From 2666a6d0b934b19d4a691b93a64c7d3208acad43 Mon Sep 17 00:00:00 2001
From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Tue, 18 Dec 2012 16:22:13 -0500
Subject: [PATCH] Ignore libedit/libreadline while probing for standard
 functions.

Some versions of libedit expose bogus definitions of setproctitle(),
optreset, and perhaps other symbols that we don't want configure to pick up
on.  There was a previous report of similar problems with strlcpy(), which
we addressed in commit 59cf88da91bc88978b05275ebd94ac2d980c4047, but the
problem has evidently grown in scope since then.  In hopes of not having to
deal with it again in future, rearrange configure's tests for supplied
functions so that we ignore libedit/libreadline except when probing
specifically for functions we expect them to provide.

Per report from Christoph Berg, though this is slightly more aggressive
than his proposed patch.
---
 configure    | 737 ++++++++++++++++++++++++++-------------------------
 configure.in |  31 +--
 2 files changed, 385 insertions(+), 383 deletions(-)

diff --git a/configure b/configure
index 85b4b952cbf..c6ffe6cd15f 100755
--- a/configure
+++ b/configure
@@ -19343,6 +19343,13 @@ fi
 
 
 
+# Some versions of libedit contain strlcpy(), setproctitle(), and other
+# symbols that that library has no business exposing to the world.  Pending
+# acquisition of a clue by those developers, ignore libedit (including its
+# possible alias of libreadline) while checking for everything else.
+LIBS_including_readline="$LIBS"
+LIBS=`echo "$LIBS" | sed -e 's/-ledit//g' -e 's/-lreadline//g'`
+
 
 
 
@@ -20916,11 +20923,6 @@ done
 
 fi
 
-# Some versions of libedit contain strlcpy(); so disregard that library while
-# checking for these standard libc functions.
-pgac_save_LIBS="$LIBS"
-LIBS=`echo "$LIBS" | sed -e 's/-ledit//g' -e 's/-lreadline//g'`
-
 
 
 
@@ -21173,9 +21175,6 @@ done
 		;;
 esac
 
-
-LIBS="$pgac_save_LIBS"
-
 # System's version of getaddrinfo(), if any, may be used only if we found
 # a definition for struct addrinfo; see notes in src/include/getaddrinfo.h.
 # (Note: the AC_REPLACE_FUNCS probe fails on Windows, where the available
@@ -21718,10 +21717,9 @@ else
 
 fi
 
-if test "$with_readline" = yes; then
-  { $as_echo "$as_me:$LINENO: checking for rl_completion_append_character" >&5
-$as_echo_n "checking for rl_completion_append_character... " >&6; }
-if test "${pgac_cv_var_rl_completion_append_character+set}" = set; then
+{ $as_echo "$as_me:$LINENO: checking for sigsetjmp" >&5
+$as_echo_n "checking for sigsetjmp... " >&6; }
+if test "${pgac_cv_func_sigsetjmp+set}" = set; then
   $as_echo_n "(cached) " >&6
 else
   cat >conftest.$ac_ext <<_ACEOF
@@ -21730,17 +21728,11 @@ _ACEOF
 cat confdefs.h >>conftest.$ac_ext
 cat >>conftest.$ac_ext <<_ACEOF
 /* end confdefs.h.  */
-#include <stdio.h>
-#ifdef HAVE_READLINE_READLINE_H
-# include <readline/readline.h>
-#elif defined(HAVE_READLINE_H)
-# include <readline.h>
-#endif
-
+#include <setjmp.h>
 int
 main ()
 {
-rl_completion_append_character = 'x';
+sigjmp_buf x; sigsetjmp(x, 1);
   ;
   return 0;
 }
@@ -21766,35 +21758,31 @@ $as_echo "$ac_try_echo") >&5
 	 test "$cross_compiling" = yes ||
 	 $as_test_x conftest$ac_exeext
        }; then
-  pgac_cv_var_rl_completion_append_character=yes
+  pgac_cv_func_sigsetjmp=yes
 else
   $as_echo "$as_me: failed program was:" >&5
 sed 's/^/| /' conftest.$ac_ext >&5
 
-	pgac_cv_var_rl_completion_append_character=no
+	pgac_cv_func_sigsetjmp=no
 fi
 
 rm -rf conftest.dSYM
 rm -f core conftest.err conftest.$ac_objext conftest_ipa8_conftest.oo \
       conftest$ac_exeext conftest.$ac_ext
 fi
-{ $as_echo "$as_me:$LINENO: result: $pgac_cv_var_rl_completion_append_character" >&5
-$as_echo "$pgac_cv_var_rl_completion_append_character" >&6; }
-if test x"$pgac_cv_var_rl_completion_append_character" = x"yes"; then
+{ $as_echo "$as_me:$LINENO: result: $pgac_cv_func_sigsetjmp" >&5
+$as_echo "$pgac_cv_func_sigsetjmp" >&6; }
+if test x"$pgac_cv_func_sigsetjmp" = x"yes"; then
 
 cat >>confdefs.h <<\_ACEOF
-#define HAVE_RL_COMPLETION_APPEND_CHARACTER 1
+#define HAVE_SIGSETJMP 1
 _ACEOF
 
 fi
 
-
-for ac_func in rl_completion_matches rl_filename_completion_function
-do
-as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh`
-{ $as_echo "$as_me:$LINENO: checking for $ac_func" >&5
-$as_echo_n "checking for $ac_func... " >&6; }
-if { as_var=$as_ac_var; eval "test \"\${$as_var+set}\" = set"; }; then
+{ $as_echo "$as_me:$LINENO: checking whether sys_siglist is declared" >&5
+$as_echo_n "checking whether sys_siglist is declared... " >&6; }
+if test "${ac_cv_have_decl_sys_siglist+set}" = set; then
   $as_echo_n "(cached) " >&6
 else
   cat >conftest.$ac_ext <<_ACEOF
@@ -21803,54 +21791,33 @@ _ACEOF
 cat confdefs.h >>conftest.$ac_ext
 cat >>conftest.$ac_ext <<_ACEOF
 /* end confdefs.h.  */
-/* Define $ac_func to an innocuous variant, in case <limits.h> declares $ac_func.
-   For example, HP-UX 11i <limits.h> declares gettimeofday.  */
-#define $ac_func innocuous_$ac_func
-
-/* System header to define __stub macros and hopefully few prototypes,
-    which can conflict with char $ac_func (); below.
-    Prefer <limits.h> to <assert.h> if __STDC__ is defined, since
-    <limits.h> exists even on freestanding compilers.  */
-
-#ifdef __STDC__
-# include <limits.h>
-#else
-# include <assert.h>
+#include <signal.h>
+/* NetBSD declares sys_siglist in unistd.h.  */
+#ifdef HAVE_UNISTD_H
+# include <unistd.h>
 #endif
 
-#undef $ac_func
-
-/* Override any GCC internal prototype to avoid an error.
-   Use char because int might match the return type of a GCC
-   builtin and then its argument prototype would still apply.  */
-#ifdef __cplusplus
-extern "C"
-#endif
-char $ac_func ();
-/* The GNU C library defines this for functions which it implements
-    to always fail with ENOSYS.  Some functions are actually named
-    something starting with __ and the normal name is an alias.  */
-#if defined __stub_$ac_func || defined __stub___$ac_func
-choke me
-#endif
 
 int
 main ()
 {
-return $ac_func ();
+#ifndef sys_siglist
+  (void) sys_siglist;
+#endif
+
   ;
   return 0;
 }
 _ACEOF
-rm -f conftest.$ac_objext conftest$ac_exeext
-if { (ac_try="$ac_link"
+rm -f conftest.$ac_objext
+if { (ac_try="$ac_compile"
 case "(($ac_try" in
   *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
   *) ac_try_echo=$ac_try;;
 esac
 eval ac_try_echo="\"\$as_me:$LINENO: $ac_try_echo\""
 $as_echo "$ac_try_echo") >&5
-  (eval "$ac_link") 2>conftest.er1
+  (eval "$ac_compile") 2>conftest.er1
   ac_status=$?
   grep -v '^ *+' conftest.er1 >conftest.err
   rm -f conftest.er1
@@ -21859,44 +21826,40 @@ $as_echo "$ac_try_echo") >&5
   (exit $ac_status); } && {
 	 test -z "$ac_c_werror_flag" ||
 	 test ! -s conftest.err
-       } && test -s conftest$ac_exeext && {
-	 test "$cross_compiling" = yes ||
-	 $as_test_x conftest$ac_exeext
-       }; then
-  eval "$as_ac_var=yes"
+       } && test -s conftest.$ac_objext; then
+  ac_cv_have_decl_sys_siglist=yes
 else
   $as_echo "$as_me: failed program was:" >&5
 sed 's/^/| /' conftest.$ac_ext >&5
 
-	eval "$as_ac_var=no"
+	ac_cv_have_decl_sys_siglist=no
 fi
 
-rm -rf conftest.dSYM
-rm -f core conftest.err conftest.$ac_objext conftest_ipa8_conftest.oo \
-      conftest$ac_exeext conftest.$ac_ext
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
 fi
-ac_res=`eval 'as_val=${'$as_ac_var'}
-		 $as_echo "$as_val"'`
-	       { $as_echo "$as_me:$LINENO: result: $ac_res" >&5
-$as_echo "$ac_res" >&6; }
-as_val=`eval 'as_val=${'$as_ac_var'}
-		 $as_echo "$as_val"'`
-   if test "x$as_val" = x""yes; then
+{ $as_echo "$as_me:$LINENO: result: $ac_cv_have_decl_sys_siglist" >&5
+$as_echo "$ac_cv_have_decl_sys_siglist" >&6; }
+if test "x$ac_cv_have_decl_sys_siglist" = x""yes; then
+
+cat >>confdefs.h <<_ACEOF
+#define HAVE_DECL_SYS_SIGLIST 1
+_ACEOF
+
+
+else
   cat >>confdefs.h <<_ACEOF
-#define `$as_echo "HAVE_$ac_func" | $as_tr_cpp` 1
+#define HAVE_DECL_SYS_SIGLIST 0
 _ACEOF
 
+
 fi
-done
 
 
 
-for ac_func in append_history history_truncate_file
-do
-as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh`
-{ $as_echo "$as_me:$LINENO: checking for $ac_func" >&5
-$as_echo_n "checking for $ac_func... " >&6; }
-if { as_var=$as_ac_var; eval "test \"\${$as_var+set}\" = set"; }; then
+
+{ $as_echo "$as_me:$LINENO: checking for syslog" >&5
+$as_echo_n "checking for syslog... " >&6; }
+if test "${ac_cv_func_syslog+set}" = set; then
   $as_echo_n "(cached) " >&6
 else
   cat >conftest.$ac_ext <<_ACEOF
@@ -21905,12 +21868,12 @@ _ACEOF
 cat confdefs.h >>conftest.$ac_ext
 cat >>conftest.$ac_ext <<_ACEOF
 /* end confdefs.h.  */
-/* Define $ac_func to an innocuous variant, in case <limits.h> declares $ac_func.
+/* Define syslog to an innocuous variant, in case <limits.h> declares syslog.
    For example, HP-UX 11i <limits.h> declares gettimeofday.  */
-#define $ac_func innocuous_$ac_func
+#define syslog innocuous_syslog
 
 /* System header to define __stub macros and hopefully few prototypes,
-    which can conflict with char $ac_func (); below.
+    which can conflict with char syslog (); below.
     Prefer <limits.h> to <assert.h> if __STDC__ is defined, since
     <limits.h> exists even on freestanding compilers.  */
 
@@ -21920,7 +21883,7 @@ cat >>conftest.$ac_ext <<_ACEOF
 # include <assert.h>
 #endif
 
-#undef $ac_func
+#undef syslog
 
 /* Override any GCC internal prototype to avoid an error.
    Use char because int might match the return type of a GCC
@@ -21928,18 +21891,18 @@ cat >>conftest.$ac_ext <<_ACEOF
 #ifdef __cplusplus
 extern "C"
 #endif
-char $ac_func ();
+char syslog ();
 /* The GNU C library defines this for functions which it implements
     to always fail with ENOSYS.  Some functions are actually named
     something starting with __ and the normal name is an alias.  */
-#if defined __stub_$ac_func || defined __stub___$ac_func
+#if defined __stub_syslog || defined __stub___syslog
 choke me
 #endif
 
 int
 main ()
 {
-return $ac_func ();
+return syslog ();
   ;
   return 0;
 }
@@ -21965,64 +21928,51 @@ $as_echo "$ac_try_echo") >&5
 	 test "$cross_compiling" = yes ||
 	 $as_test_x conftest$ac_exeext
        }; then
-  eval "$as_ac_var=yes"
+  ac_cv_func_syslog=yes
 else
   $as_echo "$as_me: failed program was:" >&5
 sed 's/^/| /' conftest.$ac_ext >&5
 
-	eval "$as_ac_var=no"
+	ac_cv_func_syslog=no
 fi
 
 rm -rf conftest.dSYM
 rm -f core conftest.err conftest.$ac_objext conftest_ipa8_conftest.oo \
       conftest$ac_exeext conftest.$ac_ext
 fi
-ac_res=`eval 'as_val=${'$as_ac_var'}
-		 $as_echo "$as_val"'`
-	       { $as_echo "$as_me:$LINENO: result: $ac_res" >&5
-$as_echo "$ac_res" >&6; }
-as_val=`eval 'as_val=${'$as_ac_var'}
-		 $as_echo "$as_val"'`
-   if test "x$as_val" = x""yes; then
-  cat >>confdefs.h <<_ACEOF
-#define `$as_echo "HAVE_$ac_func" | $as_tr_cpp` 1
-_ACEOF
-
-fi
-done
-
-fi
-
-
-{ $as_echo "$as_me:$LINENO: checking for sigsetjmp" >&5
-$as_echo_n "checking for sigsetjmp... " >&6; }
-if test "${pgac_cv_func_sigsetjmp+set}" = set; then
+{ $as_echo "$as_me:$LINENO: result: $ac_cv_func_syslog" >&5
+$as_echo "$ac_cv_func_syslog" >&6; }
+if test "x$ac_cv_func_syslog" = x""yes; then
+  if test "${ac_cv_header_syslog_h+set}" = set; then
+  { $as_echo "$as_me:$LINENO: checking for syslog.h" >&5
+$as_echo_n "checking for syslog.h... " >&6; }
+if test "${ac_cv_header_syslog_h+set}" = set; then
   $as_echo_n "(cached) " >&6
+fi
+{ $as_echo "$as_me:$LINENO: result: $ac_cv_header_syslog_h" >&5
+$as_echo "$ac_cv_header_syslog_h" >&6; }
 else
-  cat >conftest.$ac_ext <<_ACEOF
+  # Is the header compilable?
+{ $as_echo "$as_me:$LINENO: checking syslog.h usability" >&5
+$as_echo_n "checking syslog.h usability... " >&6; }
+cat >conftest.$ac_ext <<_ACEOF
 /* confdefs.h.  */
 _ACEOF
 cat confdefs.h >>conftest.$ac_ext
 cat >>conftest.$ac_ext <<_ACEOF
 /* end confdefs.h.  */
-#include <setjmp.h>
-int
-main ()
-{
-sigjmp_buf x; sigsetjmp(x, 1);
-  ;
-  return 0;
-}
+$ac_includes_default
+#include <syslog.h>
 _ACEOF
-rm -f conftest.$ac_objext conftest$ac_exeext
-if { (ac_try="$ac_link"
+rm -f conftest.$ac_objext
+if { (ac_try="$ac_compile"
 case "(($ac_try" in
   *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
   *) ac_try_echo=$ac_try;;
 esac
 eval ac_try_echo="\"\$as_me:$LINENO: $ac_try_echo\""
 $as_echo "$ac_try_echo") >&5
-  (eval "$ac_link") 2>conftest.er1
+  (eval "$ac_compile") 2>conftest.er1
   ac_status=$?
   grep -v '^ *+' conftest.er1 >conftest.err
   rm -f conftest.er1
@@ -22031,256 +21981,29 @@ $as_echo "$ac_try_echo") >&5
   (exit $ac_status); } && {
 	 test -z "$ac_c_werror_flag" ||
 	 test ! -s conftest.err
-       } && test -s conftest$ac_exeext && {
-	 test "$cross_compiling" = yes ||
-	 $as_test_x conftest$ac_exeext
-       }; then
-  pgac_cv_func_sigsetjmp=yes
+       } && test -s conftest.$ac_objext; then
+  ac_header_compiler=yes
 else
   $as_echo "$as_me: failed program was:" >&5
 sed 's/^/| /' conftest.$ac_ext >&5
 
-	pgac_cv_func_sigsetjmp=no
-fi
-
-rm -rf conftest.dSYM
-rm -f core conftest.err conftest.$ac_objext conftest_ipa8_conftest.oo \
-      conftest$ac_exeext conftest.$ac_ext
+	ac_header_compiler=no
 fi
-{ $as_echo "$as_me:$LINENO: result: $pgac_cv_func_sigsetjmp" >&5
-$as_echo "$pgac_cv_func_sigsetjmp" >&6; }
-if test x"$pgac_cv_func_sigsetjmp" = x"yes"; then
-
-cat >>confdefs.h <<\_ACEOF
-#define HAVE_SIGSETJMP 1
-_ACEOF
 
-fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+{ $as_echo "$as_me:$LINENO: result: $ac_header_compiler" >&5
+$as_echo "$ac_header_compiler" >&6; }
 
-{ $as_echo "$as_me:$LINENO: checking whether sys_siglist is declared" >&5
-$as_echo_n "checking whether sys_siglist is declared... " >&6; }
-if test "${ac_cv_have_decl_sys_siglist+set}" = set; then
-  $as_echo_n "(cached) " >&6
-else
-  cat >conftest.$ac_ext <<_ACEOF
+# Is the header present?
+{ $as_echo "$as_me:$LINENO: checking syslog.h presence" >&5
+$as_echo_n "checking syslog.h presence... " >&6; }
+cat >conftest.$ac_ext <<_ACEOF
 /* confdefs.h.  */
 _ACEOF
 cat confdefs.h >>conftest.$ac_ext
 cat >>conftest.$ac_ext <<_ACEOF
 /* end confdefs.h.  */
-#include <signal.h>
-/* NetBSD declares sys_siglist in unistd.h.  */
-#ifdef HAVE_UNISTD_H
-# include <unistd.h>
-#endif
-
-
-int
-main ()
-{
-#ifndef sys_siglist
-  (void) sys_siglist;
-#endif
-
-  ;
-  return 0;
-}
-_ACEOF
-rm -f conftest.$ac_objext
-if { (ac_try="$ac_compile"
-case "(($ac_try" in
-  *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
-  *) ac_try_echo=$ac_try;;
-esac
-eval ac_try_echo="\"\$as_me:$LINENO: $ac_try_echo\""
-$as_echo "$ac_try_echo") >&5
-  (eval "$ac_compile") 2>conftest.er1
-  ac_status=$?
-  grep -v '^ *+' conftest.er1 >conftest.err
-  rm -f conftest.er1
-  cat conftest.err >&5
-  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
-  (exit $ac_status); } && {
-	 test -z "$ac_c_werror_flag" ||
-	 test ! -s conftest.err
-       } && test -s conftest.$ac_objext; then
-  ac_cv_have_decl_sys_siglist=yes
-else
-  $as_echo "$as_me: failed program was:" >&5
-sed 's/^/| /' conftest.$ac_ext >&5
-
-	ac_cv_have_decl_sys_siglist=no
-fi
-
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
-fi
-{ $as_echo "$as_me:$LINENO: result: $ac_cv_have_decl_sys_siglist" >&5
-$as_echo "$ac_cv_have_decl_sys_siglist" >&6; }
-if test "x$ac_cv_have_decl_sys_siglist" = x""yes; then
-
-cat >>confdefs.h <<_ACEOF
-#define HAVE_DECL_SYS_SIGLIST 1
-_ACEOF
-
-
-else
-  cat >>confdefs.h <<_ACEOF
-#define HAVE_DECL_SYS_SIGLIST 0
-_ACEOF
-
-
-fi
-
-
-
-
-{ $as_echo "$as_me:$LINENO: checking for syslog" >&5
-$as_echo_n "checking for syslog... " >&6; }
-if test "${ac_cv_func_syslog+set}" = set; then
-  $as_echo_n "(cached) " >&6
-else
-  cat >conftest.$ac_ext <<_ACEOF
-/* confdefs.h.  */
-_ACEOF
-cat confdefs.h >>conftest.$ac_ext
-cat >>conftest.$ac_ext <<_ACEOF
-/* end confdefs.h.  */
-/* Define syslog to an innocuous variant, in case <limits.h> declares syslog.
-   For example, HP-UX 11i <limits.h> declares gettimeofday.  */
-#define syslog innocuous_syslog
-
-/* System header to define __stub macros and hopefully few prototypes,
-    which can conflict with char syslog (); below.
-    Prefer <limits.h> to <assert.h> if __STDC__ is defined, since
-    <limits.h> exists even on freestanding compilers.  */
-
-#ifdef __STDC__
-# include <limits.h>
-#else
-# include <assert.h>
-#endif
-
-#undef syslog
-
-/* Override any GCC internal prototype to avoid an error.
-   Use char because int might match the return type of a GCC
-   builtin and then its argument prototype would still apply.  */
-#ifdef __cplusplus
-extern "C"
-#endif
-char syslog ();
-/* The GNU C library defines this for functions which it implements
-    to always fail with ENOSYS.  Some functions are actually named
-    something starting with __ and the normal name is an alias.  */
-#if defined __stub_syslog || defined __stub___syslog
-choke me
-#endif
-
-int
-main ()
-{
-return syslog ();
-  ;
-  return 0;
-}
-_ACEOF
-rm -f conftest.$ac_objext conftest$ac_exeext
-if { (ac_try="$ac_link"
-case "(($ac_try" in
-  *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
-  *) ac_try_echo=$ac_try;;
-esac
-eval ac_try_echo="\"\$as_me:$LINENO: $ac_try_echo\""
-$as_echo "$ac_try_echo") >&5
-  (eval "$ac_link") 2>conftest.er1
-  ac_status=$?
-  grep -v '^ *+' conftest.er1 >conftest.err
-  rm -f conftest.er1
-  cat conftest.err >&5
-  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
-  (exit $ac_status); } && {
-	 test -z "$ac_c_werror_flag" ||
-	 test ! -s conftest.err
-       } && test -s conftest$ac_exeext && {
-	 test "$cross_compiling" = yes ||
-	 $as_test_x conftest$ac_exeext
-       }; then
-  ac_cv_func_syslog=yes
-else
-  $as_echo "$as_me: failed program was:" >&5
-sed 's/^/| /' conftest.$ac_ext >&5
-
-	ac_cv_func_syslog=no
-fi
-
-rm -rf conftest.dSYM
-rm -f core conftest.err conftest.$ac_objext conftest_ipa8_conftest.oo \
-      conftest$ac_exeext conftest.$ac_ext
-fi
-{ $as_echo "$as_me:$LINENO: result: $ac_cv_func_syslog" >&5
-$as_echo "$ac_cv_func_syslog" >&6; }
-if test "x$ac_cv_func_syslog" = x""yes; then
-  if test "${ac_cv_header_syslog_h+set}" = set; then
-  { $as_echo "$as_me:$LINENO: checking for syslog.h" >&5
-$as_echo_n "checking for syslog.h... " >&6; }
-if test "${ac_cv_header_syslog_h+set}" = set; then
-  $as_echo_n "(cached) " >&6
-fi
-{ $as_echo "$as_me:$LINENO: result: $ac_cv_header_syslog_h" >&5
-$as_echo "$ac_cv_header_syslog_h" >&6; }
-else
-  # Is the header compilable?
-{ $as_echo "$as_me:$LINENO: checking syslog.h usability" >&5
-$as_echo_n "checking syslog.h usability... " >&6; }
-cat >conftest.$ac_ext <<_ACEOF
-/* confdefs.h.  */
-_ACEOF
-cat confdefs.h >>conftest.$ac_ext
-cat >>conftest.$ac_ext <<_ACEOF
-/* end confdefs.h.  */
-$ac_includes_default
-#include <syslog.h>
-_ACEOF
-rm -f conftest.$ac_objext
-if { (ac_try="$ac_compile"
-case "(($ac_try" in
-  *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
-  *) ac_try_echo=$ac_try;;
-esac
-eval ac_try_echo="\"\$as_me:$LINENO: $ac_try_echo\""
-$as_echo "$ac_try_echo") >&5
-  (eval "$ac_compile") 2>conftest.er1
-  ac_status=$?
-  grep -v '^ *+' conftest.er1 >conftest.err
-  rm -f conftest.er1
-  cat conftest.err >&5
-  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
-  (exit $ac_status); } && {
-	 test -z "$ac_c_werror_flag" ||
-	 test ! -s conftest.err
-       } && test -s conftest.$ac_objext; then
-  ac_header_compiler=yes
-else
-  $as_echo "$as_me: failed program was:" >&5
-sed 's/^/| /' conftest.$ac_ext >&5
-
-	ac_header_compiler=no
-fi
-
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
-{ $as_echo "$as_me:$LINENO: result: $ac_header_compiler" >&5
-$as_echo "$ac_header_compiler" >&6; }
-
-# Is the header present?
-{ $as_echo "$as_me:$LINENO: checking syslog.h presence" >&5
-$as_echo_n "checking syslog.h presence... " >&6; }
-cat >conftest.$ac_ext <<_ACEOF
-/* confdefs.h.  */
-_ACEOF
-cat confdefs.h >>conftest.$ac_ext
-cat >>conftest.$ac_ext <<_ACEOF
-/* end confdefs.h.  */
-#include <syslog.h>
+#include <syslog.h>
 _ACEOF
 if { (ac_try="$ac_cpp conftest.$ac_ext"
 case "(($ac_try" in
@@ -22760,6 +22483,284 @@ _ACEOF
 
 fi
 
+# Lastly, restore full LIBS list and check for readline/libedit symbols
+LIBS="$LIBS_including_readline"
+
+if test "$with_readline" = yes; then
+  { $as_echo "$as_me:$LINENO: checking for rl_completion_append_character" >&5
+$as_echo_n "checking for rl_completion_append_character... " >&6; }
+if test "${pgac_cv_var_rl_completion_append_character+set}" = set; then
+  $as_echo_n "(cached) " >&6
+else
+  cat >conftest.$ac_ext <<_ACEOF
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+#include <stdio.h>
+#ifdef HAVE_READLINE_READLINE_H
+# include <readline/readline.h>
+#elif defined(HAVE_READLINE_H)
+# include <readline.h>
+#endif
+
+int
+main ()
+{
+rl_completion_append_character = 'x';
+  ;
+  return 0;
+}
+_ACEOF
+rm -f conftest.$ac_objext conftest$ac_exeext
+if { (ac_try="$ac_link"
+case "(($ac_try" in
+  *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
+  *) ac_try_echo=$ac_try;;
+esac
+eval ac_try_echo="\"\$as_me:$LINENO: $ac_try_echo\""
+$as_echo "$ac_try_echo") >&5
+  (eval "$ac_link") 2>conftest.er1
+  ac_status=$?
+  grep -v '^ *+' conftest.er1 >conftest.err
+  rm -f conftest.er1
+  cat conftest.err >&5
+  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } && {
+	 test -z "$ac_c_werror_flag" ||
+	 test ! -s conftest.err
+       } && test -s conftest$ac_exeext && {
+	 test "$cross_compiling" = yes ||
+	 $as_test_x conftest$ac_exeext
+       }; then
+  pgac_cv_var_rl_completion_append_character=yes
+else
+  $as_echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+	pgac_cv_var_rl_completion_append_character=no
+fi
+
+rm -rf conftest.dSYM
+rm -f core conftest.err conftest.$ac_objext conftest_ipa8_conftest.oo \
+      conftest$ac_exeext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:$LINENO: result: $pgac_cv_var_rl_completion_append_character" >&5
+$as_echo "$pgac_cv_var_rl_completion_append_character" >&6; }
+if test x"$pgac_cv_var_rl_completion_append_character" = x"yes"; then
+
+cat >>confdefs.h <<\_ACEOF
+#define HAVE_RL_COMPLETION_APPEND_CHARACTER 1
+_ACEOF
+
+fi
+
+
+for ac_func in rl_completion_matches rl_filename_completion_function
+do
+as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh`
+{ $as_echo "$as_me:$LINENO: checking for $ac_func" >&5
+$as_echo_n "checking for $ac_func... " >&6; }
+if { as_var=$as_ac_var; eval "test \"\${$as_var+set}\" = set"; }; then
+  $as_echo_n "(cached) " >&6
+else
+  cat >conftest.$ac_ext <<_ACEOF
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+/* Define $ac_func to an innocuous variant, in case <limits.h> declares $ac_func.
+   For example, HP-UX 11i <limits.h> declares gettimeofday.  */
+#define $ac_func innocuous_$ac_func
+
+/* System header to define __stub macros and hopefully few prototypes,
+    which can conflict with char $ac_func (); below.
+    Prefer <limits.h> to <assert.h> if __STDC__ is defined, since
+    <limits.h> exists even on freestanding compilers.  */
+
+#ifdef __STDC__
+# include <limits.h>
+#else
+# include <assert.h>
+#endif
+
+#undef $ac_func
+
+/* Override any GCC internal prototype to avoid an error.
+   Use char because int might match the return type of a GCC
+   builtin and then its argument prototype would still apply.  */
+#ifdef __cplusplus
+extern "C"
+#endif
+char $ac_func ();
+/* The GNU C library defines this for functions which it implements
+    to always fail with ENOSYS.  Some functions are actually named
+    something starting with __ and the normal name is an alias.  */
+#if defined __stub_$ac_func || defined __stub___$ac_func
+choke me
+#endif
+
+int
+main ()
+{
+return $ac_func ();
+  ;
+  return 0;
+}
+_ACEOF
+rm -f conftest.$ac_objext conftest$ac_exeext
+if { (ac_try="$ac_link"
+case "(($ac_try" in
+  *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
+  *) ac_try_echo=$ac_try;;
+esac
+eval ac_try_echo="\"\$as_me:$LINENO: $ac_try_echo\""
+$as_echo "$ac_try_echo") >&5
+  (eval "$ac_link") 2>conftest.er1
+  ac_status=$?
+  grep -v '^ *+' conftest.er1 >conftest.err
+  rm -f conftest.er1
+  cat conftest.err >&5
+  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } && {
+	 test -z "$ac_c_werror_flag" ||
+	 test ! -s conftest.err
+       } && test -s conftest$ac_exeext && {
+	 test "$cross_compiling" = yes ||
+	 $as_test_x conftest$ac_exeext
+       }; then
+  eval "$as_ac_var=yes"
+else
+  $as_echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+	eval "$as_ac_var=no"
+fi
+
+rm -rf conftest.dSYM
+rm -f core conftest.err conftest.$ac_objext conftest_ipa8_conftest.oo \
+      conftest$ac_exeext conftest.$ac_ext
+fi
+ac_res=`eval 'as_val=${'$as_ac_var'}
+		 $as_echo "$as_val"'`
+	       { $as_echo "$as_me:$LINENO: result: $ac_res" >&5
+$as_echo "$ac_res" >&6; }
+as_val=`eval 'as_val=${'$as_ac_var'}
+		 $as_echo "$as_val"'`
+   if test "x$as_val" = x""yes; then
+  cat >>confdefs.h <<_ACEOF
+#define `$as_echo "HAVE_$ac_func" | $as_tr_cpp` 1
+_ACEOF
+
+fi
+done
+
+
+
+for ac_func in append_history history_truncate_file
+do
+as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh`
+{ $as_echo "$as_me:$LINENO: checking for $ac_func" >&5
+$as_echo_n "checking for $ac_func... " >&6; }
+if { as_var=$as_ac_var; eval "test \"\${$as_var+set}\" = set"; }; then
+  $as_echo_n "(cached) " >&6
+else
+  cat >conftest.$ac_ext <<_ACEOF
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+/* Define $ac_func to an innocuous variant, in case <limits.h> declares $ac_func.
+   For example, HP-UX 11i <limits.h> declares gettimeofday.  */
+#define $ac_func innocuous_$ac_func
+
+/* System header to define __stub macros and hopefully few prototypes,
+    which can conflict with char $ac_func (); below.
+    Prefer <limits.h> to <assert.h> if __STDC__ is defined, since
+    <limits.h> exists even on freestanding compilers.  */
+
+#ifdef __STDC__
+# include <limits.h>
+#else
+# include <assert.h>
+#endif
+
+#undef $ac_func
+
+/* Override any GCC internal prototype to avoid an error.
+   Use char because int might match the return type of a GCC
+   builtin and then its argument prototype would still apply.  */
+#ifdef __cplusplus
+extern "C"
+#endif
+char $ac_func ();
+/* The GNU C library defines this for functions which it implements
+    to always fail with ENOSYS.  Some functions are actually named
+    something starting with __ and the normal name is an alias.  */
+#if defined __stub_$ac_func || defined __stub___$ac_func
+choke me
+#endif
+
+int
+main ()
+{
+return $ac_func ();
+  ;
+  return 0;
+}
+_ACEOF
+rm -f conftest.$ac_objext conftest$ac_exeext
+if { (ac_try="$ac_link"
+case "(($ac_try" in
+  *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
+  *) ac_try_echo=$ac_try;;
+esac
+eval ac_try_echo="\"\$as_me:$LINENO: $ac_try_echo\""
+$as_echo "$ac_try_echo") >&5
+  (eval "$ac_link") 2>conftest.er1
+  ac_status=$?
+  grep -v '^ *+' conftest.er1 >conftest.err
+  rm -f conftest.er1
+  cat conftest.err >&5
+  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } && {
+	 test -z "$ac_c_werror_flag" ||
+	 test ! -s conftest.err
+       } && test -s conftest$ac_exeext && {
+	 test "$cross_compiling" = yes ||
+	 $as_test_x conftest$ac_exeext
+       }; then
+  eval "$as_ac_var=yes"
+else
+  $as_echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+	eval "$as_ac_var=no"
+fi
+
+rm -rf conftest.dSYM
+rm -f core conftest.err conftest.$ac_objext conftest_ipa8_conftest.oo \
+      conftest$ac_exeext conftest.$ac_ext
+fi
+ac_res=`eval 'as_val=${'$as_ac_var'}
+		 $as_echo "$as_val"'`
+	       { $as_echo "$as_me:$LINENO: result: $ac_res" >&5
+$as_echo "$ac_res" >&6; }
+as_val=`eval 'as_val=${'$as_ac_var'}
+		 $as_echo "$as_val"'`
+   if test "x$as_val" = x""yes; then
+  cat >>confdefs.h <<_ACEOF
+#define `$as_echo "HAVE_$ac_func" | $as_tr_cpp` 1
+_ACEOF
+
+fi
+done
+
+fi
+
 
 #
 # Pthreads
diff --git a/configure.in b/configure.in
index 2dee4b392b1..fece090eeb6 100644
--- a/configure.in
+++ b/configure.in
@@ -1202,6 +1202,13 @@ PGAC_VAR_INT_TIMEZONE
 AC_FUNC_ACCEPT_ARGTYPES
 PGAC_FUNC_GETTIMEOFDAY_1ARG
 
+# Some versions of libedit contain strlcpy(), setproctitle(), and other
+# symbols that that library has no business exposing to the world.  Pending
+# acquisition of a clue by those developers, ignore libedit (including its
+# possible alias of libreadline) while checking for everything else.
+LIBS_including_readline="$LIBS"
+LIBS=`echo "$LIBS" | sed -e 's/-ledit//g' -e 's/-lreadline//g'`
+
 AC_CHECK_FUNCS([cbrt dlopen fdatasync getifaddrs getpeerucred getrlimit mbstowcs_l memmove poll pstat readlink setproctitle setsid sigprocmask symlink sync_file_range towlower utime utimes wcstombs wcstombs_l])
 
 AC_REPLACE_FUNCS(fseeko)
@@ -1316,11 +1323,6 @@ else
   AC_CHECK_FUNCS([fpclass fp_class fp_class_d class], [break])
 fi
 
-# Some versions of libedit contain strlcpy(); so disregard that library while
-# checking for these standard libc functions.
-pgac_save_LIBS="$LIBS"
-LIBS=`echo "$LIBS" | sed -e 's/-ledit//g' -e 's/-lreadline//g'`
-
 AC_REPLACE_FUNCS([crypt fls getopt getrusage inet_aton random rint srandom strerror strlcat strlcpy])
 
 case $host_os in
@@ -1338,9 +1340,6 @@ case $host_os in
 		;;
 esac
 
-
-LIBS="$pgac_save_LIBS"
-
 # System's version of getaddrinfo(), if any, may be used only if we found
 # a definition for struct addrinfo; see notes in src/include/getaddrinfo.h.
 # (Note: the AC_REPLACE_FUNCS probe fails on Windows, where the available
@@ -1394,13 +1393,6 @@ else
   AC_SUBST(have_win32_dbghelp,no)
 fi
 
-if test "$with_readline" = yes; then
-  PGAC_VAR_RL_COMPLETION_APPEND_CHARACTER
-  AC_CHECK_FUNCS([rl_completion_matches rl_filename_completion_function])
-  AC_CHECK_FUNCS([append_history history_truncate_file])
-fi
-
-
 dnl Cannot use AC_CHECK_FUNC because sigsetjmp may be a macro
 dnl (especially on GNU libc)
 dnl See also comments in c.h.
@@ -1451,6 +1443,15 @@ if test x"$pgac_cv_gcc_int_atomics" = x"yes"; then
   AC_DEFINE(HAVE_GCC_INT_ATOMICS, 1, [Define to 1 if you have __sync_lock_test_and_set(int *) and friends.])
 fi
 
+# Lastly, restore full LIBS list and check for readline/libedit symbols
+LIBS="$LIBS_including_readline"
+
+if test "$with_readline" = yes; then
+  PGAC_VAR_RL_COMPLETION_APPEND_CHARACTER
+  AC_CHECK_FUNCS([rl_completion_matches rl_filename_completion_function])
+  AC_CHECK_FUNCS([append_history history_truncate_file])
+fi
+
 
 #
 # Pthreads
-- 
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