ttps://www.sudo.ws/pipermail/sudo-workers/2023-April/001387.html
https://github.com/sudo-project/sudo/commit/b83140e0f18fb27d310a4839a14f5c3febd2770b
https://github.com/sudo-project/sudo/commit/075ee0f9dc234f9a7e680b16304809e5546965d5

From b83140e0f18fb27d310a4839a14f5c3febd2770b Mon Sep 17 00:00:00 2001
From: "Todd C. Miller" <Todd.Miller@sudo.ws>
Date: Wed, 26 Apr 2023 11:10:46 -0600
Subject: [PATCH] Use ldap_msgfree() instead of ldap_init() for the lber.h
 test. The ldap_init() function is marked as deprecated and not defined by
 default on some systems.  This can cause an error for compilers that do not
 support implicit function declarations. From Florian Weimer.

--- a/configure
+++ b/configure
@@ -31515,7 +31515,7 @@ else case e in #(
 int
 main (void)
 {
-(void)ldap_init(0, 0)
+return ldap_msgfree(NULL)
   ;
   return 0;
 }
--- a/m4/ldap.m4
+++ b/m4/ldap.m4
@@ -52,7 +52,7 @@ AC_DEFUN([SUDO_CHECK_LDAP], [
 #include <lber.h>])
 	AC_CACHE_CHECK([whether lber.h is needed when including ldap.h], [sudo_cv_header_lber_h], [
 	    AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include <sys/types.h>
-#include <ldap.h>]], [[(void)ldap_init(0, 0)]])], [
+#include <ldap.h>]], [[return ldap_msgfree(NULL)]])], [
 		# No need to explicitly include lber.h when including ldap.h.
 		sudo_cv_header_lber_h=no
 	    ], [

From 075ee0f9dc234f9a7e680b16304809e5546965d5 Mon Sep 17 00:00:00 2001
From: "Todd C. Miller" <Todd.Miller@sudo.ws>
Date: Wed, 26 Apr 2023 12:44:10 -0600
Subject: [PATCH] Add missing stdio.h include for the _FORTIFY_SOURCE=2 check.
 Implementations of _FORTIFY_SOURCE require the header file to be included. 
 Also remove the useless test of an empty program with _FORTIFY_SOURCE
 defined.  Pointed out by Florian Weimer.

--- a/configure
+++ b/configure
@@ -34207,33 +34207,11 @@ else case e in #(
   e) cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
-
-int
-main (void)
-{
-char buf[4]; (void)sprintf(buf, "%s", "foo");
-
-  ;
-  return 0;
-}
-_ACEOF
-if ac_fn_c_try_link "$LINENO"
-then :
-  sudo_cv_use_fortify_source=yes
-else case e in #(
-  e) sudo_cv_use_fortify_source=no
-		 ;;
-esac
-fi
-rm -f core conftest.err conftest.$ac_objext conftest.beam \
-    conftest$ac_exeext conftest.$ac_ext
-
-	    cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-
+		    #include <stdio.h>
 int
 main (void)
 {
+char buf[4]; sprintf(buf, "%s", "foo"); return buf[0];
 
   ;
   return 0;
--- a/m4/hardening.m4
+++ b/m4/hardening.m4
@@ -10,18 +10,13 @@ AC_DEFUN([SUDO_CHECK_HARDENING], [
 	    [sudo_cv_use_fortify_source],
 	    [AC_LINK_IFELSE([
 		    AC_LANG_PROGRAM(
-			[[]], [[char buf[4]; (void)sprintf(buf, "%s", "foo");]]
+			[[#include <stdio.h>]],
+			[[char buf[4]; sprintf(buf, "%s", "foo"); return buf[0];]]
 		    )],
 		    [sudo_cv_use_fortify_source=yes],
 		    [sudo_cv_use_fortify_source=no]
 		)
 	    ]
-	    [AC_LINK_IFELSE(
-		[AC_LANG_PROGRAM([[]], [[]])],
-		    [sudo_cv_use_fortify_source=yes],
-		    [sudo_cv_use_fortify_source=no]
-		)
-	    ]
 	)
 	if test "$sudo_cv_use_fortify_source" != yes; then
 	    CPPFLAGS="$O_CPPFLAGS"