diff -uap httpd-2.4.25/acinclude.m4.detectsystemd httpd-2.4.25/acinclude.m4
diff -uap httpd-2.4.25/acinclude.m4.detectsystemd httpd-2.4.25/acinclude.m4
diff -uap httpd-2.4.25/acinclude.m4.detectsystemd httpd-2.4.25/acinclude.m4
--- httpd-2.4.25/acinclude.m4.detectsystemd
+++ httpd-2.4.25/acinclude.m4
@@ -604,6 +604,30 @@
   fi
 ])
 
+AC_DEFUN(APACHE_CHECK_SYSTEMD, [                                                                        
+dnl Check for systemd support for listen.c's socket activation.
+case $host in
+*-linux-*)
+   if test -n "$PKGCONFIG" && $PKGCONFIG --exists libsystemd; then
+      SYSTEMD_LIBS=`$PKGCONFIG --libs libsystemd`
+   elif test -n "$PKGCONFIG" && $PKGCONFIG --exists libsystemd-daemon; then
+      SYSTEMD_LIBS=`$PKGCONFIG --libs libsystemd-daemon`
+   else
+      AC_CHECK_LIB(systemd-daemon, sd_notify, SYSTEMD_LIBS="-lsystemd-daemon")
+   fi
+   if test -n "$SYSTEMD_LIBS"; then
+      AC_CHECK_HEADERS(systemd/sd-daemon.h)
+      if test "${ac_cv_header_systemd_sd_daemon_h}" = "no" || test -z "${SYSTEMD_LIBS}"; then
+        AC_MSG_WARN([Your system does not support systemd.])
+      else
+        APR_ADDTO(HTTPD_LIBS, [$SYSTEMD_LIBS])
+        AC_DEFINE(HAVE_SYSTEMD, 1, [Define if systemd is supported])
+      fi
+   fi
+   ;;
+esac
+])
+
 dnl
 dnl APACHE_EXPORT_ARGUMENTS
 dnl Export (via APACHE_SUBST) the various path-related variables that
diff -uap httpd-2.4.25/configure.in.detectsystemd httpd-2.4.25/configure.in
--- httpd-2.4.25/configure.in.detectsystemd
+++ httpd-2.4.25/configure.in
@@ -234,6 +234,7 @@
   AC_MSG_NOTICE([Using external PCRE library from $PCRE_CONFIG])
   APR_ADDTO(PCRE_INCLUDES, [`$PCRE_CONFIG --cflags`])
   APR_ADDTO(PCRE_LIBS, [`$PCRE_CONFIG --libs`])
+  APR_ADDTO(HTTPD_LIBS, [\$(PCRE_LIBS)])
 else
   AC_MSG_ERROR([pcre-config for libpcre not found. PCRE is required and available from http://pcre.org/])
 fi
@@ -504,6 +510,8 @@
     AC_DEFINE(HAVE_GMTOFF, 1, [Define if struct tm has a tm_gmtoff field])
 fi
 
+APACHE_CHECK_SYSTEMD
+
 dnl ## Set up any appropriate OS-specific environment variables for apachectl
 
 case $host in
@@ -668,6 +676,7 @@
 APACHE_SUBST(BUILTIN_LIBS)
 APACHE_SUBST(SHLIBPATH_VAR)
 APACHE_SUBST(OS_SPECIFIC_VARS)
+APACHE_SUBST(HTTPD_LIBS)
 
 PRE_SHARED_CMDS='echo ""'
 POST_SHARED_CMDS='echo ""'
--- httpd-2.4.25/Makefile.in.detectsystemd
+++ httpd-2.4.25/Makefile.in
@@ -4,7 +4,7 @@
 
 PROGRAM_NAME         = $(progname)
 PROGRAM_SOURCES      = modules.c
-PROGRAM_LDADD        = buildmark.o $(HTTPD_LDFLAGS) $(PROGRAM_DEPENDENCIES) $(PCRE_LIBS) $(EXTRA_LIBS) $(AP_LIBS) $(LIBS)
+PROGRAM_LDADD        = buildmark.o $(HTTPD_LDFLAGS) $(PROGRAM_DEPENDENCIES) $(HTTPD_LIBS) $(EXTRA_LIBS) $(AP_LIBS) $(LIBS)
 PROGRAM_PRELINK      = $(COMPILE) -c $(top_srcdir)/server/buildmark.c
 PROGRAM_DEPENDENCIES = \
   server/libmain.la \