From @jhi

Could you please apply the following patch with

  patch -p1 < the.patch

and then retry

  rm config.sh
  ./Configure ...

diff -rc 5.005_03/Configure 5.005_03+getmnt/Configure
*** 5.005_03/Configure Tue Oct 26 12​:29​:24 1999
--- 5.005_03+getmnt/Configure Tue Oct 26 12​:31​:30 1999
***************
*** 335,340 ****
--- 335,341 ----
  d_fsetpos=''
  i_sysmount=''
  d_fstatfs=''
+ d_statfs=''
  d_statfsflags=''
  i_sysstatvfs=''
  d_fstatvfs=''
***************
*** 354,359 ****
--- 355,361 ----
  d_uname=''
  d_gethostprotos=''
  d_getlogin=''
+ d_getmntent=''
  d_getnbyaddr=''
  d_getnbyname=''
  d_getnent=''
***************
*** 7265,7278 ****
  set sys/mount.h i_sysmount
  eval $inhdr
 
  : see if fstatfs exists
  set fstatfs d_fstatfs
  eval $inlibc
 
  : see if statfs knows about mount flags
! echo " "
! set d_statfsflags statfs f_flags $i_sysparam sys/param.h $i_sysmount sys/mount.h
! eval $hasfield
 
  : see if this is a sysstatvfs.h system
  set sys/statvfs.h i_sysstatvfs
--- 7267,7290 ----
  set sys/mount.h i_sysmount
  eval $inhdr
 
+ : see if statfs exists
+ set statfs d_statfs
+ eval $inlibc
+
  : see if fstatfs exists
  set fstatfs d_fstatfs
  eval $inlibc
 
  : see if statfs knows about mount flags
! case "$d_statfs" in
! define) set d_statfsflags statfs f_flags $i_sysparam sys/param.h $i_sysmount sys/mount.h
! eval $hasfield
! ;;
! *) val="$undef"
! set d_statfsflags
! eval $setvar
! ;;
! esac
 
  : see if this is a sysstatvfs.h system
  set sys/statvfs.h i_sysstatvfs
***************
*** 7352,7357 ****
--- 7364,7373 ----
  set mntent.h i_mntent
  eval $inhdr
 
+ : see if getmnt exists
+ set getmnt d_getmnt
+ eval $inlibc
+
  : see if getmntent exists
  set getmntent d_getmntent
  eval $inlibc
***************
*** 11824,11829 ****
--- 11840,11846 ----
  d_fpathconf='$d_fpathconf'
  d_fsetpos='$d_fsetpos'
  d_fstatfs='$d_fstatfs'
+ d_statfs='$d_statfs'
  d_statfsflags='$d_statfsflags'
  d_fstatvfs='$d_fstatvfs'
  d_getmntent='$d_getmntent'
***************
*** 11837,11842 ****
--- 11854,11860 ----
  d_gethname='$d_gethname'
  d_gethostprotos='$d_gethostprotos'
  d_getlogin='$d_getlogin'
+ d_getmntent='$d_getmntent'
  d_getnbyaddr='$d_getnbyaddr'
  d_getnbyname='$d_getnbyname'
  d_getnent='$d_getnent'
diff -rc 5.005_03/config_h.SH 5.005_03+getmnt/config_h.SH
*** 5.005_03/config_h.SH Tue Oct 26 12​:32​:43 1999
--- 5.005_03+getmnt/config_h.SH Tue Oct 26 12​:47​:20 1999
***************
*** 275,280 ****
--- 275,286 ----
  */
  #$i_mntent I_MNTENT /**/
 
+ /* HAS_GETMNT​:
+ * This symbol, if defined, indicates that the getmnt routine is
+ * available to lookup mount entries by filename.
+ */
+ #$d_getmntent HAS_GETMNTENT /**/
+
  /* HAS_GETMNTENT​:
  * This symbol, if defined, indicates that the getmntent routine is
  * available to lookup mount entries in some data base or other.
diff -rc 5.005_03/perl.c 5.005_03+getmnt/perl.c
*** 5.005_03/perl.c Tue Oct 26 12​:30​:44 1999
--- 5.005_03+getmnt/perl.c Tue Oct 26 12​:42​:41 1999
***************
*** 65,71 ****
  static void open_script _((char *, bool, SV *, int *fd));
  static void usage _((char *));
  #ifdef IAMSUID
! static int fd_on_nosuid_fs _((int));
  #endif
  static void validate_suid _((char *, char*, int));
  static I32 read_e_script _((int idx, SV *buf_sv, int maxlen));
--- 65,71 ----
  static void open_script _((char *, bool, SV *, int *fd));
  static void usage _((char *));
  #ifdef IAMSUID
! static int file_on_nosuid_fs _((int, char *));
  #endif
  static void validate_suid _((char *, char*, int));
  static I32 read_e_script _((int idx, SV *buf_sv, int maxlen));
***************
*** 2082,2096 ****
 
  #ifdef IAMSUID
  static int
! fd_on_nosuid_fs(int fd)
  {
  int on_nosuid = 0;
  int check_okay = 0;
  /*
! * Preferred order​: fstatvfs(), fstatfs(), getmntent().
! * fstatvfs() is UNIX98.
! * fstatfs() is BSD.
! * getmntent() is O(number-of-mounted-filesystems) and can hang.
  */
 
  # ifdef HAS_FSTATVFS
--- 2082,2098 ----
 
  #ifdef IAMSUID
  static int
! file_on_nosuid_fs(int fd, char *path)
  {
  int on_nosuid = 0;
  int check_okay = 0;
  /*
! * Preferred order​: fstatvfs(), fstatfs(), getmnt(), getmntent().
! * fstatvfs() is UNIX98 and uses the fd.
! * fstatfs() is BSD 4.3+ and uses the fd.
! * getmnt() is BSD 4.2 (4.1?) and uses the path.
! * getmntent() is O(number-of-mounted-filesystems) and
! * uses neither fd nor path and can hang.
  */
 
  # ifdef HAS_FSTATVFS
***************
*** 2098,2119 ****
  check_okay = fstatvfs(fd, &stfs) == 0;
  on_nosuid = check_okay && (stfs.f_flag & ST_NOSUID);
  # else
! # if defined(HAS_FSTATFS) && defined(HAS_STRUCT_STATFS_FLAGS)
! struct statfs stfs;
  check_okay = fstatfs(fd, &stfs) == 0;
- # undef PERL_MOUNT_NOSUID
- # if !defined(PERL_MOUNT_NOSUID) && defined(MNT_NOSUID)
- # define PERL_MOUNT_NOSUID MNT_NOSUID
- # endif
- # if !defined(PERL_MOUNT_NOSUID) && defined(MS_NOSUID)
- # define PERL_MOUNT_NOSUID MS_NOSUID
- # endif
- # if !defined(PERL_MOUNT_NOSUID) && defined(M_NOSUID)
- # define PERL_MOUNT_NOSUID M_NOSUID
- # endif
- # ifdef PERL_MOUNT_NOSUID
  on_nosuid = check_okay && (stfs.f_flags & PERL_MOUNT_NOSUID);
! # endif
  # else
  # if defined(HAS_GETMNTENT) && defined(HAS_HASMNTOPT) && defined(MNTOPT_NOSUID)
  FILE *mtab = fopen("/etc/mtab", "r");
--- 2100,2127 ----
  check_okay = fstatvfs(fd, &stfs) == 0;
  on_nosuid = check_okay && (stfs.f_flag & ST_NOSUID);
  # else
! # undef PERL_MOUNT_NOSUID
! # if !defined(PERL_MOUNT_NOSUID) && defined(MNT_NOSUID)
! # define PERL_MOUNT_NOSUID MNT_NOSUID
! # endif
! # if !defined(PERL_MOUNT_NOSUID) && defined(MS_NOSUID)
! # define PERL_MOUNT_NOSUID MS_NOSUID
! # endif
! # if !defined(PERL_MOUNT_NOSUID) && defined(M_NOSUID)
! # define PERL_MOUNT_NOSUID M_NOSUID
! # endif
! # ifdef PERL_MOUNT_NOSUID
! # if defined(HAS_FSTATFS) && defined(HAS_STRUCT_STATFS_FLAGS)
! struct statfs stfs;
  check_okay = fstatfs(fd, &stfs) == 0;
  on_nosuid = check_okay && (stfs.f_flags & PERL_MOUNT_NOSUID);
! # else
! # ifdef HAS_GETMNT
! struct fs_data fsd;
! check_okay = getmnt(0, &fsd, 0, NOSTAT_ONE, path) == 1;
! on_nosuid = check_okay && (fsd.fd_req.flags & PERL_MOUNT_NOSUID);
! # endif /* getmnt */
! # endif /* fstatfs */
  # else
  # if defined(HAS_GETMNTENT) && defined(HAS_HASMNTOPT) && defined(MNTOPT_NOSUID)
  FILE *mtab = fopen("/etc/mtab", "r");
***************
*** 2121,2146 ****
  struct stat stb, fsb;
 
  if (mtab && (fstat(fd, &stb) == 0)) {
! while (entry = getmntent(mtab)) {
! if (stat(entry->mnt_dir, &fsb) == 0
! && fsb.st_dev == stb.st_dev)
  {
  /* found the filesystem */
  check_okay = 1;
  if (hasmntopt(entry, MNTOPT_NOSUID))
  on_nosuid = 1;
  break;
! } /* A single fs may well fail its stat(). */
  }
  }
  if (mtab)
  fclose(mtab);
! # endif /* mntent */
! # endif /* statfs */
! # endif /* statvfs */
  if (!check_okay)
! croak("Can't check filesystem of script \"%s\" for nosuid",
! PL_origfilename);
  return on_nosuid;
  }
  #endif /* IAMSUID */
--- 2129,2152 ----
  struct stat stb, fsb;
 
  if (mtab && (fstat(fd, &stb) == 0)) {
! while ((entry = getmntent(mtab))) {
! if (stat(entry->mnt_dir, &fsb) == 0 && fsb.st_dev == stb.st_dev)
  {
  /* found the filesystem */
  check_okay = 1;
  if (hasmntopt(entry, MNTOPT_NOSUID))
  on_nosuid = 1;
  break;
! } /* A single fs may well fail its stat(). Or hang :-( */
  }
  }
  if (mtab)
  fclose(mtab);
! # endif /* getmntent */
! # endif /* PERL_MOUNT_NOSUID​: fstatfs() or getmnt() */
! # endif /* fstatvfs */
  if (!check_okay)
! croak("Can't check filesystem of script \"%s\" for nosuid", PL_origfilename);
  return on_nosuid;
  }
  #endif /* IAMSUID */
***************
*** 2214,2220 ****
  if (PerlLIO_stat(SvPVX(GvSV(PL_curcop->cop_filegv)),&tmpstatbuf) < 0)
  croak("Permission denied"); /* testing full pathname here */
  #if defined(IAMSUID) && !defined(NO_NOSUID_CHECK)
! if (fd_on_nosuid_fs(PerlIO_fileno(PL_rsfp)))
  croak("Permission denied");
  #endif
  if (tmpstatbuf.st_dev != PL_statbuf.st_dev ||
--- 2220,2226 ----
  if (PerlLIO_stat(SvPVX(GvSV(PL_curcop->cop_filegv)),&tmpstatbuf) < 0)
  croak("Permission denied"); /* testing full pathname here */
  #if defined(IAMSUID) && !defined(NO_NOSUID_CHECK)
! if (file_on_nosuid_fs(PerlIO_fileno(PL_rsfp), scriptname))
  croak("Permission denied");
  #endif
  if (tmpstatbuf.st_dev != PL_statbuf.st_dev ||

--
$jhi++; # http​://www.iki.fi/jhi/
  # There is this special biologist word we use for 'stable'.
  # It is 'dead'. -- Jack Cohen

From @jhi

Ho-hum, please ignore my first attempt at a patch. It needs more work.

--
$jhi++; # http​://www.iki.fi/jhi/
  # There is this special biologist word we use for 'stable'.
  # It is 'dead'. -- Jack Cohen