spurious request to report bug?

[Dave Love]

When configuring the current Emacs source on SunOS 4.1.4 with the
bundled cc, configure says this from an AC_CHECK_HEADERS check for
sys/resource.h done with autoconf 2.57:

  checking sys/resource.h usability... no
  checking sys/resource.h presence... yes
  configure: WARNING: sys/resource.h: present but cannot be compiled
  configure: WARNING: sys/resource.h: check for missing prerequisite headers?
  configure: WARNING: sys/resource.h: proceeding with the preprocessor's result
  configure: WARNING:     ## ------------------------------------ ##
  configure: WARNING:     ## Report this to address@hidden ##
  configure: WARNING:     ## ------------------------------------ ##
  checking for sys/resource.h... yes

I'm surprised it says to report a bug against autoconf.  (I'll fix the
issue in Emacs by using sys/time.h.)  The relevant config.log fragment
is:

  configure:5166: checking sys/resource.h usability
  configure:5166: cc -c -g     conftest.c >&5
  "/usr/include/sys/resource.h", line 25: undefined structure or union
  "/usr/include/sys/resource.h", line 26: undefined structure or union
  "/usr/include/sys/resource.h", line 43: undefined structure or union
  "/usr/include/sys/resource.h", line 43: undefined structure or union
  "/usr/include/sys/resource.h", line 43: undefined structure or union
  "/usr/include/sys/resource.h", line 43: undefined structure or union
  configure:5166: $? = 1
  configure: failed program was:
  | #line 5166 "configure"
  | /* confdefs.h.  */
  | 
  | #define PACKAGE_NAME ""
  | #define PACKAGE_TARNAME ""
  | #define PACKAGE_VERSION ""
  | #define PACKAGE_STRING ""
  | #define PACKAGE_BUGREPORT ""
  | #define MAIL_USE_POP 1
  | #define _GNU_SOURCE 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_UNISTD_H 1
  | #define HAVE_SYS_TIMEB_H 1
  | #define HAVE_SYS_TIME_H 1
  | #define HAVE_UNISTD_H 1
  | #define HAVE_UTIME_H 1
  | #define HAVE_TERMIOS_H 1
  | #define HAVE_LIMITS_H 1
  | #define HAVE_STRING_H 1
  | #define HAVE_STDLIB_H 1
  | #define HAVE_FCNTL_H 1
  | #define HAVE_STRINGS_H 1
  | #define HAVE_SYS_MMAN_H 1
  | #define HAVE_SYS_PARAM_H 1
  | #define HAVE_SYS_VLIMIT_H 1
  | /* end confdefs.h.  */
  | #include <stdio.h>
  | #if HAVE_SYS_TYPES_H
  | # include <sys/types.h>
  | #endif
  | #if HAVE_SYS_STAT_H
  | # include <sys/stat.h>
  | #endif
  | #if STDC_HEADERS
  | # include <stdlib.h>
  | # include <stddef.h>
  | #else
  | # if HAVE_STDLIB_H
  | #  include <stdlib.h>
  | # endif
  | #endif
  | #if HAVE_STRING_H
  | # if !STDC_HEADERS && HAVE_MEMORY_H
  | #  include <memory.h>
  | # endif
  | # include <string.h>
  | #endif
  | #if HAVE_STRINGS_H
  | # include <strings.h>
  | #endif
  | #if HAVE_INTTYPES_H
  | # include <inttypes.h>
  | #else
  | # if HAVE_STDINT_H
  | #  include <stdint.h>
  | # endif
  | #endif
  | #if HAVE_UNISTD_H
  | # include <unistd.h>
  | #endif
  | #include <sys/resource.h>
  configure:5166: result: no
  configure:5166: checking sys/resource.h presence
  configure:5166: /usr/lib/cpp    conftest.c
  configure:5166: $? = 0
  configure:5166: result: yes
  configure:5166: WARNING: sys/resource.h: present but cannot be compiled
  configure:5166: WARNING: sys/resource.h: check for missing prerequisite 
headers?
  configure:5166: WARNING: sys/resource.h: proceeding with the preprocessor's 
result
  configure:5166: checking for sys/resource.h
  configure:5166: result: yes