* configure.in (AC_EXEEXT): Work around in case it expands to

nothing, as in autoconf 2.50.
* configure: Rebuilt.


git-svn-id: https://gcc.gnu.org/svn/gcc/trunk@43103 138bc75d-0d04-0410-961f-82ee72b054a4

3 files changed, 69 insertions, 55 deletions

diff --git a/zlib/ChangeLog b/zlib/ChangeLog
index 57386a26f48..b1c1bbd53b8 100644
--- a/zlib/ChangeLog
+++ b/zlib/ChangeLog
@@ -1,3 +1,9 @@
+2001-06-09  Alexandre Oliva  <aoliva@redhat.com>, Stephen L Moshier  <moshier@mediaone.net>
+
+	* configure.in (AC_EXEEXT): Work around in case it expands to
+	nothing, as in autoconf 2.50.
+	* configure: Rebuilt.
+
 
 		ChangeLog file for zlib
 
@@ -215,7 +221,7 @@ Changes in 1.0.6 (19 Jan 1998)
 - use _fdopen instead of fdopen for MSC >= 6.0 (Thomas Fanslau)
 - added makelcc.bat for lcc-win32 (Tom St Denis)
 - in Makefile.dj2, use copy and del instead of install and rm (Frank Donahoe)
-- Avoid expanded $Id$. Use "rcs -kb" or "cvs admin -kb" to avoid Id expansion.
+- Avoid expanded $Id: ChangeLog,v 1.1 1999/05/04 19:30:26 tromey Exp $. Use "rcs -kb" or "cvs admin -kb" to avoid Id expansion.
 - check for unistd.h in configure (for off_t)
 - remove useless check parameter in inflate_blocks_free
 - avoid useless assignment of s->check to itself in inflate_blocks_new
diff --git a/zlib/configure b/zlib/configure
index 76c0af5f514..5985a736208 100755
--- a/zlib/configure
+++ b/zlib/configure
@@ -1133,13 +1133,17 @@ fi
 # automake happy, but we dont execute it, since we dont care about
 # the result.
 if false; then
+  # autoconf 2.50 runs AC_EXEEXT by default, and the macro expands
+  # to nothing, so nothing would remain between `then' and `fi' if it
+  # were not for the `:' below.
+  :
   echo $ac_n "checking for Cygwin environment""... $ac_c" 1>&6
-echo "configure:1138: checking for Cygwin environment" >&5
+echo "configure:1142: checking for Cygwin environment" >&5
 if eval "test \"`echo '$''{'ac_cv_cygwin'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1143 "configure"
+#line 1147 "configure"
 #include "confdefs.h"
 
 int main() {
@@ -1150,7 +1154,7 @@ int main() {
 return __CYGWIN__;
 ; return 0; }
 EOF
-if { (eval echo configure:1154: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
+if { (eval echo configure:1158: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
   rm -rf conftest*
   ac_cv_cygwin=yes
 else
@@ -1167,19 +1171,19 @@ echo "$ac_t""$ac_cv_cygwin" 1>&6
 CYGWIN=
 test "$ac_cv_cygwin" = yes && CYGWIN=yes
 echo $ac_n "checking for mingw32 environment""... $ac_c" 1>&6
-echo "configure:1171: checking for mingw32 environment" >&5
+echo "configure:1175: checking for mingw32 environment" >&5
 if eval "test \"`echo '$''{'ac_cv_mingw32'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1176 "configure"
+#line 1180 "configure"
 #include "confdefs.h"
 
 int main() {
 return __MINGW32__;
 ; return 0; }
 EOF
-if { (eval echo configure:1183: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
+if { (eval echo configure:1187: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
   rm -rf conftest*
   ac_cv_mingw32=yes
 else
@@ -1198,7 +1202,7 @@ test "$ac_cv_mingw32" = yes && MINGW32=yes
 
 
 echo $ac_n "checking for executable suffix""... $ac_c" 1>&6
-echo "configure:1202: checking for executable suffix" >&5
+echo "configure:1206: checking for executable suffix" >&5
 if eval "test \"`echo '$''{'ac_cv_exeext'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1208,7 +1212,7 @@ else
   rm -f conftest*
   echo 'int main () { return 0; }' > conftest.$ac_ext
   ac_cv_exeext=
-  if { (eval echo configure:1212: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; }; then
+  if { (eval echo configure:1216: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; }; then
     for file in conftest.*; do
       case $file in
       *.c | *.o | *.obj | *.ilk | *.pdb) ;;
@@ -1310,7 +1314,7 @@ ac_prog=ld
 if test "$GCC" = yes; then
   # Check if gcc -print-prog-name=ld gives a path.
   echo $ac_n "checking for ld used by GCC""... $ac_c" 1>&6
-echo "configure:1314: checking for ld used by GCC" >&5
+echo "configure:1318: checking for ld used by GCC" >&5
   case $host in
   *-*-mingw*)
     # gcc leaves a trailing carriage return which upsets mingw
@@ -1340,10 +1344,10 @@ echo "configure:1314: checking for ld used by GCC" >&5
   esac
 elif test "$with_gnu_ld" = yes; then
   echo $ac_n "checking for GNU ld""... $ac_c" 1>&6
-echo "configure:1344: checking for GNU ld" >&5
+echo "configure:1348: checking for GNU ld" >&5
 else
   echo $ac_n "checking for non-GNU ld""... $ac_c" 1>&6
-echo "configure:1347: checking for non-GNU ld" >&5
+echo "configure:1351: checking for non-GNU ld" >&5
 fi
 if eval "test \"`echo '$''{'lt_cv_path_LD'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
@@ -1378,7 +1382,7 @@ else
 fi
 test -z "$LD" && { echo "configure: error: no acceptable ld found in \$PATH" 1>&2; exit 1; }
 echo $ac_n "checking if the linker ($LD) is GNU ld""... $ac_c" 1>&6
-echo "configure:1382: checking if the linker ($LD) is GNU ld" >&5
+echo "configure:1386: checking if the linker ($LD) is GNU ld" >&5
 if eval "test \"`echo '$''{'lt_cv_prog_gnu_ld'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1395,7 +1399,7 @@ with_gnu_ld=$lt_cv_prog_gnu_ld
 
 
 echo $ac_n "checking for $LD option to reload object files""... $ac_c" 1>&6
-echo "configure:1399: checking for $LD option to reload object files" >&5
+echo "configure:1403: checking for $LD option to reload object files" >&5
 if eval "test \"`echo '$''{'lt_cv_ld_reload_flag'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1407,7 +1411,7 @@ reload_flag=$lt_cv_ld_reload_flag
 test -n "$reload_flag" && reload_flag=" $reload_flag"
 
 echo $ac_n "checking for BSD-compatible nm""... $ac_c" 1>&6
-echo "configure:1411: checking for BSD-compatible nm" >&5
+echo "configure:1415: checking for BSD-compatible nm" >&5
 if eval "test \"`echo '$''{'lt_cv_path_NM'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1445,7 +1449,7 @@ NM="$lt_cv_path_NM"
 echo "$ac_t""$NM" 1>&6
 
 echo $ac_n "checking whether ln -s works""... $ac_c" 1>&6
-echo "configure:1449: checking whether ln -s works" >&5
+echo "configure:1453: checking whether ln -s works" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_LN_S'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1466,7 +1470,7 @@ else
 fi
 
 echo $ac_n "checking how to recognise dependant libraries""... $ac_c" 1>&6
-echo "configure:1470: checking how to recognise dependant libraries" >&5
+echo "configure:1474: checking how to recognise dependant libraries" >&5
 if eval "test \"`echo '$''{'lt_cv_deplibs_check_method'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1630,13 +1634,13 @@ file_magic_cmd=$lt_cv_file_magic_cmd
 deplibs_check_method=$lt_cv_deplibs_check_method
 
 echo $ac_n "checking for object suffix""... $ac_c" 1>&6
-echo "configure:1634: checking for object suffix" >&5
+echo "configure:1638: checking for object suffix" >&5
 if eval "test \"`echo '$''{'ac_cv_objext'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   rm -f conftest*
 echo 'int i = 1;' > conftest.$ac_ext
-if { (eval echo configure:1640: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
+if { (eval echo configure:1644: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
   for ac_file in conftest.*; do
     case $ac_file in
     *.c) ;;
@@ -1666,7 +1670,7 @@ case $deplibs_check_method in
 file_magic*)
   if test "$file_magic_cmd" = '$MAGIC_CMD'; then
     echo $ac_n "checking for ${ac_tool_prefix}file""... $ac_c" 1>&6
-echo "configure:1670: checking for ${ac_tool_prefix}file" >&5
+echo "configure:1674: checking for ${ac_tool_prefix}file" >&5
 if eval "test \"`echo '$''{'lt_cv_path_MAGIC_CMD'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1728,7 +1732,7 @@ fi
 if test -z "$lt_cv_path_MAGIC_CMD"; then
   if test -n "$ac_tool_prefix"; then
     echo $ac_n "checking for file""... $ac_c" 1>&6
-echo "configure:1732: checking for file" >&5
+echo "configure:1736: checking for file" >&5
 if eval "test \"`echo '$''{'lt_cv_path_MAGIC_CMD'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1799,7 +1803,7 @@ esac
 # Extract the first word of "${ac_tool_prefix}ranlib", so it can be a program name with args.
 set dummy ${ac_tool_prefix}ranlib; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:1803: checking for $ac_word" >&5
+echo "configure:1807: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_RANLIB'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1831,7 +1835,7 @@ if test -n "$ac_tool_prefix"; then
   # Extract the first word of "ranlib", so it can be a program name with args.
 set dummy ranlib; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:1835: checking for $ac_word" >&5
+echo "configure:1839: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_RANLIB'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1866,7 +1870,7 @@ fi
 # Extract the first word of "${ac_tool_prefix}strip", so it can be a program name with args.
 set dummy ${ac_tool_prefix}strip; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:1870: checking for $ac_word" >&5
+echo "configure:1874: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_STRIP'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1898,7 +1902,7 @@ if test -n "$ac_tool_prefix"; then
   # Extract the first word of "strip", so it can be a program name with args.
 set dummy strip; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:1902: checking for $ac_word" >&5
+echo "configure:1906: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_STRIP'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1965,8 +1969,8 @@ test x"$pic_mode" = xno && libtool_flags="$libtool_flags --prefer-non-pic"
 case $host in
 *-*-irix6*)
   # Find out which ABI we are using.
-  echo '#line 1969 "configure"' > conftest.$ac_ext
-  if { (eval echo configure:1970: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
+  echo '#line 1973 "configure"' > conftest.$ac_ext
+  if { (eval echo configure:1974: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
     case `/usr/bin/file conftest.$ac_objext` in
     *32-bit*)
       LD="${LD-ld} -32"
@@ -1987,7 +1991,7 @@ case $host in
   SAVE_CFLAGS="$CFLAGS"
   CFLAGS="$CFLAGS -belf"
   echo $ac_n "checking whether the C compiler needs -belf""... $ac_c" 1>&6
-echo "configure:1991: checking whether the C compiler needs -belf" >&5
+echo "configure:1995: checking whether the C compiler needs -belf" >&5
 if eval "test \"`echo '$''{'lt_cv_cc_needs_belf'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -2000,14 +2004,14 @@ ac_link='${CC-cc} -o conftest${ac_exeext} $CFLAGS $CPPFLAGS $LDFLAGS conftest.$a
 cross_compiling=$ac_cv_prog_cc_cross
 
      cat > conftest.$ac_ext <<EOF
-#line 2004 "configure"
+#line 2008 "configure"
 #include "confdefs.h"
 
 int main() {
 
 ; return 0; }
 EOF
-if { (eval echo configure:2011: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2015: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   lt_cv_cc_needs_belf=yes
 else
@@ -2133,7 +2137,7 @@ fi
 # Find CPP now so that any conditional tests below won't do it and
 # thereby make the resulting definitions conditional.
 echo $ac_n "checking how to run the C preprocessor""... $ac_c" 1>&6
-echo "configure:2137: checking how to run the C preprocessor" >&5
+echo "configure:2141: checking how to run the C preprocessor" >&5
 # On Suns, sometimes $CPP names a directory.
 if test -n "$CPP" && test -d "$CPP"; then
   CPP=
@@ -2148,13 +2152,13 @@ else
   # On the NeXT, cc -E runs the code through the compiler's parser,
   # not just through cpp.
   cat > conftest.$ac_ext <<EOF
-#line 2152 "configure"
+#line 2156 "configure"
 #include "confdefs.h"
 #include <assert.h>
 Syntax Error
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:2158: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:2162: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   :
@@ -2165,13 +2169,13 @@ else
   rm -rf conftest*
   CPP="${CC-cc} -E -traditional-cpp"
   cat > conftest.$ac_ext <<EOF
-#line 2169 "configure"
+#line 2173 "configure"
 #include "confdefs.h"
 #include <assert.h>
 Syntax Error
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:2175: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:2179: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   :
@@ -2182,13 +2186,13 @@ else
   rm -rf conftest*
   CPP="${CC-cc} -nologo -E"
   cat > conftest.$ac_ext <<EOF
-#line 2186 "configure"
+#line 2190 "configure"
 #include "confdefs.h"
 #include <assert.h>
 Syntax Error
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:2192: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:2196: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   :
@@ -2236,17 +2240,17 @@ else
 do
 ac_safe=`echo "$ac_hdr" | sed 'y%./+-%__p_%'`
 echo $ac_n "checking for $ac_hdr""... $ac_c" 1>&6
-echo "configure:2240: checking for $ac_hdr" >&5
+echo "configure:2244: 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 2245 "configure"
+#line 2249 "configure"
 #include "confdefs.h"
 #include <$ac_hdr>
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:2250: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:2254: \"$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*
@@ -2275,12 +2279,12 @@ done
 for ac_func in getpagesize
 do
 echo $ac_n "checking for $ac_func""... $ac_c" 1>&6
-echo "configure:2279: checking for $ac_func" >&5
+echo "configure:2283: 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 2284 "configure"
+#line 2288 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char $ac_func(); below.  */
@@ -2303,7 +2307,7 @@ $ac_func();
 
 ; return 0; }
 EOF
-if { (eval echo configure:2307: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2311: \"$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
@@ -2328,7 +2332,7 @@ fi
 done
 
 echo $ac_n "checking for working mmap""... $ac_c" 1>&6
-echo "configure:2332: checking for working mmap" >&5
+echo "configure:2336: checking for working mmap" >&5
 if eval "test \"`echo '$''{'ac_cv_func_mmap_fixed_mapped'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -2336,7 +2340,7 @@ else
   ac_cv_func_mmap_fixed_mapped=no
 else
   cat > conftest.$ac_ext <<EOF
-#line 2340 "configure"
+#line 2344 "configure"
 #include "confdefs.h"
 
 /* Thanks to Mike Haertel and Jim Avera for this test.
@@ -2476,7 +2480,7 @@ main()
 }
 
 EOF
-if { (eval echo configure:2480: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext} && (./conftest; exit) 2>/dev/null
+if { (eval echo configure:2484: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext} && (./conftest; exit) 2>/dev/null
 then
   ac_cv_func_mmap_fixed_mapped=yes
 else
@@ -2501,12 +2505,12 @@ fi
    for ac_func in memcpy strerror
 do
 echo $ac_n "checking for $ac_func""... $ac_c" 1>&6
-echo "configure:2505: checking for $ac_func" >&5
+echo "configure:2509: 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 2510 "configure"
+#line 2514 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char $ac_func(); below.  */
@@ -2529,7 +2533,7 @@ $ac_func();
 
 ; return 0; }
 EOF
-if { (eval echo configure:2533: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2537: \"$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
@@ -2556,7 +2560,7 @@ done
 
    if test "$with_system_zlib" = yes; then
       echo $ac_n "checking for deflate in -lz""... $ac_c" 1>&6
-echo "configure:2560: checking for deflate in -lz" >&5
+echo "configure:2564: checking for deflate in -lz" >&5
 ac_lib_var=`echo z'_'deflate | sed 'y%./+-%__p_%'`
 if eval "test \"`echo '$''{'ac_cv_lib_$ac_lib_var'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
@@ -2564,7 +2568,7 @@ else
   ac_save_LIBS="$LIBS"
 LIBS="-lz  $LIBS"
 cat > conftest.$ac_ext <<EOF
-#line 2568 "configure"
+#line 2572 "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
@@ -2575,7 +2579,7 @@ int main() {
 deflate()
 ; return 0; }
 EOF
-if { (eval echo configure:2579: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2583: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_lib_$ac_lib_var=yes"
 else
@@ -2607,17 +2611,17 @@ for ac_hdr in unistd.h
 do
 ac_safe=`echo "$ac_hdr" | sed 'y%./+-%__p_%'`
 echo $ac_n "checking for $ac_hdr""... $ac_c" 1>&6
-echo "configure:2611: checking for $ac_hdr" >&5
+echo "configure:2615: 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 2616 "configure"
+#line 2620 "configure"
 #include "confdefs.h"
 #include <$ac_hdr>
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:2621: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:2625: \"$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*
diff --git a/zlib/configure.in b/zlib/configure.in
index 16544100174..d8cf0bc41dd 100644
--- a/zlib/configure.in
+++ b/zlib/configure.in
@@ -56,6 +56,10 @@ LIB_AC_PROG_CC
 # automake happy, but we dont execute it, since we dont care about
 # the result.
 if false; then
+  # autoconf 2.50 runs AC_EXEEXT by default, and the macro expands
+  # to nothing, so nothing would remain between `then' and `fi' if it
+  # were not for the `:' below.
+  :
   AC_EXEEXT
 fi
 AM_PROG_LIBTOOL