From: kvigor <kvigor@4a8a32a2-be11-0410-ad9d-d568d2c75423>
Date: Sat, 30 Sep 2000 21:37:32 +0000 (+0000)
Subject: Insist on bison: yacc isn't good enough
X-Git-Url: https://git.gag.com/?a=commitdiff_plain;h=8065aa73ff77e170a816e28dc7c4414a9b485d41;p=fw%2Fsdcc

Insist on bison: yacc isn't good enough


git-svn-id: https://sdcc.svn.sourceforge.net/svnroot/sdcc/trunk/sdcc@432 4a8a32a2-be11-0410-ad9d-d568d2c75423
---

diff --git a/configure b/configure
index 5383cd30..dec4f296 100755
--- a/configure
+++ b/configure
@@ -531,7 +531,7 @@ fi
 
 
 
-for ac_prog in gawk mawk nawk awk
+for ac_prog in mawk gawk nawk awk
 do
 # Extract the first word of "$ac_prog", so it can be a program name with args.
 set dummy $ac_prog; ac_word=$2
@@ -1164,45 +1164,10 @@ else
   echo "$ac_t""no" 1>&6
 fi
 
-for ac_prog in 'bison -y' byacc
-do
-# Extract the first word of "$ac_prog", so it can be a program name with args.
-set dummy $ac_prog; ac_word=$2
-echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:1173: checking for $ac_word" >&5
-if eval "test \"`echo '$''{'ac_cv_prog_YACC'+set}'`\" = set"; then
-  echo $ac_n "(cached) $ac_c" 1>&6
-else
-  if test -n "$YACC"; then
-  ac_cv_prog_YACC="$YACC" # Let the user override the test.
-else
-  IFS="${IFS= 	}"; ac_save_ifs="$IFS"; IFS=":"
-  ac_dummy="$PATH"
-  for ac_dir in $ac_dummy; do
-    test -z "$ac_dir" && ac_dir=.
-    if test -f $ac_dir/$ac_word; then
-      ac_cv_prog_YACC="$ac_prog"
-      break
-    fi
-  done
-  IFS="$ac_save_ifs"
-fi
-fi
-YACC="$ac_cv_prog_YACC"
-if test -n "$YACC"; then
-  echo "$ac_t""$YACC" 1>&6
-else
-  echo "$ac_t""no" 1>&6
-fi
-
-test -n "$YACC" && break
-done
-test -n "$YACC" || YACC="yacc"
-
 # Extract the first word of "flex", so it can be a program name with args.
 set dummy flex; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:1206: checking for $ac_word" >&5
+echo "configure:1171: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_LEX'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1236,7 +1201,7 @@ then
   *) ac_lib=l ;;
   esac
   echo $ac_n "checking for yywrap in -l$ac_lib""... $ac_c" 1>&6
-echo "configure:1240: checking for yywrap in -l$ac_lib" >&5
+echo "configure:1205: checking for yywrap in -l$ac_lib" >&5
 ac_lib_var=`echo $ac_lib'_'yywrap | sed 'y%./+-%__p_%'`
 if eval "test \"`echo '$''{'ac_cv_lib_$ac_lib_var'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
@@ -1244,7 +1209,7 @@ else
   ac_save_LIBS="$LIBS"
 LIBS="-l$ac_lib  $LIBS"
 cat > conftest.$ac_ext <<EOF
-#line 1248 "configure"
+#line 1213 "configure"
 #include "confdefs.h"
 /* Override any gcc2 internal prototype to avoid an error.  */
 /* We use char because int might match the return type of a gcc2
@@ -1255,7 +1220,7 @@ int main() {
 yywrap()
 ; return 0; }
 EOF
-if { (eval echo configure:1259: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:1224: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_lib_$ac_lib_var=yes"
 else
@@ -1277,10 +1242,40 @@ fi
 
 fi
 
+# Extract the first word of "bison", so it can be a program name with args.
+set dummy bison; ac_word=$2
+echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
+echo "configure:1249: checking for $ac_word" >&5
+if eval "test \"`echo '$''{'ac_cv_prog_YACC'+set}'`\" = set"; then
+  echo $ac_n "(cached) $ac_c" 1>&6
+else
+  if test -n "$YACC"; then
+  ac_cv_prog_YACC="$YACC" # Let the user override the test.
+else
+  IFS="${IFS= 	}"; ac_save_ifs="$IFS"; IFS=":"
+  ac_dummy="$PATH"
+  for ac_dir in $ac_dummy; do
+    test -z "$ac_dir" && ac_dir=.
+    if test -f $ac_dir/$ac_word; then
+      ac_cv_prog_YACC="bison -y"
+      break
+    fi
+  done
+  IFS="$ac_save_ifs"
+  test -z "$ac_cv_prog_YACC" && ac_cv_prog_YACC=":"
+fi
+fi
+YACC="$ac_cv_prog_YACC"
+if test -n "$YACC"; then
+  echo "$ac_t""$YACC" 1>&6
+else
+  echo "$ac_t""no" 1>&6
+fi
+
 # Extract the first word of "autoconf", so it can be a program name with args.
 set dummy autoconf; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:1284: checking for $ac_word" >&5
+echo "configure:1279: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_AUTOCONF'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1310,7 +1305,7 @@ fi
 # Extract the first word of "as", so it can be a program name with args.
 set dummy as; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:1314: checking for $ac_word" >&5
+echo "configure:1309: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_AS'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1340,7 +1335,7 @@ fi
 # Extract the first word of "cp", so it can be a program name with args.
 set dummy cp; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:1344: checking for $ac_word" >&5
+echo "configure:1339: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_CP'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1368,6 +1363,17 @@ else
 fi
 
 
+
+
+if test "$YACC" = ":"; then
+  { echo "configure: error: Cannot find required program bison." 1>&2; exit 1; }
+ fi
+
+if test "$LEX" = ":"; then
+  { echo "configure: error: Cannot find required program lex." 1>&2; exit 1; }
+ fi
+
+
 ac_ext=c
 # CFLAGS is not in ac_cpp because -g, -O, etc. are not valid cpp options.
 ac_cpp='$CPP $CPPFLAGS'
@@ -1379,12 +1385,12 @@ cross_compiling=$ac_cv_prog_cc_cross
 # Checking for header files.
 # ===========================================================================
 echo $ac_n "checking for ANSI C header files""... $ac_c" 1>&6
-echo "configure:1383: checking for ANSI C header files" >&5
+echo "configure:1389: checking for ANSI C header files" >&5
 if eval "test \"`echo '$''{'ac_cv_header_stdc'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1388 "configure"
+#line 1394 "configure"
 #include "confdefs.h"
 #include <stdlib.h>
 #include <stdarg.h>
@@ -1392,7 +1398,7 @@ else
 #include <float.h>
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:1396: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:1402: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   rm -rf conftest*
@@ -1409,7 +1415,7 @@ rm -f conftest*
 if test $ac_cv_header_stdc = yes; then
   # SunOS 4.x string.h does not declare mem*, contrary to ANSI.
 cat > conftest.$ac_ext <<EOF
-#line 1413 "configure"
+#line 1419 "configure"
 #include "confdefs.h"
 #include <string.h>
 EOF
@@ -1427,7 +1433,7 @@ fi
 if test $ac_cv_header_stdc = yes; then
   # ISC 2.0.2 stdlib.h does not declare free, contrary to ANSI.
 cat > conftest.$ac_ext <<EOF
-#line 1431 "configure"
+#line 1437 "configure"
 #include "confdefs.h"
 #include <stdlib.h>
 EOF
@@ -1448,7 +1454,7 @@ if test "$cross_compiling" = yes; then
   :
 else
   cat > conftest.$ac_ext <<EOF
-#line 1452 "configure"
+#line 1458 "configure"
 #include "confdefs.h"
 #include <ctype.h>
 #define ISLOWER(c) ('a' <= (c) && (c) <= 'z')
@@ -1459,7 +1465,7 @@ if (XOR (islower (i), ISLOWER (i)) || toupper (i) != TOUPPER (i)) exit(2);
 exit (0); }
 
 EOF
-if { (eval echo configure:1463: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext} && (./conftest; exit) 2>/dev/null
+if { (eval echo configure:1469: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext} && (./conftest; exit) 2>/dev/null
 then
   :
 else
@@ -1486,17 +1492,17 @@ for ac_hdr in getopt.h
 do
 ac_safe=`echo "$ac_hdr" | sed 'y%./+-%__p_%'`
 echo $ac_n "checking for $ac_hdr""... $ac_c" 1>&6
-echo "configure:1490: checking for $ac_hdr" >&5
+echo "configure:1496: checking for $ac_hdr" >&5
 if eval "test \"`echo '$''{'ac_cv_header_$ac_safe'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1495 "configure"
+#line 1501 "configure"
 #include "confdefs.h"
 #include <$ac_hdr>
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:1500: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:1506: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   rm -rf conftest*
@@ -1526,17 +1532,17 @@ for ac_hdr in unistd.h
 do
 ac_safe=`echo "$ac_hdr" | sed 'y%./+-%__p_%'`
 echo $ac_n "checking for $ac_hdr""... $ac_c" 1>&6
-echo "configure:1530: checking for $ac_hdr" >&5
+echo "configure:1536: checking for $ac_hdr" >&5
 if eval "test \"`echo '$''{'ac_cv_header_$ac_safe'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1535 "configure"
+#line 1541 "configure"
 #include "confdefs.h"
 #include <$ac_hdr>
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:1540: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:1546: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   rm -rf conftest*
@@ -1566,17 +1572,17 @@ for ac_hdr in endian.h
 do
 ac_safe=`echo "$ac_hdr" | sed 'y%./+-%__p_%'`
 echo $ac_n "checking for $ac_hdr""... $ac_c" 1>&6
-echo "configure:1570: checking for $ac_hdr" >&5
+echo "configure:1576: checking for $ac_hdr" >&5
 if eval "test \"`echo '$''{'ac_cv_header_$ac_safe'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1575 "configure"
+#line 1581 "configure"
 #include "confdefs.h"
 #include <$ac_hdr>
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:1580: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:1586: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   rm -rf conftest*
@@ -1606,17 +1612,17 @@ for ac_hdr in sys/isa_defs.h
 do
 ac_safe=`echo "$ac_hdr" | sed 'y%./+-%__p_%'`
 echo $ac_n "checking for $ac_hdr""... $ac_c" 1>&6
-echo "configure:1610: checking for $ac_hdr" >&5
+echo "configure:1616: checking for $ac_hdr" >&5
 if eval "test \"`echo '$''{'ac_cv_header_$ac_safe'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1615 "configure"
+#line 1621 "configure"
 #include "confdefs.h"
 #include <$ac_hdr>
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:1620: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:1626: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   rm -rf conftest*
@@ -1646,17 +1652,17 @@ for ac_hdr in sys/socket.h
 do
 ac_safe=`echo "$ac_hdr" | sed 'y%./+-%__p_%'`
 echo $ac_n "checking for $ac_hdr""... $ac_c" 1>&6
-echo "configure:1650: checking for $ac_hdr" >&5
+echo "configure:1656: checking for $ac_hdr" >&5
 if eval "test \"`echo '$''{'ac_cv_header_$ac_safe'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1655 "configure"
+#line 1661 "configure"
 #include "confdefs.h"
 #include <$ac_hdr>
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:1660: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:1666: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   rm -rf conftest*
@@ -1687,12 +1693,12 @@ for ac_hdr in dirent.h sys/ndir.h sys/dir.h ndir.h
 do
 ac_safe=`echo "$ac_hdr" | sed 'y%./+-%__p_%'`
 echo $ac_n "checking for $ac_hdr that defines DIR""... $ac_c" 1>&6
-echo "configure:1691: checking for $ac_hdr that defines DIR" >&5
+echo "configure:1697: checking for $ac_hdr that defines DIR" >&5
 if eval "test \"`echo '$''{'ac_cv_header_dirent_$ac_safe'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1696 "configure"
+#line 1702 "configure"
 #include "confdefs.h"
 #include <sys/types.h>
 #include <$ac_hdr>
@@ -1700,7 +1706,7 @@ int main() {
 DIR *dirp = 0;
 ; return 0; }
 EOF
-if { (eval echo configure:1704: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
+if { (eval echo configure:1710: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
   rm -rf conftest*
   eval "ac_cv_header_dirent_$ac_safe=yes"
 else
@@ -1725,7 +1731,7 @@ done
 # Two versions of opendir et al. are in -ldir and -lx on SCO Xenix.
 if test $ac_header_dirent = dirent.h; then
 echo $ac_n "checking for opendir in -ldir""... $ac_c" 1>&6
-echo "configure:1729: checking for opendir in -ldir" >&5
+echo "configure:1735: checking for opendir in -ldir" >&5
 ac_lib_var=`echo dir'_'opendir | sed 'y%./+-%__p_%'`
 if eval "test \"`echo '$''{'ac_cv_lib_$ac_lib_var'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
@@ -1733,7 +1739,7 @@ else
   ac_save_LIBS="$LIBS"
 LIBS="-ldir  $LIBS"
 cat > conftest.$ac_ext <<EOF
-#line 1737 "configure"
+#line 1743 "configure"
 #include "confdefs.h"
 /* Override any gcc2 internal prototype to avoid an error.  */
 /* We use char because int might match the return type of a gcc2
@@ -1744,7 +1750,7 @@ int main() {
 opendir()
 ; return 0; }
 EOF
-if { (eval echo configure:1748: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:1754: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_lib_$ac_lib_var=yes"
 else
@@ -1766,7 +1772,7 @@ fi
 
 else
 echo $ac_n "checking for opendir in -lx""... $ac_c" 1>&6
-echo "configure:1770: checking for opendir in -lx" >&5
+echo "configure:1776: checking for opendir in -lx" >&5
 ac_lib_var=`echo x'_'opendir | sed 'y%./+-%__p_%'`
 if eval "test \"`echo '$''{'ac_cv_lib_$ac_lib_var'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
@@ -1774,7 +1780,7 @@ else
   ac_save_LIBS="$LIBS"
 LIBS="-lx  $LIBS"
 cat > conftest.$ac_ext <<EOF
-#line 1778 "configure"
+#line 1784 "configure"
 #include "confdefs.h"
 /* Override any gcc2 internal prototype to avoid an error.  */
 /* We use char because int might match the return type of a gcc2
@@ -1785,7 +1791,7 @@ int main() {
 opendir()
 ; return 0; }
 EOF
-if { (eval echo configure:1789: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:1795: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_lib_$ac_lib_var=yes"
 else
@@ -1811,13 +1817,13 @@ fi
 # This must be after CPP
 
 echo $ac_n "checking which header file defines FD_ macros""... $ac_c" 1>&6
-echo "configure:1815: checking which header file defines FD_ macros" >&5
+echo "configure:1821: checking which header file defines FD_ macros" >&5
 if eval "test \"`echo '$''{'s51_cv_fd'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   sdcc_cv_fd="unknown"
 cat > conftest.$ac_ext <<EOF
-#line 1821 "configure"
+#line 1827 "configure"
 #include "confdefs.h"
 
 #include <sys/time.h>
@@ -1833,7 +1839,7 @@ fi
 rm -f conftest*
 
 cat > conftest.$ac_ext <<EOF
-#line 1837 "configure"
+#line 1843 "configure"
 #include "confdefs.h"
 
 #include <sys/types.h>
@@ -1849,7 +1855,7 @@ fi
 rm -f conftest*
 
 cat > conftest.$ac_ext <<EOF
-#line 1853 "configure"
+#line 1859 "configure"
 #include "confdefs.h"
 
 #include <sys/select.h>
@@ -1929,12 +1935,12 @@ EOF
 for ac_func in strlen strcpy strcat strstr strcmp strerror strtok strdup
 do
 echo $ac_n "checking for $ac_func""... $ac_c" 1>&6
-echo "configure:1933: checking for $ac_func" >&5
+echo "configure:1939: checking for $ac_func" >&5
 if eval "test \"`echo '$''{'ac_cv_func_$ac_func'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1938 "configure"
+#line 1944 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char $ac_func(); below.  */
@@ -1957,7 +1963,7 @@ $ac_func();
 
 ; return 0; }
 EOF
-if { (eval echo configure:1961: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:1967: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_func_$ac_func=yes"
 else
@@ -1984,12 +1990,12 @@ done
 for ac_func in strchr memcpy
 do
 echo $ac_n "checking for $ac_func""... $ac_c" 1>&6
-echo "configure:1988: checking for $ac_func" >&5
+echo "configure:1994: checking for $ac_func" >&5
 if eval "test \"`echo '$''{'ac_cv_func_$ac_func'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1993 "configure"
+#line 1999 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char $ac_func(); below.  */
@@ -2012,7 +2018,7 @@ $ac_func();
 
 ; return 0; }
 EOF
-if { (eval echo configure:2016: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2022: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_func_$ac_func=yes"
 else
@@ -2039,12 +2045,12 @@ done
 for ac_func in fgets
 do
 echo $ac_n "checking for $ac_func""... $ac_c" 1>&6
-echo "configure:2043: checking for $ac_func" >&5
+echo "configure:2049: checking for $ac_func" >&5
 if eval "test \"`echo '$''{'ac_cv_func_$ac_func'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 2048 "configure"
+#line 2054 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char $ac_func(); below.  */
@@ -2067,7 +2073,7 @@ $ac_func();
 
 ; return 0; }
 EOF
-if { (eval echo configure:2071: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2077: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_func_$ac_func=yes"
 else
@@ -2094,12 +2100,12 @@ done
 for ac_func in yylex
 do
 echo $ac_n "checking for $ac_func""... $ac_c" 1>&6
-echo "configure:2098: checking for $ac_func" >&5
+echo "configure:2104: checking for $ac_func" >&5
 if eval "test \"`echo '$''{'ac_cv_func_$ac_func'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 2103 "configure"
+#line 2109 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char $ac_func(); below.  */
@@ -2122,7 +2128,7 @@ $ac_func();
 
 ; return 0; }
 EOF
-if { (eval echo configure:2126: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2132: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_func_$ac_func=yes"
 else
@@ -2150,14 +2156,14 @@ done
 # check if -lsocket && -lxnet is required to compile socket stuff
 
 echo $ac_n "checking for library containing socket""... $ac_c" 1>&6
-echo "configure:2154: checking for library containing socket" >&5
+echo "configure:2160: checking for library containing socket" >&5
 if eval "test \"`echo '$''{'ac_cv_search_socket'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   ac_func_search_save_LIBS="$LIBS"
 ac_cv_search_socket="no"
 cat > conftest.$ac_ext <<EOF
-#line 2161 "configure"
+#line 2167 "configure"
 #include "confdefs.h"
 /* Override any gcc2 internal prototype to avoid an error.  */
 /* We use char because int might match the return type of a gcc2
@@ -2168,7 +2174,7 @@ int main() {
 socket()
 ; return 0; }
 EOF
-if { (eval echo configure:2172: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2178: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   ac_cv_search_socket="none required"
 else
@@ -2179,7 +2185,7 @@ rm -f conftest*
 test "$ac_cv_search_socket" = "no" && for i in socket; do
 LIBS="-l$i  $ac_func_search_save_LIBS"
 cat > conftest.$ac_ext <<EOF
-#line 2183 "configure"
+#line 2189 "configure"
 #include "confdefs.h"
 /* Override any gcc2 internal prototype to avoid an error.  */
 /* We use char because int might match the return type of a gcc2
@@ -2190,7 +2196,7 @@ int main() {
 socket()
 ; return 0; }
 EOF
-if { (eval echo configure:2194: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2200: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   ac_cv_search_socket="-l$i"
 break
@@ -2212,14 +2218,14 @@ else :
 fi
 
 echo $ac_n "checking for library containing inet_addr""... $ac_c" 1>&6
-echo "configure:2216: checking for library containing inet_addr" >&5
+echo "configure:2222: checking for library containing inet_addr" >&5
 if eval "test \"`echo '$''{'ac_cv_search_inet_addr'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   ac_func_search_save_LIBS="$LIBS"
 ac_cv_search_inet_addr="no"
 cat > conftest.$ac_ext <<EOF
-#line 2223 "configure"
+#line 2229 "configure"
 #include "confdefs.h"
 /* Override any gcc2 internal prototype to avoid an error.  */
 /* We use char because int might match the return type of a gcc2
@@ -2230,7 +2236,7 @@ int main() {
 inet_addr()
 ; return 0; }
 EOF
-if { (eval echo configure:2234: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2240: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   ac_cv_search_inet_addr="none required"
 else
@@ -2241,7 +2247,7 @@ rm -f conftest*
 test "$ac_cv_search_inet_addr" = "no" && for i in nsl xnet; do
 LIBS="-l$i  $ac_func_search_save_LIBS"
 cat > conftest.$ac_ext <<EOF
-#line 2245 "configure"
+#line 2251 "configure"
 #include "confdefs.h"
 /* Override any gcc2 internal prototype to avoid an error.  */
 /* We use char because int might match the return type of a gcc2
@@ -2252,7 +2258,7 @@ int main() {
 inet_addr()
 ; return 0; }
 EOF
-if { (eval echo configure:2256: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2262: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   ac_cv_search_inet_addr="-l$i"
 break
@@ -2286,7 +2292,7 @@ fi
 # Checking characteristics of compilers and other programs
 # --------------------------------------------------------
 echo $ac_n "checking whether preprocessor accepts -MM or -M""... $ac_c" 1>&6
-echo "configure:2290: checking whether preprocessor accepts -MM or -M" >&5
+echo "configure:2296: checking whether preprocessor accepts -MM or -M" >&5
 if eval "test \"`echo '$''{'sdcc_cv_MM'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -2308,7 +2314,7 @@ M_OR_MM=$sdcc_cv_MM
 # This is the first time when CFLAGS are set/modified!!
 
 echo $ac_n "checking whether $CC accepts -ggdb""... $ac_c" 1>&6
-echo "configure:2312: checking whether $CC accepts -ggdb" >&5
+echo "configure:2318: checking whether $CC accepts -ggdb" >&5
 if eval "test \"`echo '$''{'sdcc_cv_CCggdb'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -2333,7 +2339,7 @@ fi
 
 
 echo $ac_n "checking whether $CC accepts -pipe""... $ac_c" 1>&6
-echo "configure:2337: checking whether $CC accepts -pipe" >&5
+echo "configure:2343: checking whether $CC accepts -pipe" >&5
 if eval "test \"`echo '$''{'sdcc_cv_CCpipe'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -2360,12 +2366,12 @@ fi
 # Checks for typedefs, structures, and compiler characteristics.
 # ===========================================================================
 echo $ac_n "checking return type of signal handlers""... $ac_c" 1>&6
-echo "configure:2364: checking return type of signal handlers" >&5
+echo "configure:2370: checking return type of signal handlers" >&5
 if eval "test \"`echo '$''{'ac_cv_type_signal'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 2369 "configure"
+#line 2375 "configure"
 #include "confdefs.h"
 #include <sys/types.h>
 #include <signal.h>
@@ -2382,7 +2388,7 @@ int main() {
 int i;
 ; return 0; }
 EOF
-if { (eval echo configure:2386: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
+if { (eval echo configure:2392: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
   rm -rf conftest*
   ac_cv_type_signal=void
 else
@@ -2461,7 +2467,7 @@ EOF
 
 # mlh: dont compile libgc if it's available locally
 echo $ac_n "checking for GC_malloc in -lgc""... $ac_c" 1>&6
-echo "configure:2465: checking for GC_malloc in -lgc" >&5
+echo "configure:2471: checking for GC_malloc in -lgc" >&5
 ac_lib_var=`echo gc'_'GC_malloc | sed 'y%./+-%__p_%'`
 if eval "test \"`echo '$''{'ac_cv_lib_$ac_lib_var'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
@@ -2469,7 +2475,7 @@ else
   ac_save_LIBS="$LIBS"
 LIBS="-lgc  $LIBS"
 cat > conftest.$ac_ext <<EOF
-#line 2473 "configure"
+#line 2479 "configure"
 #include "confdefs.h"
 /* Override any gcc2 internal prototype to avoid an error.  */
 /* We use char because int might match the return type of a gcc2
@@ -2480,7 +2486,7 @@ int main() {
 GC_malloc()
 ; return 0; }
 EOF
-if { (eval echo configure:2484: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2490: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_lib_$ac_lib_var=yes"
 else
@@ -2737,9 +2743,9 @@ s%@INSTALL_PROGRAM@%$INSTALL_PROGRAM%g
 s%@INSTALL_SCRIPT@%$INSTALL_SCRIPT%g
 s%@INSTALL_DATA@%$INSTALL_DATA%g
 s%@RANLIB@%$RANLIB%g
-s%@YACC@%$YACC%g
 s%@LEX@%$LEX%g
 s%@LEXLIB@%$LEXLIB%g
+s%@YACC@%$YACC%g
 s%@AUTOCONF@%$AUTOCONF%g
 s%@AS@%$AS%g
 s%@CP@%$CP%g
diff --git a/configure.in b/configure.in
index 1cf8153a..e954c4f8 100755
--- a/configure.in
+++ b/configure.in
@@ -37,12 +37,21 @@ AC_PROG_CXX
 AC_PROG_CPP
 AC_PROG_INSTALL
 AC_PROG_RANLIB
-AC_PROG_YACC(bison, :)
 AC_PROG_LEX(flex, :)
+AC_CHECK_PROG(YACC, bison, bison -y, :)
 AC_CHECK_PROG(AUTOCONF, autoconf, autoconf, :)
 AC_CHECK_PROG(AS, as, as, :)
 AC_CHECK_PROG(CP, cp, cp, :)
 
+AC_DEFUN(SDCC_REQUIRE_PROG, 
+[if test "$1" = ":"; then
+  AC_MSG_ERROR([Cannot find required program $2.])
+ fi
+])
+
+SDCC_REQUIRE_PROG($YACC, bison)
+SDCC_REQUIRE_PROG($LEX, lex)
+
 AC_LANG_C
 
 # Checking for header files.