warning from configuring openssh-6.0p1

[Support Team]

When running "configure" for openssh-6.0p1 , I got the following output from
"configure":


configure: WARNING: linux/filter.h: present but cannot be compiled
configure: WARNING: linux/filter.h:     check for missing prerequisite
headers?
configure: WARNING: linux/filter.h: see the Autoconf documentation
configure: WARNING: linux/filter.h:     section "Present But Cannot Be
Compiled"
configure: WARNING: linux/filter.h: proceeding with the compiler's result
configure: WARNING:     ## ------------------------------------------- ##
configure: WARNING:     ## Report this to openssh-unix-dev at mindrot.org ##
configure: WARNING:     ## ------------------------------------------- ##
checking for linux/filter.h... no

I can still successfully make and the "sshd" that is made appears to run
fine.

The build machine is a Red Hat 9 machine running  linux 2.4.20-8smp .  More
from
"config.log" ....


configure:6925: checking linux/filter.h usability
configure:6925: gcc -c -g -O2 -Wall -Wpointer-arith -Wuninitialized
-Wsign-compare -Wformat-security -fno-strict-aliasing -D_FORTIFY_SOURCE=2
-fno-builtin-memset -std=gnu99 -I /usr/src/ssl/openssl/include conftest.c
>&5
In file included from conftest.c:108:
/usr/include/linux/filter.h:21: error: parse error before "__u16"
/usr/include/linux/filter.h:23: error: parse error before "jf"
/usr/include/linux/filter.h:24: error: parse error before "k"
configure:6925: $? = 1
configure: failed program was:
| /* confdefs.h */
| #define PACKAGE_NAME "OpenSSH"
| #define PACKAGE_TARNAME "openssh"
| #define PACKAGE_VERSION "Portable"
| #define PACKAGE_STRING "OpenSSH Portable"
| #define PACKAGE_BUGREPORT "openssh-unix-dev at mindrot.org"
| #define PACKAGE_URL ""
| #define STDC_HEADERS 1
| #define HAVE_SYS_TYPES_H 1
| #define HAVE_SYS_STAT_H 1
| #define HAVE_STDLIB_H 1
| #define HAVE_STRING_H 1
| #define HAVE_MEMORY_H 1
| #define HAVE_STRINGS_H 1
| #define HAVE_INTTYPES_H 1
| #define HAVE_STDINT_H 1
| #define HAVE_UNISTD_H 1
| #define _FILE_OFFSET_BITS 64
| #define LOGIN_PROGRAM_FALLBACK "/bin/login"
| #define _PATH_PASSWD_PROG "/usr/bin/passwd"
| #define HAVE_RLIMIT_NPROC /**/
| #define HAVE_ATTRIBUTE__NONNULL__ 1
| #define HAVE_CRYPT_H 1
| #define HAVE_DIRENT_H 1
| #define HAVE_ENDIAN_H 1
| #define HAVE_FEATURES_H 1
| #define HAVE_FCNTL_H 1
| #define HAVE_GETOPT_H 1
| #define HAVE_GLOB_H 1
| #define HAVE_LIMITS_H 1
| #define HAVE_NETDB_H 1
| #define HAVE_PATHS_H 1
| #define HAVE_POLL_H 1
| #define HAVE_PTY_H 1
| #define HAVE_RPC_TYPES_H 1
| #define HAVE_SECURITY_PAM_APPL_H 1
| #define HAVE_SHADOW_H 1
| #define HAVE_STDDEF_H 1
| #define HAVE_STDINT_H 1
| #define HAVE_STRING_H 1
| #define HAVE_STRINGS_H 1
| #define HAVE_SYS_BITYPES_H 1
| #define HAVE_SYS_CDEFS_H 1
| #define HAVE_SYS_DIR_H 1
| #define HAVE_SYS_MMAN_H 1
| #define HAVE_SYS_POLL_H 1
| #define HAVE_SYS_PRCTL_H 1
| #define HAVE_SYS_SELECT_H 1
| #define HAVE_SYS_STAT_H 1
| #define HAVE_SYS_STROPTS_H 1
| #define HAVE_SYS_STATVFS_H 1
| #define HAVE_SYS_SYSMACROS_H 1
| #define HAVE_SYS_TIME_H 1
| #define HAVE_SYS_UN_H 1
| #define HAVE_TIME_H 1
| #define HAVE_TTYENT_H 1
| #define HAVE_UNISTD_H 1
| #define HAVE_UTIME_H 1
| #define HAVE_UTMP_H 1
| #define HAVE_UTMPX_H 1
| #define HAVE_LASTLOG_H 1
| #define HAVE_SYS_MOUNT_H 1
| #define PAM_TTY_KLUDGE 1
| #define LOCKED_PASSWD_PREFIX "!"
| #define SPT_TYPE SPT_REUSEARGV
| #define LINK_OPNOTSUPP_ERRNO EPERM
| #define _PATH_BTMP "/var/log/btmp"
| #define USE_BTMP 1
| #define LINUX_OOM_ADJUST 1
| #define HAVE_LINUX_IF_TUN_H 1
| #define SSH_TUN_LINUX 1
| #define SSH_TUN_COMPAT_AF 1
| #define SSH_TUN_PREPEND_AF 1
| /* end confdefs.h.  */
| #include <stdio.h>
| #ifdef HAVE_SYS_TYPES_H
| # include <sys/types.h>
| #endif
| #ifdef HAVE_SYS_STAT_H
| # include <sys/stat.h>
| #endif
| #ifdef STDC_HEADERS
| # include <stdlib.h>
| # include <stddef.h>
| #else
| # ifdef HAVE_STDLIB_H
| #  include <stdlib.h>
| # endif
| #endif
| #ifdef HAVE_STRING_H
| # if !defined STDC_HEADERS && defined HAVE_MEMORY_H
| #  include <memory.h>
| # endif
| # include <string.h>
| #endif
| #ifdef HAVE_STRINGS_H
| # include <strings.h>
| #endif
| #ifdef HAVE_INTTYPES_H
| # include <inttypes.h>
| #endif
| #ifdef HAVE_STDINT_H
| # include <stdint.h>
| #endif
| #ifdef HAVE_UNISTD_H
| # include <unistd.h>
| #endif
| #include <linux/filter.h>
configure:6925: result: no
configure:6925: checking linux/filter.h presence
configure:6925: gcc -E -I /usr/src/ssl/openssl/include conftest.c
configure:6925: $? = 0
configure:6925: result: yes
configure:6925: WARNING: linux/filter.h: present but cannot be compiled
configure:6925: WARNING: linux/filter.h:     check for missing prerequisite
headers?
configure:6925: WARNING: linux/filter.h: see the Autoconf documentation
configure:6925: WARNING: linux/filter.h:     section "Present But Cannot Be
Compiled"
configure:6925: WARNING: linux/filter.h: proceeding with the compiler's
result
configure:6925: checking for linux/filter.h
configure:6925: result: no
configure:6925: checking linux/audit.h usability