[project @ 2000-04-23 13:27:04 by chak]
[ghc-hetmet.git] / aclocal.m4
index 84a17e8..7d4e52b 100644 (file)
@@ -1,13 +1,39 @@
-#
-# extra autoconf macros for Glasgow fptools distribution
-#
-
-#
-# Has timezone the type time_t or long (HP-UX 10.20 apparently
-# has `long'..)
-#
-AC_DEFUN(AC_TYPE_TIMEZONE,
-[AC_CACHE_CHECK([type of timezone], ac_cv_type_timezone,
+dnl $Id: aclocal.m4,v 1.46 1999/12/21 13:00:54 simonmar 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.
+
+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
+])
+
+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>
@@ -19,17 +45,16 @@ AC_DEFUN(AC_TYPE_TIMEZONE,
 # endif
 #endif
 
-extern time_t timezone;
+extern time_t timezone;        
 ],
-[int i;], ac_cv_type_timezone=time_t, ac_cv_type_timezone=long)])
-AC_DEFINE_UNQUOTED(TYPE_TIMEZONE, $ac_cv_type_timezone)
+[int i;], fptools_cv_type_timezone=time_t, fptools_cv_type_timezone=long)])
+AC_DEFINE_UNQUOTED(TYPE_TIMEZONE, $fptools_cv_type_timezone)
 ])
 
-#
-# Is altzone available?
-#
-AC_DEFUN(AC_ALTZONE,
-[AC_CACHE_CHECK([altzone], ac_cv_altzone,
+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>
@@ -41,28 +66,49 @@ AC_DEFUN(AC_ALTZONE,
 # endif
 #endif
 ], [return altzone;], 
-ac_cv_altzone=yes, ac_cv_altzone=no)])
-if test "$ac_cv_altzone" = yes; then
+fptools_cv_altzone=yes, fptools_cv_altzone=no)])
+if test "$fptools_cv_altzone" = yes; then
   AC_DEFINE(HAVE_ALTZONE)
 fi
 ])
 
-#
+
 dnl ** check for leading underscores in symbol names
-#
-# Test for determining whether symbol names have a leading
-# underscore.
-#
-# We assume that they _haven't_ if anything goes wrong.
-#
-AC_DEFUN(AC_UNDERSCORE,
-[AC_CHECK_LIB(elf, elf_begin, LIBS="-lelf $LIBS")dnl
-AC_CACHE_CHECK([leading underscore in symbol names], ac_cv_lead_uscore,
+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,
+
+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
+<<
+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
 #include <nlist.h>
 changequote(<<, >>)dnl
 <<
-struct nlist xYzzY[] = {{"_xYzzY", 0},{0}};
+struct nlist xYzzY1[] = {{"xYzzY1", 0},{0}};
+struct nlist xYzzY2[] = {{"_xYzzY2", 0},{0}};
 #endif
 
 main(argc, argv)
@@ -70,23 +116,494 @@ int argc;
 char **argv;
 {
 #ifdef HAVE_NLIST_H
-    if(nlist(argv[0], xYzzY) == 0 && xYzzY[0].n_value != 0)
+    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
 #endif
     exit(1);
-}], ac_cv_lead_uscore=yes, ac_cv_lead_uscore=no, ac_cv_lead_uscore=NO)),
-#
-# Hack!: nlist() under Digital UNIX insist on there being an _,
-# but symbol table listings show none. What is going on here?!?
-#
-if test $HostPlatform = "alpha-dec-osf1"; then
-   LeadingUnderscore=NO
+}], fptools_cv_lead_uscore=yes, fptools_cv_lead_uscore=no, fptools_cv_lead_uscore=NO)
+;;
+esac);
+LeadingUnderscore=`echo $fptools_cv_lead_uscore | sed 'y/yesno/YESNO/'`
+AC_SUBST(LeadingUnderscore)
+case $LeadingUnderscore in
+YES) AC_DEFINE(LEADING_UNDERSCORE);;
+esac
+])
+
+dnl
+dnl Check for Happy and version.  If we're building GHC, then we need
+dnl at least Happy version 1.6.  If there's no installed Happy, we look
+dnl for a happy source tree and point the build system at that instead.
+dnl
+dnl ToDo: when we reset HappyCmd to the source tree, autoconf doesn't
+dnl seems to insert it in the cache file.  sigh.
+dnl
+AC_DEFUN(FPTOOLS_HAPPY,
+[AC_PATH_PROG(HappyCmd,happy)
+AC_CACHE_CHECK([for version of happy], fptools_cv_happy_version,
+[if test x"$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
-   LeadingUnderscore=`echo $ac_cv_lead_uscore | sed 'y/yesno/YESNO/'`
+   fptools_cv_happy_version="";
 fi;
-test -n "$verbose" && echo "    setting LeadingUnderscore to $LeadingUnderscore"
-AC_SUBST(LeadingUnderscore)
+changequote([, ])dnl
+if expr "$fptools_cv_happy_version" "<" 1.6 > /dev/null 2>&1; then
+   if test -d $srcdir/ghc; then
+     echo
+     echo "Happy version 1.6 or later is required to compile GHC."
+     exit 1;
+   fi
+fi;
+])
+HappyVersion=$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
+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=$fptools_cv_context_diffs
+AC_SUBST(ContextDiffCmd)
+])
+
+dnl
+dnl Finding the Right Yacc
+dnl
+AC_DEFUN(FPTOOLS_PROG_YACCY,
+[AC_PROG_YACC
+if test "$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*
+])
+else
+    ac_cv_prog_yacc=$YACC
+fi
+YaccCmd=$ac_cv_prog_yacc
+AC_SUBST(YaccCmd)
+])
+
+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;
+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'
+else
+    echo "I can't figure out how to use your $ArCmd"
+    exit 1
+fi
+rm -rf conftest*
+test -n "$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 $RANLIB"
+    AC_SUBST(RANLIB)
+else
+    AC_PROG_RANLIB
+fi
+])
+
+dnl
+dnl AC_SHEBANG_PERL - can we she-bang perl?
+dnl
+AC_DEFUN(FPTOOLS_SHEBANG_PERL,
+[AC_CACHE_CHECK([if your perl works in shell scripts], fptools_cv_shebang_perl,
+[echo "#!$PerlCmd"'
+exit $1;
+' > conftest
+chmod u+x conftest
+(SHELL=/bin/sh; export SHELL; ./conftest 69 > /dev/null)
+if test $? -ne 69; then
+   fptools_cv_shebang_perl=yes
+else
+   fptools_cv_shebang_perl=no
+fi
+rm -f conftest
+])])
+
+dnl
+dnl Extra testing of the result AC_PROG_CC, testing the gcc version no.
+dnl *Must* be called after AC_PROG_CC
+dnl
+AC_DEFUN(FPTOOLS_HAVE_GCC,
+[AC_CACHE_CHECK([whether you have an ok gcc], fptools_cv_have_gcc,
+[if test -z "$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'
+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'
+fi
+])
+HaveGcc=`echo $fptools_cv_have_gcc | sed 'y/yesno/YESNO/'`
+AC_SUBST(HaveGcc)
+])
+
+dnl Small feature test for perl version. Assumes PerlCmd
+dnl contains path to perl binary
+dnl
+AC_DEFUN(FPTOOLS_CHECK_PERL_VERSION,
+[$PerlCmd -v >conftest.out 2>&1
+if grep "version 4" conftest.out >/dev/null 2>&1; then
+   if grep "Patch level: 35" conftest.out >/dev/null 2>&1; then
+      echo "
+************************************************************************
+Uh-oh...looks like you have Perl 4.035.
+
+Perl version 4.035 has a bug to do with recursion that will bite if
+you run the lit2texi script, when making Info files from
+literate files of various sorts.  Either use perl5, the last version of perl4 
+(4.036), or an older version (e.g., perl 4.019). Failing that, don't create
+any Info files :-)
+************************************************************************
+"
+   fi
+else
+   if grep "version 5" conftest.out >/dev/null 2>&1; then
+      :
+   else
+     echo "I'm not sure if your version of perl will work,"
+     echo "but it's worth a shot, eh?"
+   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++)
+dnl
+dnl    If the C compiler supports `long long' types,
+dnl    define `HAVE_LONG_LONG'.
+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 "$fptools_cv_have_long_long" = yes; then
+AC_DEFINE(HAVE_LONG_LONG)
+fi
+])
+
+dnl *** Can we open files in binary mode? ***
+dnl 
+AC_DEFUN(FPTOOLS_O_BINARY,
+[
+AC_REQUIRE([AC_PROG_CC])
+AC_MSG_CHECKING(whether we can open files in binary mode)
+AC_CACHE_VAL(fptools_cv_have_o_binary,
+[
+AC_LANG_SAVE
+AC_LANG_C
+AC_TRY_COMPILE(,
+[#ifdef HAVE_FCNTL_H
+#include <fcntl.h>
+#endif
+int x = O_BINARY;],
+fptools_cv_have_o_binary=yes,
+fptools_cv_have_o_binary=no)
+AC_LANG_RESTORE
+])
+AC_MSG_RESULT($fptools_cv_have_o_binary)
+if test "$fptools_cv_have_o_binary" = yes; then
+AC_DEFINE(HAVE_O_BINARY)
+fi
+])
+
+dnl *** Which one comes first, .text or .data? ***
+dnl 
+AC_DEFUN(FPTOOLS_CODE_BEFORE_DATA,
+[AC_CACHE_CHECK([if code section appears before data], fptools_cv_code_bef_data,
+[AC_TRY_RUN([
+int f() { return 1; }
+int i;
+int main() { return ((char*)&f > (char*)&i); }
+
+],
+fptools_cv_code_bef_data=yes, fptools_cv_code_bef_data=no,false)])
+if test "$fptools_cv_code_bef_data" = yes; then
+  AC_DEFINE(CODE_BEFORE_DATA)
+fi
+])
+
+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 "$fptools_end_of_text" = yes; then
+  AC_CACHE_VAL([fptools_cv_end_of_text], AC_DEFINE_UNQUOTED(TEXT_SECTION_END_MARKER, etext))
+  AC_CACHE_VAL([fptools_cv_end_of_text_decl], AC_DEFINE_UNQUOTED(TEXT_SECTION_END_MARKER_DECL, etext asm("etext")))
+else
+  AC_DEFINE_UNQUOTED(TEXT_SECTION_END_MARKER_DECL, dunno_what_it_is)
+  AC_DEFINE_UNQUOTED(TEXT_SECTION_END_MARKER, dunno_what_it_is)
+fi
+fi
+AC_MSG_RESULT([$]fptools_cv_end_of_text)
+])
+
+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, $i)])
+   not_done=0
+   break
+  fi
+done
+if test "$not_done" = 1; then
+FPTOOLS_IN_SCOPE(end asm("end"),end,fptools_end_of_data);
+if test "$fptools_end_of_data" = yes; then
+  AC_CACHE_VAL([fptools_cv_end_of_data_decl], [AC_DEFINE_UNQUOTED(DATA_SECTION_END_MARKER_DECL, end asm("end"))])
+  AC_CACHE_VAL([fptools_cv_end_of_data], [AC_DEFINE_UNQUOTED(DATA_SECTION_END_MARKER, end)])
+else
+  AC_CACHE_VAL([fptools_cv_end_of_data_decl], [AC_DEFINE_UNQUOTED(DATA_SECTION_END_MARKER_DECL, dunno_what_it_is)])
+  AC_CACHE_VAL([fptools_cv_end_of_data], [AC_DEFINE_UNQUOTED(DATA_SECTION_END_MARKER, dunno_what_it_is)])
+fi
+fi
+AC_MSG_RESULT([$]fptools_cv_end_of_data)
+])
+
+
+
+dnl Based on AC_TRY_LINK - run iftrue if links cleanly with no warning
+
+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
+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
+else
+  AC_MSG_RESULT(no)
+  $5
+fi
+])
+
+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)
+fi
 ])
 
 
+# LocalWords:  fi