of $1], [fp_Cache],
+[if test "$AS_TR_SH([ac_cv_type_$1])" = yes; then
+  FP_COMPUTE_INT([(long) (&((struct { char c; $1 ty; } *)0)->ty)],
+                 [fp_Cache],
+                 [AC_INCLUDES_DEFAULT([$3])],
+                 [AC_MSG_ERROR([cannot compute alignment ($1)
+See `config.log' for more details.], [77])])
+else
+  fp_Cache=0
+fi])[]dnl
+AC_DEFINE_UNQUOTED(AS_TR_CPP(alignment_$1), $fp_Cache, [The alignment of a `$1'.])[]dnl
+m4_popdef([fp_Cache])[]dnl
+])# FP_CHECK_ALIGNMENT
+
+
+# FP_LEADING_UNDERSCORE
+# ---------------------
+# Test for determining whether symbol names have a leading underscore. We assume
+# that they _haven't_ if anything goes wrong. Sets the output variable
+# LeadingUnderscore to YES or NO and defines LEADING_UNDERSCORE correspondingly.
+#
+# Some nlist implementations seem to try to be compatible by ignoring a leading
+# underscore sometimes (eg. FreeBSD). We therefore have to work around this by
+# checking for *no* leading underscore first. Sigh.  --SDM
+#
+# Similarly on OpenBSD, but this test doesn't help. -- dons
+AC_DEFUN([FP_LEADING_UNDERSCORE],
+[AC_CHECK_LIB([elf], [nlist], [LIBS="-lelf $LIBS"])
+AC_CACHE_CHECK([leading underscore in symbol names], [fptools_cv_leading_underscore], [
+# Hack!: nlist() under Digital UNIX insist on there being an _,
+# but symbol table listings shows none. What is going on here?!?
+#
+# Another hack: cygwin doesn't come with nlist.h , so we hardwire
+# the underscoredness of that "platform"
 case $HostPlatform in
-alpha-dec-osf*) fptools_cv_lead_uscore='no';;
-*cygwin32) fptools_cv_lead_uscore='yes';;
-*mingw32) fptools_cv_lead_uscore='yes';;
-*) >>
-changequote([, ])dnl
-AC_TRY_RUN([#ifdef HAVE_NLIST_H
+*openbsd*) # x86 openbsd is ELF from 3.4 >, meaning no leading uscore
+  case $build in
+    i386-*2\.@<:@0-9@:>@ | i386-*3\.@<:@0-3@:>@ ) fptools_cv_leading_underscore=yes ;;
+    *) fptools_cv_leading_underscore=no ;;
+  esac ;;
+alpha-dec-osf*) fptools_cv_leading_underscore=no;;
+*cygwin32) fptools_cv_leading_underscore=yes;;
+*mingw32) fptools_cv_leading_underscore=yes;;
+
+    # HACK: Apple doesn't seem to provide nlist in the 64-bit-libraries
+x86_64-apple-darwin*) fptools_cv_leading_underscore=yes;;
+
+*) AC_RUN_IFELSE([AC_LANG_SOURCE([[#ifdef HAVE_NLIST_H
 #include <nlist.h>
-changequote(<<, >>)dnl
-<<
 struct nlist xYzzY1[] = {{"xYzzY1", 0},{0}};
 struct nlist xYzzY2[] = {{"_xYzzY2", 0},{0}};
 #endif
 
-main(argc, argv)
+int main(argc, argv)
 int argc;
 char **argv;
 {
@@ -119,160 +186,334 @@ char **argv;
     if(nlist(argv[0], xYzzY1) == 0 && xYzzY1[0].n_value != 0)
         exit(1);
     if(nlist(argv[0], xYzzY2) == 0 && xYzzY2[0].n_value != 0)
-        exit(0);>>
-changequote([, ])dnl
+        exit(0);
 #endif
     exit(1);
-}], fptools_cv_lead_uscore=yes, fptools_cv_lead_uscore=no, fptools_cv_lead_uscore=NO)
+}]])],[fptools_cv_leading_underscore=yes],[fptools_cv_leading_underscore=no],[fptools_cv_leading_underscore=no])
 ;;
-esac);
-LeadingUnderscore=`echo $fptools_cv_lead_uscore | sed 'y/yesno/YESNO/'`
-AC_SUBST(LeadingUnderscore)
-case $LeadingUnderscore in
-YES) AC_DEFINE(LEADING_UNDERSCORE);;
-esac
+esac]);
+AC_SUBST([LeadingUnderscore], [`echo $fptools_cv_leading_underscore | sed 'y/yesno/YESNO/'`])
+if test x"$fptools_cv_leading_underscore" = xyes; then
+   AC_DEFINE([LEADING_UNDERSCORE], [1], [Define to 1 if C symbols have a leading underscore added by the compiler.])
+fi])# FP_LEADING_UNDERSCORE
+
+
+# FP_COMPARE_VERSIONS(VERSION1, TEST, VERSION2, [ACTION-IF-TRUE], [ACTION-IF-FALSE])
+# ----------------------------------------------------------------------------------
+# Compare dotted version numbers VERSION1 and VERSION2 lexicographically according
+# to TEST (one of -eq, -ne, -lt, -le, -gt, or -ge).
+AC_DEFUN([FP_COMPARE_VERSIONS],
+[fp_version1=$1; fp_version2=$3
+fp_save_IFS=$IFS; IFS='.'
+while test x"$fp_version1" != x || test x"$fp_version2" != x
+do
+
+  set dummy $fp_version1; shift
+  fp_num1=""
+  test $[@%:@] = 0 || { fp_num1="[$]1"; shift; }
+  test x"$fp_num1" = x && fp_num1="0"
+  fp_version1="[$]*"
+
+  set dummy $fp_version2; shift
+  fp_num2=""
+  test $[@%:@] = 0 || { fp_num2="[$]1"; shift; }
+  test x"$fp_num2" = x && fp_num2="0"
+  fp_version2="[$]*"
+
+  test "$fp_num1" = "$fp_num2" || break;
+done
+IFS=$fp_save_IFS
+AS_IF([test "$fp_num1" $2 "$fp_num2"], [$4], [$5])[]dnl
+])# FP_COMPARE_VERSIONS
+
+
+dnl
+dnl Check for GreenCard and version.
+dnl
+AC_DEFUN([FPTOOLS_GREENCARD],
+[
+AC_PATH_PROG(GreenCardCmd,greencard)
+AC_CACHE_CHECK([for version of greencard], fptools_cv_greencard_version,
+changequote(, )dnl
+[if test x"$GreenCardCmd" != x; then
+   fptools_cv_greencard_version="`$GreenCardCmd --version |
+                         grep 'version' | sed -e 's/greencard. version \([^ ]*\).*/\1/g'`"
+else
+   fptools_cv_greencard_version=""
+fi
+changequote([, ])dnl
+])
+FP_COMPARE_VERSIONS([$fptools_cv_greencard_version],[-lt],[$1],
+  [AC_MSG_ERROR([greencard version $1 or later is required (found '$fptools_cv_greencard_version')])])[]dnl
+GreenCardVersion=$fptools_cv_greencard_version
+AC_SUBST(GreenCardVersion)
 ])
 
 dnl
 dnl Check for Happy and version.  If we're building GHC, then we need
-dnl at least Happy version 1.6.  If there's no installed Happy, we look
+dnl at least Happy version 1.14.  If there's no installed Happy, we look
 dnl for a happy source tree and point the build system at that instead.
 dnl
-dnl ToDo: when we reset HappyCmd to the source tree, autoconf doesn't
-dnl seems to insert it in the cache file.  sigh.
-dnl
-AC_DEFUN(FPTOOLS_HAPPY,
-[AC_PATH_PROG(HappyCmd,happy)
+AC_DEFUN([FPTOOLS_HAPPY],
+[AC_PATH_PROG(HappyCmd,happy,)
 AC_CACHE_CHECK([for version of happy], fptools_cv_happy_version,
+changequote(, )dnl
 [if test x"$HappyCmd" != x; then
    fptools_cv_happy_version="`$HappyCmd -v |
-changequote(, )dnl
                          grep 'Happy Version' | sed -e 's/Happy Version \([^ ]*\).*/\1/g'`" ;
-elif test -d $srcdir/happy; then
-   HappyCmd=$hardtop/happy/src/happy-inplace;
-   fptools_cv_happy_version=`grep '^ProjectVersion[    ]*=' $srcdir/happy/mk/version.mk | sed 's/.*\([0-9][0-9]*\.[0-9][0-9]*\).*/\1/g'`;
-   echo -n "using happy from the source tree... ";
 else
    fptools_cv_happy_version="";
 fi;
 changequote([, ])dnl
-if expr "$fptools_cv_happy_version" "<" 1.6 > /dev/null 2>&1; then
-   if test -d $srcdir/ghc; then
-     echo
-     echo "Happy version 1.6 or later is required to compile GHC."
-     exit 1;
-   fi
-fi;
 ])
+if test ! -f compiler/parser/Parser.hs || test ! -f compiler/main/ParsePkgConf.hs || test ! -f compiler/cmm/CmmParse.hs || test ! -f compiler/parser/ParserCore.hs
+then
+    FP_COMPARE_VERSIONS([$fptools_cv_happy_version],[-lt],[1.15],
+      [AC_MSG_ERROR([Happy version 1.15 or later is required to compile GHC.])])[]dnl
+fi
 HappyVersion=$fptools_cv_happy_version;
 AC_SUBST(HappyVersion)
 ])
 
 dnl
-dnl What's the best way of doing context diffs?
-dnl
-dnl (NB: NeXTStep thinks diff'ing a file against itself is "trouble")
+dnl Check for Haddock and version.  If there's no installed Haddock, we look
+dnl for a haddock source tree and point the build system at that instead.
 dnl
-AC_DEFUN(FPTOOLS_PROG_DIFF,
-[AC_CACHE_CHECK([for ok way to do context diffs], fptools_cv_context_diffs,
-[echo foo > conftest1
-echo foo > conftest2
-if diff -C 1 conftest1 conftest2 > /dev/null 2>&1 ; then
-    fptools_cv_context_diffs='diff -C 1'
-else
-    if diff -c1 conftest1 conftest2 > /dev/null 2>&1 ; then
-        fptools_cv_context_diffs='diff -c1'
-    else
-        echo "Can't figure out how to do context diffs."
-        echo "Neither \`diff -C 1' nor \`diff -c1' works."
-        exit 1
-    fi
-fi
-rm -f conftest1 conftest2
-])
-ContextDiffCmd=$fptools_cv_context_diffs
-AC_SUBST(ContextDiffCmd)
+AC_DEFUN([FPTOOLS_HADDOCK],
+[AC_PATH_PROG(HaddockCmd,haddock,)
+dnl Darn, I forgot to make Haddock print out its version number when
+dnl invoked with -v.  We could try generating some HTML and grepping
+dnl through that to find the version number, but I think we'll make
+dnl do without it for now.
 ])
 
 dnl
-dnl Finding the Right Yacc
+dnl Check for Alex and version.  If we're building GHC, then we need
+dnl at least Alex version 2.0.1.
 dnl
-AC_DEFUN(FPTOOLS_PROG_YACCY,
-[AC_PROG_YACC
-if test "$YACC" = "yacc"; then
-   AC_CACHE_CHECK([if it is an OK yacc], ac_cv_prog_yacc,
-   [AC_CHECK_PROG(WhatCmd, what, what, :)
-    $WhatCmd $YACC > conftest.out
-    if egrep 'y1\.c 1\..*SMI' conftest.out >/dev/null 2>&1; then
-        echo "I don't trust your $YaccCmd; it looks like an old Sun yacc"
-        if test -f /usr/lang/yacc; then
-           echo "I'm going to use /usr/lang/yacc instead"
-           ac_cv_prog_yacc=/usr/lang/yacc
-        else
-           echo "I'm assuming the worst...no parser generator at all"
-           ac_cv_prog_yacc=:
-        fi
-    elif egrep 'y1\.c.*Revision: 4\.2\.6\.3.*DEC' conftest.out >/dev/null 2>&1; then
-        echo "I don't trust your $YaccCmd; it looks like a lame DEC yacc"
-        echo "I'm assuming the worst...no parser generator at all"
-        ac_cv_prog_yacc=:
-    else
-       ac_cv_prog_yacc=$YACC
-    fi
-    rm -fr conftest*
-])
+AC_DEFUN([FPTOOLS_ALEX],
+[
+AC_PATH_PROG(AlexCmd,alex,)
+AC_CACHE_CHECK([for version of alex], fptools_cv_alex_version,
+changequote(, )dnl
+[if test x"$AlexCmd" != x; then
+   fptools_cv_alex_version="`$AlexCmd -v |
+                         grep 'Alex [Vv]ersion' | sed -e 's/Alex [Vv]ersion \([0-9\.]*\).*/\1/g'`" ;
 else
-    ac_cv_prog_yacc=$YACC
+   fptools_cv_alex_version="";
+fi;
+changequote([, ])dnl
+])
+if test ! -f compiler/cmm/CmmLex.hs || test ! -f compiler/parser/Lexer.hs
+then
+    FP_COMPARE_VERSIONS([$fptools_cv_alex_version],[-lt],[2.0.1],
+      [AC_MSG_ERROR([Alex version 2.0.1 or later is required to compile GHC.])])[]dnl
 fi
-YaccCmd=$ac_cv_prog_yacc
-AC_SUBST(YaccCmd)
+AlexVersion=$fptools_cv_alex_version;
+AC_SUBST(AlexVersion)
 ])
 
-dnl *** Checking for ar and its arguments + whether we need ranlib.
-dnl
-dnl ArCmd and RANLIB are AC_SUBST'ed
-dnl 
-AC_DEFUN(FPTOOLS_PROG_AR_AND_RANLIB,
-[AC_PATH_PROG(ArCmd,ar)
-if test -z "$ArCmd"; then
-    echo "You don't seem to have ar in your PATH...I have no idea how to make a library"
-    exit 1;
+
+# FP_PROG_LD
+# ----------
+# Sets the output variable LdCmd to the (non-Cygwin version of the) full path
+# of ld. Exits if no ld can be found
+AC_DEFUN([FP_PROG_LD],
+[
+if test -z "$1"
+then
+  AC_PATH_PROG([fp_prog_ld_raw], [ld])
+  if test -z "$fp_prog_ld_raw"; then
+    AC_MSG_ERROR([cannot find ld in your PATH, no idea how to link])
+  fi
+  LdCmd=$fp_prog_ld_raw
+  case $HostPlatform in
+    *mingw32) if test x${OSTYPE} != xmsys; then
+             LdCmd="`cygpath -w ${fp_prog_ld_raw} | sed -e 's@\\\\@/@g'`"
+                AC_MSG_NOTICE([normalized ld command to $LdCmd])
+              fi
+           # Insist on >= ld-2.15.x, since earlier versions doesn't handle
+           # the generation of relocatable object files with large amounts
+           # of relocations correctly. (cf. HSbase.o splittage-hack)
+           fp_prog_ld_version=`${LdCmd} --version | sed -n '/GNU ld/p' | tr -cd 0-9 | cut -b1-3`
+           FP_COMPARE_VERSIONS([$fp_prog_ld_version],[-lt],[214],
+                                  [AC_MSG_ERROR([GNU ld version later than 2.14 required to compile GHC on Windows.])])[]dnl
+              ;;
+  esac
+else
+  LdCmd="$1"
 fi
-if $ArCmd clqs conftest.a >/dev/null 2>/dev/null; then
-    ArCmd="$ArCmd clqs"
-    NeedRanLib=''
-elif $ArCmd cqs conftest.a >/dev/null 2>/dev/null; then
-    ArCmd="$ArCmd cqs"
-    NeedRanLib=''
-elif $ArCmd clq conftest.a >/dev/null 2>/dev/null; then
-    ArCmd="$ArCmd clq"
-    NeedRanLib='YES'
-elif $ArCmd cq conftest.a >/dev/null 2>/dev/null; then
-    ArCmd="$ArCmd cq"
-    NeedRanLib='YES'
-elif $ArCmd cq conftest.a 2>&1 | grep 'no archive members specified' >/dev/null 2>/dev/null; then
-    ArCmd="$ArCmd cq"
-    NeedRanLib='YES'
+AC_SUBST([LdCmd])
+])# FP_PROG_LD
+
+
+# FP_PROG_LD_X
+# ------------
+# Sets the output variable LdXFlag to -x if ld supports this flag, otherwise the
+# variable's value is empty.
+AC_DEFUN([FP_PROG_LD_X],
+[AC_REQUIRE([FP_PROG_LD])
+AC_CACHE_CHECK([whether ld understands -x], [fp_cv_ld_x],
+[echo 'foo() {}' > conftest.c
+${CC-cc} -c conftest.c
+if ${LdCmd} -r -x -o conftest2.o conftest.o > /dev/null 2>&1; then
+   fp_cv_ld_x=yes
 else
-    echo "I can't figure out how to use your $ArCmd"
-    exit 1
+   fp_cv_ld_x=no
 fi
-rm -rf conftest*
-test -n "$ArCmd" && test -n "$verbose" && echo "        setting ArCmd to $ArCmd"
-AC_SUBST(ArCmd)
-if test -z "$NeedRanLib"; then
-    RANLIB=':'
-    test -n "$verbose" && echo "        setting RANLIB to $RANLIB"
-    AC_SUBST(RANLIB)
+rm -rf conftest*])
+if test "$fp_cv_ld_x" = yes; then
+  LdXFlag=-x
 else
-    AC_PROG_RANLIB
+  LdXFlag=
 fi
-])
+AC_SUBST([LdXFlag])
+])# FP_PROG_LD_X
+
+
+# FP_PROG_LD_IS_GNU
+# -----------------
+# Sets the output variable LdIsGNULd to YES or NO, depending on whether it is
+# GNU ld or not.
+AC_DEFUN([FP_PROG_LD_IS_GNU],
+[AC_REQUIRE([FP_PROG_LD])
+AC_CACHE_CHECK([whether ld is GNU ld], [fp_cv_gnu_ld],
+[if ${LdCmd} --version 2> /dev/null | grep "GNU" > /dev/null 2>&1; then
+  fp_cv_gnu_ld=yes
+else
+  fp_cv_gnu_ld=no
+fi])
+AC_SUBST([LdIsGNULd], [`echo $fp_cv_gnu_ld | sed 'y/yesno/YESNO/'`])
+])# FP_PROG_LD_IS_GNU
+
+
+# FP_PROG_AR
+# ----------
+# Sets fp_prog_ar_raw to the full path of ar and fp_prog_ar to a non-Cygwin
+# version of it. Exits if no ar can be found
+AC_DEFUN([FP_PROG_AR],
+[AC_PATH_PROG([fp_prog_ar_raw], [ar])
+if test -z "$fp_prog_ar_raw"; then
+  AC_MSG_ERROR([cannot find ar in your PATH, no idea how to make a library])
+fi
+fp_prog_ar=$fp_prog_ar_raw
+case $HostPlatform in
+  *mingw32) if test x${OSTYPE} != xmsys; then
+             fp_prog_ar="`cygpath -w ${fp_prog_ar_raw} | sed -e 's@\\\\@/@g'`"
+              AC_MSG_NOTICE([normalized ar command to $fp_prog_ar])
+            fi
+            ;;
+esac
+])# FP_PROG_AR
+
+
+# FP_PROG_AR_IS_GNU
+# -----------------
+# Sets fp_prog_ar_is_gnu to yes or no, depending on whether it is GNU ar or not.
+AC_DEFUN([FP_PROG_AR_IS_GNU],
+[AC_REQUIRE([FP_PROG_AR])
+AC_CACHE_CHECK([whether $fp_prog_ar_raw is GNU ar], [fp_cv_prog_ar_is_gnu],
+[if $fp_prog_ar_raw --version 2> /dev/null | grep "GNU" > /dev/null 2>&1; then
+  fp_cv_prog_ar_is_gnu=yes
+else
+  fp_cv_prog_ar_is_gnu=no
+fi])
+fp_prog_ar_is_gnu=$fp_cv_prog_ar_is_gnu
+])# FP_PROG_AR_IS_GNU
+
+
+# FP_PROG_AR_ARGS
+# ---------------
+# Sets fp_prog_ar_args to the arguments for ar and the output variable ArCmd
+# to a non-Cygwin invocation of ar including these arguments.
+AC_DEFUN([FP_PROG_AR_ARGS],
+[AC_REQUIRE([FP_PROG_AR_IS_GNU])
+AC_CACHE_CHECK([for ar arguments], [fp_cv_prog_ar_args],
+[
+# GNU ar needs special treatment: it appears to have problems with
+# object files with the same name if you use the 's' modifier, but
+# simple 'ar q' works fine, and doesn't need a separate ranlib.
+if test $fp_prog_ar_is_gnu = yes; then
+  fp_cv_prog_ar_args="q"
+else
+  touch conftest.dummy
+  for fp_var in clqsZ clqs cqs clq cq ; do
+     rm -f conftest.a
+     if $fp_prog_ar_raw $fp_var conftest.a conftest.dummy > /dev/null 2> /dev/null; then
+        fp_cv_prog_ar_args=$fp_var
+        break
+     fi
+  done
+  rm -f conftest*
+  if test -z "$fp_cv_prog_ar_args"; then
+    AC_MSG_ERROR([cannot figure out how to use your $fp_prog_ar_raw])
+  fi
+fi])
+fp_prog_ar_args=$fp_cv_prog_ar_args
+AC_SUBST([ArCmd], ["$fp_prog_ar $fp_prog_ar_args"])
+
+])# FP_PROG_AR_ARGS
+
+
+# FP_PROG_AR_NEEDS_RANLIB
+# -----------------------
+# Sets the output variable RANLIB to "ranlib" if it is needed and found,
+# to ":" otherwise.
+AC_DEFUN([FP_PROG_AR_NEEDS_RANLIB],
+[AC_REQUIRE([FP_PROG_AR_IS_GNU])
+AC_REQUIRE([FP_PROG_AR_ARGS])
+AC_REQUIRE([AC_PROG_CC])
+AC_CACHE_CHECK([whether ranlib is needed], [fp_cv_prog_ar_needs_ranlib],
+[if test $fp_prog_ar_is_gnu = yes; then
+  fp_cv_prog_ar_needs_ranlib=no
+elif echo $TargetPlatform | grep "^.*-apple-darwin$"  > /dev/null 2> /dev/null; then
+  # It's quite tedious to check for Apple's crazy timestamps in .a files,
+  # so we hardcode it.
+  fp_cv_prog_ar_needs_ranlib=yes
+elif echo $fp_prog_ar_args | grep "s" > /dev/null 2> /dev/null; then
+  fp_cv_prog_ar_needs_ranlib=no
+else
+  fp_cv_prog_ar_needs_ranlib=yes
+fi])
+if test $fp_cv_prog_ar_needs_ranlib = yes; then
+   AC_PROG_RANLIB
+else
+  RANLIB=":"
+  AC_SUBST([RANLIB])
+fi
+])# FP_PROG_AR_NEEDS_RANLIB
+
+
+# FP_PROG_AR_SUPPORTS_INPUT
+# -------------------------
+# Sets the output variable ArSupportsInput to "-input" or "", depending on
+# whether ar supports -input flag is supported or not.
+AC_DEFUN([FP_PROG_AR_SUPPORTS_INPUT],
+[AC_REQUIRE([FP_PROG_AR_IS_GNU])
+AC_REQUIRE([FP_PROG_AR_ARGS])
+AC_CACHE_CHECK([whether $fp_prog_ar_raw supports -input], [fp_cv_prog_ar_supports_input],
+[fp_cv_prog_ar_supports_input=no
+if test $fp_prog_ar_is_gnu = no; then
+  rm -f conftest*
+  touch conftest.lst
+  if FP_EVAL_STDERR([$fp_prog_ar_raw $fp_prog_ar_args conftest.a -input conftest.lst]) >/dev/null; then
+    test -s conftest.err || fp_cv_prog_ar_supports_input=yes
+  fi
+  rm -f conftest*
+fi])
+if test $fp_cv_prog_ar_supports_input = yes; then
+    ArSupportsInput="-input"
+else
+    ArSupportsInput=""
+fi
+AC_SUBST([ArSupportsInput])
+])# FP_PROG_AR_SUPPORTS_INPUT
+
 
 dnl
 dnl AC_SHEBANG_PERL - can we she-bang perl?
 dnl
-AC_DEFUN(FPTOOLS_SHEBANG_PERL,
+AC_DEFUN([FPTOOLS_SHEBANG_PERL],
 [AC_CACHE_CHECK([if your perl works in shell scripts], fptools_cv_shebang_perl,
 [echo "#!$PerlCmd"'
 exit $1;
@@ -287,310 +528,610 @@ fi
 rm -f conftest
 ])])
 
-dnl
-dnl Extra testing of the result AC_PROG_CC, testing the gcc version no.
-dnl *Must* be called after AC_PROG_CC
-dnl
-AC_DEFUN(FPTOOLS_HAVE_GCC,
-[AC_CACHE_CHECK([whether you have an ok gcc], fptools_cv_have_gcc,
-[if test -z "$GCC"; then
-    echo ''
-    echo "You would be better off with gcc"
-    echo "Perhaps it is already installed, but not in your PATH?"
-    fptools_cv_have_gcc='no'
+
+# FP_HAVE_GCC
+# -----------
+# Extra testing of the result AC_PROG_CC, testing the gcc version no. Sets the
+# output variables HaveGcc and GccVersion.
+AC_DEFUN([FP_HAVE_GCC],
+[AC_REQUIRE([AC_PROG_CC])
+if test -z "$GCC"; then
+   fp_have_gcc=NO
 else
-changequote(, )dnl
-    cmd_string="`$CC -v 2>&1 | grep 'version ' | sed -e 's/.*version [^0-9]*\([0-9][0-9]*\)\.\([0-9][0-9]*\).*/expr 20 \\\< \1 \\\* 10 + \2/g' `"
-changequote([, ])dnl
-    if test `eval $cmd_string 2>/dev/null` != "1"; then
-       echo ''
-        echo "I'm not sure if your version of gcc will work,"
-        echo "but it's worth a shot, eh?"
-    fi
-    fptools_cv_have_gcc='yes'
+   fp_have_gcc=YES
 fi
+if test "$fp_have_gcc" = "NO" -a -d $srcdir/ghc; then
+  AC_MSG_ERROR([gcc is required])
+fi
+AC_CACHE_CHECK([version of gcc], [fp_gcc_version],
+[if test "$fp_have_gcc" = "YES"; then
+   fp_gcc_version="`$CC -v 2>&1 | grep 'version ' | sed -e 's/.*version [[^0-9]]*\([[0-9.]]*\).*/\1/g'`"
+   FP_COMPARE_VERSIONS([$fp_gcc_version], [-lt], [2.0],
+     [AC_MSG_ERROR([Need at least gcc version 2.0 (3.4+ recommended)])])
+ else
+   fp_gcc_version="not-installed"
+ fi
 ])
-HaveGcc=`echo $fptools_cv_have_gcc | sed 'y/yesno/YESNO/'`
-AC_SUBST(HaveGcc)
+AC_SUBST([HaveGcc], [$fp_have_gcc])
+AC_SUBST([GccVersion], [$fp_gcc_version])
+])# FP_HAVE_GCC
+
+AC_DEFUN([FP_MINGW_GCC],
+[
+  case $HostOS_CPP in
+    mingw*)  AC_MSG_CHECKING([whether $CC is a mingw gcc])
+            if $CC -v 2>&1 | grep mingw >/dev/null; then
+               AC_MSG_RESULT([yes])
+            else
+               AC_MSG_RESULT([no])
+               AC_MSG_ERROR([Please use --with-gcc to specify a mingw gcc])
+            fi;;
+    *) ;;      
+  esac
 ])
 
 dnl Small feature test for perl version. Assumes PerlCmd
-dnl contains path to perl binary
+dnl contains path to perl binary.
 dnl
-AC_DEFUN(FPTOOLS_CHECK_PERL_VERSION,
+dnl (Perl versions prior to v5.6 does not contain the string "v5";
+dnl instead they display version strings such as "version 5.005".)
+dnl
+AC_DEFUN([FPTOOLS_CHECK_PERL_VERSION],
 [$PerlCmd -v >conftest.out 2>&1
-if grep "version 5" conftest.out >/dev/null 2>&1; then
-   :
-else
-   if grep "version 6" conftest.out >/dev/null 2>&1; then
+   if grep "v5" conftest.out >/dev/null 2>&1; then
       :
    else
-     echo "Your version of perl probably won't work."
+      AC_MSG_ERROR([your version of perl probably won't work, try upgrading it.])
    fi
-fi
 rm -fr conftest*
 ])
 
-dnl ** figure out the alignment restriction of a type
-dnl    (required SIZEOF test but AC_CHECK_SIZEOF doesn't call PROVIDE
-dnl     so we can't call REQUIRE)
-
-dnl FPTOOLS_CHECK_ALIGNMENT(TYPE)
-AC_DEFUN(FPTOOLS_CHECK_ALIGNMENT,
-[changequote(<<, >>)dnl
-dnl The name to #define.
-define(<<AC_TYPE_NAME>>, translit(alignment_$1, [a-z *], [A-Z_P]))dnl
-dnl The cache variable name.
-define(<<AC_CV_NAME>>, translit(ac_cv_alignment_$1, [ *], [_p]))dnl
-dnl The name of the corresponding size.
-define(<<AC_CV_SIZEOF_NAME>>, translit(ac_cv_sizeof_$1, [ *], [_p]))dnl
-changequote([, ])dnl
-AC_MSG_CHECKING(alignment of $1)
-AC_CACHE_VAL(AC_CV_NAME,
-[AC_TRY_RUN([
-#include <stdio.h>
-#if HAVE_STDDEF_H
-#include <stddef.h>
-#endif
-#ifndef offsetof
-#define offsetof(ty,field) ((size_t)((char *)&((ty *)0)->field - (char *)(ty *)0))
-#endif
-int
-main()
-{
-  FILE *f=fopen("conftestval", "w");
-  if (!f) exit(1);
-  fprintf(f, "%d\n", offsetof(struct { char c; $1 ty;},ty));
-  exit(0);
-}],
-AC_CV_NAME=`cat conftestval`,
-AC_CV_NAME=$AC_CV_SIZEOF_NAME,
-AC_CV_NAME=$AC_CV_SIZEOF_NAME)])
-AC_MSG_RESULT($AC_CV_NAME)
-AC_DEFINE_UNQUOTED(AC_TYPE_NAME, $AC_CV_NAME)
-AC_PROVIDE($AC_TYPE_NAME)
-undefine([AC_TYPE_NAME])dnl
-undefine([AC_CV_NAME])dnl
-undefine([AC_CV_SIZEOF_NAME])dnl
-])
 
-dnl ** figure out whether C compiler supports 'long long's
-dnl    (Closely based on Andreas Zeller's macro for testing
-dnl     for this under C++)
+# FP_CHECK_PROG(VARIABLE, PROG-TO-CHECK-FOR,
+#               [VALUE-IF-NOT-FOUND], [PATH], [REJECT])
+# -----------------------------------------------------
+# HACK: A small wrapper around AC_CHECK_PROG, setting VARIABLE to the full path
+# of PROG-TO-CHECK-FOR when found.
+AC_DEFUN([FP_CHECK_PROG],
+[AC_CHECK_PROG([$1], [$2], [$as_dir/$ac_word$ac_exec_ext], [$3], [$4], [$5])][]dnl
+)# FP_CHECK_PROC
+
+
+# FP_PROG_FIND
+# ------------
+# Find a non-WinDoze version of the "find" utility.
+AC_DEFUN([FP_PROG_FIND],
+[AC_PATH_PROG([fp_prog_find], [find])
+echo foo > conftest.txt
+$fp_prog_find conftest.txt -print > conftest.out 2>&1
+if grep '^conftest.txt$' conftest.out > /dev/null 2>&1 ; then
+  # OK, looks like a real "find".
+  case $HostPlatform in
+    *mingw32)
+      if test x${OSTYPE} != xmsys
+      then
+           fp_prog_find="`cygpath --mixed ${fp_prog_find}`"
+        AC_MSG_NOTICE([normalized find command to $fp_prog_find])
+      fi ;;
+    *) ;;
+  esac
+  FindCmd="$fp_prog_find"
+else
+  # Found a poor WinDoze version of "find", ignore it.
+  AC_MSG_WARN([$fp_prog_find looks like a non-*nix find, ignoring it])
+  FP_CHECK_PROG([FindCmd], [find], [], [], [$fp_prog_find])
+fi
+rm -f conftest.txt conftest.out
+AC_SUBST([FindCmd])[]dnl
+])# FP_PROG_FIND
+
+
+# FP_PROG_SORT
+# ------------
+# Find a Unix-like sort
+AC_DEFUN([FP_PROG_SORT],
+[AC_PATH_PROG([fp_prog_sort], [sort])
+echo conwip > conftest.txt
+$fp_prog_sort -f conftest.txt > conftest.out 2>&1
+if grep 'conwip' conftest.out > /dev/null 2>&1 ; then
+  # The goods
+  SortCmd="$fp_prog_sort"
+else
+  # Summink else..pick next one.
+  AC_MSG_WARN([$fp_prog_sort looks like a non-*nix sort, ignoring it])
+  FP_CHECK_PROG([SortCmd], [sort], [], [], [$fp_prog_sort])
+fi
+rm -f conftest.txt conftest.out
+AC_SUBST([SortCmd])[]dnl
+])# FP_PROG_SORT
+
 dnl
-dnl    If the C compiler supports `long long' types,
-dnl    define `HAVE_LONG_LONG'.
+dnl FPTOOLS_NOCACHE_CHECK prints a message, then sets the
+dnl values of the second argument to the result of running
+dnl the commands given by the third. It does not cache its
+dnl result, so it is suitable for checks which should be
+dnl run every time.
 dnl
-AC_DEFUN(FPTOOLS_C_LONG_LONG,
-[
-AC_REQUIRE([AC_PROG_CC])
-AC_MSG_CHECKING(whether ${CC} supports long long types)
-AC_CACHE_VAL(fptools_cv_have_long_long,
-[
-AC_LANG_SAVE
-AC_LANG_C
-AC_TRY_COMPILE(,[long long a;],
-fptools_cv_have_long_long=yes,
-fptools_cv_have_long_long=no)
-AC_LANG_RESTORE
-])
-AC_MSG_RESULT($fptools_cv_have_long_long)
-if test "$fptools_cv_have_long_long" = yes; then
-AC_DEFINE(HAVE_LONG_LONG)
-fi
+AC_DEFUN([FPTOOLS_NOCACHE_CHECK],
+[AC_MSG_CHECKING([$1])
+ $3
+ AC_MSG_RESULT([$][$2])
 ])
 
-dnl *** Can we open files in binary mode? ***
-dnl 
-AC_DEFUN(FPTOOLS_O_BINARY,
-[
-AC_REQUIRE([AC_PROG_CC])
-AC_MSG_CHECKING(whether we can open files in binary mode)
-AC_CACHE_VAL(fptools_cv_have_o_binary,
-[
-AC_LANG_SAVE
-AC_LANG_C
-AC_TRY_COMPILE(,
-[#ifdef HAVE_FCNTL_H
-#include <fcntl.h>
-#endif
-int x = O_BINARY;],
-fptools_cv_have_o_binary=yes,
-fptools_cv_have_o_binary=no)
-AC_LANG_RESTORE
-])
-AC_MSG_RESULT($fptools_cv_have_o_binary)
-if test "$fptools_cv_have_o_binary" = yes; then
-AC_DEFINE(HAVE_O_BINARY)
+dnl
+dnl FPTOOLS_GHC_VERSION(version)
+dnl FPTOOLS_GHC_VERSION(major, minor [, patchlevel])
+dnl FPTOOLS_GHC_VERSION(version, major, minor, patchlevel)
+dnl
+dnl Test for version of installed ghc.  Uses $GHC.
+dnl [original version pinched from c2hs]
+dnl
+AC_DEFUN([FPTOOLS_GHC_VERSION],
+[FPTOOLS_NOCACHE_CHECK([version of ghc], [fptools_version_of_ghc],
+["${WithGhc-ghc}" --version > conftestghc 2>&1
+  cat conftestghc >&AS_MESSAGE_LOG_FD
+#Useless Use Of cat award...
+  fptools_version_of_ghc=`cat conftestghc | sed -n -e 's/, patchlevel *\([[0-9]]\)/.\1/;s/.* version \([[0-9]][[0-9.]]*\).*/\1/p'`
+  rm -fr conftest*
+  if test "[$]fptools_version_of_ghc" = ""
+  then
+    fptools_version_of_ghc='unknown'
+  fi
+fptools_version_of_ghc[_major]=`echo [$]fptools_version_of_ghc | sed -e 's/^\([[0-9]]\).*/\1/'`
+fptools_version_of_ghc[_minor]=`echo [$]fptools_version_of_ghc | sed -e 's/^[[0-9]]\.\([[0-9]]*\).*/\1/'`
+fptools_version_of_ghc[_pl]=`echo [$]fptools_version_of_ghc | sed -n -e 's/^[[0-9]]\.[[0-9]]*\.\([[0-9]]*\)/\1/p'`
+#
+if test "[$]fptools_version_of_ghc[_pl]" = ""
+then
+  fptools_version_of_ghc[_all]="[$]fptools_version_of_ghc[_major].[$]fptools_version_of_ghc[_minor]"
+  fptools_version_of_ghc[_pl]="0"
+else
+  fptools_version_of_ghc[_all]="[$]fptools_version_of_ghc[_major].[$]fptools_version_of_ghc[_minor].[$]fptools_version_of_ghc[_pl]"
 fi
+#
+ifelse($#, [1], [dnl
+[$1]="[$]fptools_version_of_ghc[_all]"
+], $#, [2], [dnl
+[$1]="[$]fptools_version_of_ghc[_major]"
+[$2]="[$]fptools_version_of_ghc[_minor]"
+], $#, [3], [dnl
+[$1]="[$]fptools_version_of_ghc[_major]"
+[$2]="[$]fptools_version_of_ghc[_minor]"
+[$3]="[$]fptools_version_of_ghc[_pl]"
+], $#, [4], [dnl
+[$1]="[$]fptools_version_of_ghc[_all]"
+[$2]="[$]fptools_version_of_ghc[_major]"
+[$3]="[$]fptools_version_of_ghc[_minor]"
+[$4]="[$]fptools_version_of_ghc[_pl]"
 ])
+])
+])dnl
 
-dnl *** Which one comes first, .text or .data? ***
-dnl 
-AC_DEFUN(FPTOOLS_CODE_BEFORE_DATA,
-[AC_CACHE_CHECK([if code section appears before data], fptools_cv_code_bef_data,
-[AC_TRY_RUN([
-int f() { return 1; }
-int i;
-int main() { return ((char*)&f > (char*)&i); }
-
-],
-fptools_cv_code_bef_data=yes, fptools_cv_code_bef_data=no,false)])
-if test "$fptools_cv_code_bef_data" = yes; then
-  AC_DEFINE(CODE_BEFORE_DATA)
+
+# FP_CHECK_FUNC(FUNCTION, PROLOGUE, BODY, [ACTION-IF-FOUND], [ACTION-IF-NOT-FOUND])
+# ---------------------------------------------------------------------------------
+# A variant of AC_CHECK_FUNCS, limited to a single FUNCTION, but with the
+# additional flexibility of specifying the PROLOGUE and BODY.
+AC_DEFUN([FP_CHECK_FUNC],
+[AS_VAR_PUSHDEF([fp_func], [fp_cv_func_$1])dnl
+AC_CACHE_CHECK([for $1], fp_func,
+[AC_LINK_IFELSE([AC_LANG_PROGRAM([$2], [$3])],
+                [AS_VAR_SET(fp_func, yes)],
+                [AS_VAR_SET(fp_func, no)])])
+AS_IF([test AS_VAR_GET(fp_func) = yes],
+      [AC_DEFINE(AS_TR_CPP(HAVE_$1), [1],
+                [Define to 1 if you have the `]$1[' function.]) $4],
+      [$5])dnl
+AS_VAR_POPDEF([fp_func])dnl
+])# FP_CHECK_FUNC
+
+
+# FP_GEN_DOCBOOK_XML
+# ------------------
+# Generates a DocBook XML V4.2 document in conftest.xml.
+AC_DEFUN([FP_GEN_DOCBOOK_XML],
+[rm -f conftest.xml
+cat > conftest.xml << EOF
+<?xml version="1.0" encoding="iso-8859-1"?>
+<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
+   "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
+<book id="test">
+  <title>A DocBook Test Document</title>
+  <chapter id="id-one">
+    <title>A Chapter Title</title>
+    <para>This is a paragraph, referencing <xref linkend="id-two"/>.</para>
+  </chapter>
+  <chapter id="id-two">
+    <title>Another Chapter Title</title>
+    <para>This is another paragraph, referencing <xref linkend="id-one"/>.</para>
+  </chapter>
+</book>
+EOF
+]) # FP_GEN_DOCBOOK_XML
+
+
+# FP_PROG_XSLTPROC
+# ----------------
+# Sets the output variable XsltprocCmd to the full path of the XSLT processor
+# xsltproc. XsltprocCmd is empty if xsltproc could not be found.
+AC_DEFUN([FP_PROG_XSLTPROC],
+[AC_PATH_PROG([XsltprocCmd], [xsltproc])
+if test -z "$XsltprocCmd"; then
+  AC_MSG_WARN([cannot find xsltproc in your PATH, you will not be able to build the documentation])
 fi
-])
+])# FP_PROG_XSLTPROC
 
-dnl *** Helper function **
-dnl 
-AC_DEFUN(FPTOOLS_IN_SCOPE,AC_TRY_LINK([extern char* $1;],[return (int)&$2], $3=yes, $3=no))
 
-dnl *** What's the end-of-text-section marker called? ***
-dnl
-AC_DEFUN(FPTOOLS_END_TEXT_SECTION,
-[AC_MSG_CHECKING([for end of text section marker])
-not_done=1
-for i in data_start _data_start etext _etext __etext; do
-  FPTOOLS_IN_SCOPE($i,$i,fptools_end_of_text)
-  if test "$fptools_end_of_text" = yes; then
-   AC_CACHE_VAL([fptools_cv_end_of_text_decl], AC_DEFINE_UNQUOTED(TEXT_SECTION_END_MARKER_DECL, $i))
-   AC_CACHE_VAL([fptools_cv_end_of_text], AC_DEFINE_UNQUOTED(TEXT_SECTION_END_MARKER, $i))
-   not_done=0
-   break
-  fi
-done
-if test "$not_done" = 1; then
-FPTOOLS_IN_SCOPE(etext asm("etext"),etext,fptools_end_of_text);
-if test "$fptools_end_of_text" = yes; then
-  AC_CACHE_VAL([fptools_cv_end_of_text], AC_DEFINE_UNQUOTED(TEXT_SECTION_END_MARKER, etext))
-  AC_CACHE_VAL([fptools_cv_end_of_text_decl], AC_DEFINE_UNQUOTED(TEXT_SECTION_END_MARKER_DECL, etext asm("etext")))
+# FP_DIR_DOCBOOK_XSL(XSL-DIRS)
+# ----------------------------
+# Check which of the directories XSL-DIRS contains DocBook XSL stylesheets. The
+# output variable DIR_DOCBOOK_XSL will contain the first usable directory or
+# will be empty if none could be found.
+AC_DEFUN([FP_DIR_DOCBOOK_XSL],
+[AC_REQUIRE([FP_PROG_XSLTPROC])dnl
+if test -n "$XsltprocCmd"; then
+  AC_CACHE_CHECK([for DocBook XSL stylesheet directory], fp_cv_dir_docbook_xsl,
+  [FP_GEN_DOCBOOK_XML
+  fp_cv_dir_docbook_xsl=no
+  for fp_var in $1; do
+     if $XsltprocCmd ${fp_var}/html/docbook.xsl conftest.xml > /dev/null 2>&1; then
+        fp_cv_dir_docbook_xsl=$fp_var
+        break
+     fi
+  done
+  rm -rf conftest*])
+fi
+if test x"$fp_cv_dir_docbook_xsl" = xno; then
+  AC_MSG_WARN([cannot find DocBook XSL stylesheets, you will not be able to build the documentation])
+  DIR_DOCBOOK_XSL=
 else
-  AC_DEFINE_UNQUOTED(TEXT_SECTION_END_MARKER_DECL, dunno_what_it_is)
-  AC_DEFINE_UNQUOTED(TEXT_SECTION_END_MARKER, dunno_what_it_is)
+  DIR_DOCBOOK_XSL=$fp_cv_dir_docbook_xsl
 fi
+AC_SUBST([DIR_DOCBOOK_XSL])
+])# FP_DIR_DOCBOOK_XSL
+
+
+# FP_PROG_XMLLINT
+# ----------------
+# Sets the output variable XmllintCmd to the full path of the XSLT processor
+# xmllint. XmllintCmd is empty if xmllint could not be found.
+AC_DEFUN([FP_PROG_XMLLINT],
+[AC_PATH_PROG([XmllintCmd], [xmllint])
+if test -z "$XmllintCmd"; then
+  AC_MSG_WARN([cannot find xmllint in your PATH, you will not be able to validate your documentation])
 fi
-AC_MSG_RESULT([$]fptools_cv_end_of_text)
-])
+])# FP_PROG_XMLLINT
 
-dnl *** What's the end-of-data-section marker called? ***
-dnl
-AC_DEFUN(FPTOOLS_END_DATA_SECTION,
-[AC_MSG_CHECKING([for end of data section marker])
-not_done=1
-for i in end _end __end; do
-  FPTOOLS_IN_SCOPE($i,$i,fptools_end_of_data)
-  if test "$fptools_end_of_data" = yes; then
-   AC_CACHE_VAL([fptools_cv_end_of_data_decl], [AC_DEFINE_UNQUOTED(DATA_SECTION_END_MARKER_DECL, $i)])
-   AC_CACHE_VAL([fptools_cv_end_of_data], [AC_DEFINE_UNQUOTED(DATA_SECTION_END_MARKER, $i)])
-   not_done=0
-   break
+
+# FP_CHECK_DOCBOOK_DTD
+# --------------------
+AC_DEFUN([FP_CHECK_DOCBOOK_DTD],
+[AC_REQUIRE([FP_PROG_XMLLINT])dnl
+if test -n "$XmllintCmd"; then
+  AC_MSG_CHECKING([for DocBook DTD])
+  FP_GEN_DOCBOOK_XML
+  if $XmllintCmd --valid --noout conftest.xml > /dev/null 2>&1; then
+    AC_MSG_RESULT([ok])
+  else
+    AC_MSG_RESULT([failed])
+    AC_MSG_WARN([cannot find a DTD for DocBook XML V4.2, you will not be able to validate your documentation])
+    AC_MSG_WARN([check your XML_CATALOG_FILES environment variable and/or /etc/xml/catalog])
   fi
-done
-if test "$not_done" = 1; then
-FPTOOLS_IN_SCOPE(end asm("end"),end,fptools_end_of_data);
-if test "$fptools_end_of_data" = yes; then
-  AC_CACHE_VAL([fptools_cv_end_of_data_decl], [AC_DEFINE_UNQUOTED(DATA_SECTION_END_MARKER_DECL, end asm("end"))])
-  AC_CACHE_VAL([fptools_cv_end_of_data], [AC_DEFINE_UNQUOTED(DATA_SECTION_END_MARKER, end)])
-else
-  AC_CACHE_VAL([fptools_cv_end_of_data_decl], [AC_DEFINE_UNQUOTED(DATA_SECTION_END_MARKER_DECL, dunno_what_it_is)])
-  AC_CACHE_VAL([fptools_cv_end_of_data], [AC_DEFINE_UNQUOTED(DATA_SECTION_END_MARKER, dunno_what_it_is)])
+  rm -rf conftest*
 fi
-fi
-AC_MSG_RESULT([$]fptools_cv_end_of_data)
-])
+])# FP_CHECK_DOCBOOK_DTD
 
 
+# FP_GEN_FO
+# ------------------
+# Generates a formatting objects document in conftest.fo.
+AC_DEFUN([FP_GEN_FO],
+[rm -f conftest.fo
+cat > conftest.fo << EOF
+<?xml version="1.0"?>
+<fo:root xmlns:fo="http://www.w3.org/1999/XSL/Format">
+  <fo:layout-master-set>
+    <fo:simple-page-master master-name="blank">
+      <fo:region-body/>
+    </fo:simple-page-master>
+  </fo:layout-master-set>
+  <fo:page-sequence master-reference="blank">
+    <fo:flow flow-name="xsl-region-body">
+      <fo:block>
+        Test!
+      </fo:block>
+    </fo:flow>
+  </fo:page-sequence>
+</fo:root>
+EOF
+]) # FP_GEN_FO
+
 
-dnl Based on AC_TRY_LINK - run iftrue if links cleanly with no warning
+# FP_PROG_FOP
+# -----------
+# Set the output variable 'FopCmd' to the first working 'fop' in the current
+# 'PATH'. Note that /usr/bin/fop is broken in SuSE 9.1 (unpatched), so try
+# /usr/share/fop/fop.sh in that case (or no 'fop'), too.
+AC_DEFUN([FP_PROG_FOP],
+[AC_PATH_PROGS([FopCmd1], [fop fop.sh])
+if test -n "$FopCmd1"; then
+  AC_CACHE_CHECK([for $FopCmd1 usability], [fp_cv_fop_usability],
+    [FP_GEN_FO
+    if "$FopCmd1" -fo conftest.fo -ps conftest.ps > /dev/null 2>&1; then
+      fp_cv_fop_usability=yes
+    else
+      fp_cv_fop_usability=no
+    fi
+    rm -rf conftest*])
+  if test x"$fp_cv_fop_usability" = xyes; then
+     FopCmd=$FopCmd1
+  fi
+fi
+if test -z "$FopCmd"; then
+  AC_PATH_PROGS([FopCmd2], [fop.sh], , [/usr/share/fop])
+  FopCmd=$FopCmd2
+fi
+AC_SUBST([FopCmd])
+])# FP_PROG_FOP
 
-dnl FPTOOLS_TRY_LINK_NOWARN(flags,main?,iftrue,iffalse)
 
-AC_DEFUN(FPTOOLS_TRY_LINK_NOWARN,
-[
-ac_save_LIBS="$LIBS"
-LIBS=[$1];
-cat > conftest.$ac_ext <<EOF
-dnl This sometimes fails to find confdefs.h, for some reason.
-dnl [#]line __oline__ "[$]0"
-[#]line __oline__ "configure"
-#include "confdefs.h"
-[$2]
-int t() { return 0; }
-EOF
-if AC_TRY_EVAL(ac_link); then
-  ifelse([$3], , :, [
-    LIBS="$ac_save_LIBS"
-    rm -rf conftest*
-    $3])
-  ifelse([$4], , , [else
-    LIBS="$ac_save_LIBS"
-    rm -rf conftest*
-    $4
-])dnl
+# FP_PROG_FO_PROCESSOR
+# --------------------
+# Try to find an FO processor. PassiveTeX output is sometimes a bit strange, so
+# try FOP first. Sets the output variables FopCmd, XmltexCmd, DvipsCmd, and
+# PdfxmltexCmd.
+AC_DEFUN([FP_PROG_FO_PROCESSOR],
+[AC_REQUIRE([FP_PROG_FOP])
+AC_PATH_PROG([XmltexCmd], [xmltex])
+AC_PATH_PROG([DvipsCmd], [dvips])
+if test -z "$FopCmd"; then
+  if test -z "$XmltexCmd"; then
+    AC_MSG_WARN([cannot find an FO => DVI converter, you will not be able to build DVI or PostScript documentation])
+  else
+    if test -z "$DvipsCmd"; then
+      AC_MSG_WARN([cannot find a DVI  => PS converter, you will not be able to build PostScript documentation])
+    fi
+  fi
+  AC_PATH_PROG([PdfxmltexCmd], [pdfxmltex])
+  if test -z "$PdfxmltexCmd"; then
+    AC_MSG_WARN([cannot find an FO => PDF converter, you will not be able to build PDF documentation])
+  fi
+elif test -z "$XmltexCmd"; then
+  AC_MSG_WARN([cannot find an FO => DVI converter, you will not be able to build DVI documentation])
 fi
-rm -f conftest*
-]
-)
-
-dnl Loosely based on AC_CHECK_LIB in acgeneral.m4 in autoconf distribution
-
-dnl FPTOOLS_CHECK_FLAG_NOWARN(NAME, FLAG, CODE, iftrue, iffalse)
-
-AC_DEFUN(FPTOOLS_CHECK_FLAG_NOWARN,
-[AC_MSG_CHECKING([for $1])
- AC_CACHE_VAL(ac_cv_flag_$1,
-   [FPTOOLS_TRY_LINK_NOWARN("$2", [main() { $3; exit(0); } ],
-     eval "ac_cv_flag_$1=yes",
-     eval "ac_cv_flag_$1=no"
-   )]
- )
-if eval "test \"`echo '$ac_cv_flag_'$1`\" = yes"; then
-  AC_MSG_RESULT(yes)
-  LIBS="$2 $LIBS"
-  $4
+])# FP_PROG_FO_PROCESSOR
+
+
+# FP_PROG_GHC_PKG
+# ----------------
+# Try to find a ghc-pkg matching the ghc mentioned in the environment variable
+# WithGhc. If the latter is unset or no matching ghc-pkg can be found, try to
+# find a plain ghc-pkg. Sets the output variable GhcPkgCmd.
+AC_DEFUN([FP_PROG_GHC_PKG],
+[AC_CACHE_CHECK([for ghc-pkg matching $WithGhc], fp_cv_matching_ghc_pkg,
+[fp_ghc_pkg_guess=`echo $WithGhc | sed 's,ghc\(@<:@^/\\@:>@*\)$,ghc-pkg\1,'`
+if "$fp_ghc_pkg_guess" -l > /dev/null 2>&1; then
+  fp_cv_matching_ghc_pkg=$fp_ghc_pkg_guess
 else
-  AC_MSG_RESULT(no)
-  $5
-fi
+  fp_cv_matching_ghc_pkg=no
+fi])
+if test x"$fp_cv_matching_ghc_pkg" = xno; then
+  AC_PATH_PROG([GhcPkgCmd], [ghc-pkg])
+else
+  GhcPkgCmd=$fp_cv_matching_ghc_pkg
+fi])# FP_PROG_GHC_PKG
+
+
+# FP_GHC_HAS_READLINE
+# -------------------
+AC_DEFUN([FP_GHC_HAS_READLINE],
+[AC_REQUIRE([FP_PROG_GHC_PKG])
+AC_CACHE_CHECK([whether ghc has readline package], [fp_cv_ghc_has_readline],
+[if "${GhcPkgCmd-ghc-pkg}" --show-package readline >/dev/null 2>&1; then
+  fp_cv_ghc_has_readline=yes
+else
+  fp_cv_ghc_has_readline=no
+ fi])
+AC_SUBST([GhcHasReadline], [`echo $fp_cv_ghc_has_readline | sed 'y/yesno/YESNO/'`])
+])# FP_GHC_HAS_READLINE
+
+
+# FP_GCC_EXTRA_FLAGS
+# ------------------
+# Determine which extra flags we need to pass gcc when we invoke it
+# to compile .hc code.
+#
+# Some OSs (Mandrake Linux, in particular) configure GCC with
+# -momit-leaf-frame-pointer on by default. If this is the case, we
+# need to turn it off for mangling to work. The test is currently a
+# bit crude, using only the version number of gcc.
+# 
+# -fwrapv is needed for gcc to emit well-behaved code in the presence of
+# integer wrap around. (Trac #952)
+#
+# -fno-unit-at-a-time or -fno-toplevel-reoder is necessary to avoid gcc
+# reordering things in the module and confusing the manger and/or splitter.
+# (eg. Trac #1427)
+#
+AC_DEFUN([FP_GCC_EXTRA_FLAGS],
+[AC_REQUIRE([FP_HAVE_GCC])
+AC_CACHE_CHECK([for extra options to pass gcc when compiling via C], [fp_cv_gcc_extra_opts],
+[fp_cv_gcc_extra_opts=
+ FP_COMPARE_VERSIONS([$fp_gcc_version], [-ge], [3.4],
+  [fp_cv_gcc_extra_opts="$fp_cv_gcc_extra_opts -fwrapv"],
+  [])
+ case $TargetPlatform in
+  i386-*|x86_64-*) 
+     FP_COMPARE_VERSIONS([$fp_gcc_version], [-ge], [3.2],
+      [fp_cv_gcc_extra_opts="$fp_cv_gcc_extra_opts -mno-omit-leaf-frame-pointer"],
+      [])
+    FP_COMPARE_VERSIONS([$fp_gcc_version], [-ge], [3.4],
+     [FP_COMPARE_VERSIONS([$fp_gcc_version], [-ge], [4.2],
+       [fp_cv_gcc_extra_opts="$fp_cv_gcc_extra_opts -fno-toplevel-reorder"],
+       [fp_cv_gcc_extra_opts="$fp_cv_gcc_extra_opts -fno-unit-at-a-time"]
+     )],
+     [])
+  ;;
+ esac
+])
+AC_SUBST([GccExtraViaCOpts],$fp_cv_gcc_extra_opts)
 ])
 
-dnl FPTOOLS_CHECK_LIB_NOWARN(LIBRARY, FUNCTION)
-
-AC_DEFUN(FPTOOLS_CHECK_LIB_NOWARN,
-[FPTOOLS_CHECK_FLAG_NOWARN([function_$2],[],[extern char $2(); $2();],
-[changequote(, )dnl
-  ac_tr_lib=HAVE_LIB`echo $1 | tr 'abcdefghijklmnopqrstuvwxyz' 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'`
- changequote([, ])dnl
- AC_DEFINE_UNQUOTED($ac_tr_lib)
-],
-[FPTOOLS_CHECK_FLAG_NOWARN([library_$1],[-l$1],[extern char $2(); $2();],
-[changequote(, )dnl
-  ac_tr_lib=HAVE_LIB`echo $1 | tr 'abcdefghijklmnopqrstuvwxyz' 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'`
- changequote([, ])dnl
- AC_DEFINE_UNQUOTED($ac_tr_lib)
-],
-[]
-)])]
-)
-
-dnl check for prototypes
-dnl
-AC_DEFUN(AC_C_PROTOTYPES,
-[AC_CACHE_CHECK([prototypes], ac_cv_prototypes,
-[AC_TRY_COMPILE([
-void foo(int);
-void foo(i)
-int i; { 
-return;
-}
-],
-[int i;], 
-ac_cv_prototypes=yes,
-ac_cv_prototypes=no)])
-if test "$ac_cv_prototypes" = yes; then
-AC_DEFINE(HAVE_PROTOTYPES)
+
+# FP_SETUP_PROJECT_VERSION
+# ---------------------
+AC_DEFUN([FP_SETUP_PROJECT_VERSION],
+[
+if test "$RELEASE" = "NO"; then
+    AC_MSG_CHECKING([for GHC version date])
+    if test -f VERSION_DATE; then
+        PACKAGE_VERSION=${PACKAGE_VERSION}.`cat VERSION_DATE`
+        AC_MSG_RESULT(given $PACKAGE_VERSION)
+    elif test -d _darcs; then
+        changequote(, )dnl
+        ver_date=`darcs changes --quiet --no-summary --xml | head -500 | grep 'date=' | sed "s/^.*date='\([0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]\).*$/\1/g" | sort -n | tail -1`
+        if echo $ver_date | grep '^[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]$' 2>&1 >/dev/null; then true; else
+        changequote([, ])dnl
+                AC_MSG_ERROR([failed to detect version date: check that darcs is in your path])
+        fi
+        PACKAGE_VERSION=${PACKAGE_VERSION}.$ver_date
+        AC_MSG_RESULT(inferred $PACKAGE_VERSION)
+    elif test -f VERSION; then
+        PACKAGE_VERSION=`cat VERSION`
+        AC_MSG_RESULT(given $PACKAGE_VERSION)
+    else
+        AC_MSG_WARN([cannot determine snapshot version: no _darcs directory and no VERSION file])
+    fi
 fi
+
+# Some renamings
+AC_SUBST([ProjectName], [$PACKAGE_NAME])
+AC_SUBST([ProjectVersion], [$PACKAGE_VERSION])
+
+# Split PACKAGE_VERSION into (possibly empty) parts
+VERSION_MAJOR=`echo $PACKAGE_VERSION | sed 's/^\(@<:@^.@:>@*\)\(\.\{0,1\}\(.*\)\)$/\1'/`
+VERSION_TMP=`echo $PACKAGE_VERSION | sed 's/^\(@<:@^.@:>@*\)\(\.\{0,1\}\(.*\)\)$/\3'/`
+VERSION_MINOR=`echo $VERSION_TMP | sed 's/^\(@<:@^.@:>@*\)\(\.\{0,1\}\(.*\)\)$/\1'/`
+ProjectPatchLevel=`echo $VERSION_TMP | sed 's/^\(@<:@^.@:>@*\)\(\.\{0,1\}\(.*\)\)$/\3'/`
+
+# Calculate project version as an integer, using 2 digits for minor version
+case $VERSION_MINOR in
+  ?) ProjectVersionInt=${VERSION_MAJOR}0${VERSION_MINOR} ;;
+  ??) ProjectVersionInt=${VERSION_MAJOR}${VERSION_MINOR} ;;
+  *) AC_MSG_ERROR([bad minor version in $PACKAGE_VERSION]) ;;
+esac
+AC_SUBST([ProjectVersionInt])
+
+# The project patchlevel is zero unless stated otherwise
+test -z "$ProjectPatchLevel" && ProjectPatchLevel=0
+
+# Remove dots from the patch level; this allows us to have versions like 6.4.1.20050508
+ProjectPatchLevel=`echo $ProjectPatchLevel | sed 's/\.//'`
+
+AC_SUBST([ProjectPatchLevel])
+])# FP_SETUP_PROJECT_VERSION
+
+AC_DEFUN([FP_CHECK_TIMER_CREATE],
+  [AC_CACHE_CHECK([for a working timer_create(CLOCK_REALTIME)], 
+    [fptools_cv_timer_create_works],
+    [AC_TRY_RUN([
+#ifdef HAVE_TIME_H
+#include <time.h>
+#endif
+#ifdef HAVE_SIGNAL_H
+#include <signal.h>
+#endif
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+int main(int argc, char *argv[])
+{
+#if HAVE_TIMER_CREATE && HAVE_TIMER_SETTIME
+    struct sigevent ev;
+    timer_t timer;
+    ev.sigev_notify = SIGEV_SIGNAL;
+    ev.sigev_signo  = SIGVTALRM;
+    if (timer_create(CLOCK_PROCESS_CPUTIME_ID, &ev, &timer) != 0) {
+       exit(1);
+    }
+#else
+    exit(1)
+#endif
+    exit(0);
+}
+     ],
+     [fptools_cv_timer_create_works=yes],
+     [fptools_cv_timer_create_works=no])
+  ])
+case $fptools_cv_timer_create_works in
+    yes) AC_DEFINE([USE_TIMER_CREATE], 1, 
+                   [Define to 1 if we can use timer_create(CLOCK_PROCESS_CPUTIME_ID,...)]);;
+esac
 ])
 
+# FP_ARG_GMP
+# -------------
+AC_DEFUN([FP_ARG_GMP],
+[
+AC_ARG_WITH([gmp-includes],
+  [AC_HELP_STRING([--with-gmp-includes],
+    [directory containing gmp.h])],
+    [gmp_includes=$withval],
+    [gmp_includes=NONE])
+
+AC_ARG_WITH([gmp-libraries],
+  [AC_HELP_STRING([--with-gmp-libraries],
+    [directory containing gmp library])],
+    [gmp_libraries=$withval],
+    [gmp_libraries=NONE])
+])# FP_ARG_GMP
+
+AC_DEFUN([CHECK_GMP],
+[AC_REQUIRE([AC_PROG_CPP])
+AC_REQUIRE([AC_PROG_CC])
+])
+
+# --------------------------------------------------------------
+# Calculate absolute path to build tree
+# --------------------------------------------------------------
+
+AC_DEFUN([FP_FIND_ROOT],[
+AC_MSG_CHECKING(for path to top of build tree)
+
+dnl This would be
+dnl     make -C utils/pwd clean && make -C utils/pwd
+dnl except we don't want to have to know what make is called. Sigh.
+if test ! -f utils/pwd/pwd && test ! -f utils/pwd/pwd.exe; then
+  cd utils/pwd
+  rm -f *.o
+  rm -f *.hi
+  rm -f pwd
+  rm -f pwd.exe
+  $WithGhc -v0 --make pwd -o pwd
+  cd ../..
+fi
+
+hardtop=`utils/pwd/pwd forwardslash`
+
+if ! test -d "$hardtop"; then
+  AC_MSG_ERROR([cannot determine current directory])
+fi   
+
+dnl Remove common automounter nonsense
+dnl
+hardtop=`echo $hardtop | sed 's|^/tmp_mnt.*\(/local/.*\)$|\1|' | sed 's|^/tmp_mnt/|/|'`
+
+AC_SUBST(hardtop)
+
+AC_MSG_RESULT(${hardtop})
+
+# We don't support building in directories with spaces.
+case "$hardtop" in
+  *' '*) AC_MSG_ERROR([
+   The build system does not support building in a directory containing
+   space characters.  Suggestion: move the build tree somewhere else.])
+ ;;
+esac
+])
 
 # LocalWords:  fi