[2.7] closes bpo-34652: Always disable lchmod on Linux. (GH-9242)

(cherry picked from commit 40caa05fa4d1810a1a6bfc34e0ec930c351089b7)

Co-authored-by: Benjamin Peterson <benjamin@python.org>
diff --git a/configure b/configure
index 03b73c6..505f8bb 100755
--- a/configure
+++ b/configure
@@ -769,6 +769,7 @@
 docdir
 oldincludedir
 includedir
+runstatedir
 localstatedir
 sharedstatedir
 sysconfdir
@@ -880,6 +881,7 @@
 sysconfdir='${prefix}/etc'
 sharedstatedir='${prefix}/com'
 localstatedir='${prefix}/var'
+runstatedir='${localstatedir}/run'
 includedir='${prefix}/include'
 oldincludedir='/usr/include'
 docdir='${datarootdir}/doc/${PACKAGE_TARNAME}'
@@ -1132,6 +1134,15 @@
   | -silent | --silent | --silen | --sile | --sil)
     silent=yes ;;
 
+  -runstatedir | --runstatedir | --runstatedi | --runstated \
+  | --runstate | --runstat | --runsta | --runst | --runs \
+  | --run | --ru | --r)
+    ac_prev=runstatedir ;;
+  -runstatedir=* | --runstatedir=* | --runstatedi=* | --runstated=* \
+  | --runstate=* | --runstat=* | --runsta=* | --runst=* | --runs=* \
+  | --run=* | --ru=* | --r=*)
+    runstatedir=$ac_optarg ;;
+
   -sbindir | --sbindir | --sbindi | --sbind | --sbin | --sbi | --sb)
     ac_prev=sbindir ;;
   -sbindir=* | --sbindir=* | --sbindi=* | --sbind=* | --sbin=* \
@@ -1269,7 +1280,7 @@
 for ac_var in	exec_prefix prefix bindir sbindir libexecdir datarootdir \
 		datadir sysconfdir sharedstatedir localstatedir includedir \
 		oldincludedir docdir infodir htmldir dvidir pdfdir psdir \
-		libdir localedir mandir
+		libdir localedir mandir runstatedir
 do
   eval ac_val=\$$ac_var
   # Remove trailing slashes.
@@ -1422,6 +1433,7 @@
   --sysconfdir=DIR        read-only single-machine data [PREFIX/etc]
   --sharedstatedir=DIR    modifiable architecture-independent data [PREFIX/com]
   --localstatedir=DIR     modifiable single-machine data [PREFIX/var]
+  --runstatedir=DIR       modifiable per-process data [LOCALSTATEDIR/run]
   --libdir=DIR            object code libraries [EPREFIX/lib]
   --includedir=DIR        C header files [PREFIX/include]
   --oldincludedir=DIR     C header files for non-gcc [/usr/include]
@@ -10593,7 +10605,7 @@
  gai_strerror getgroups getlogin getloadavg getpeername getpgid getpid \
  getentropy \
  getpriority getresuid getresgid getpwent getspnam getspent getsid getwd \
- initgroups kill killpg lchmod lchown lstat mkfifo mknod mktime mmap \
+ initgroups kill killpg lchown lstat mkfifo mknod mktime mmap \
  mremap nice pathconf pause plock poll pthread_init \
  putenv readlink realpath \
  select sem_open sem_timedwait sem_getvalue sem_unlink setegid seteuid \
@@ -10616,6 +10628,17 @@
 done
 
 
+# Force lchmod off for Linux. Linux disallows changing the mode of symbolic
+# links. Some libc implementations have a stub lchmod implementation that always
+# returns an error.
+if test "$MACHDEP" != linux; then
+  ac_fn_c_check_func "$LINENO" "lchmod" "ac_cv_func_lchmod"
+if test "x$ac_cv_func_lchmod" = xyes; then :
+
+fi
+
+fi
+
 # For some functions, having a definition is not sufficient, since
 # we want to take their address.
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking for chroot" >&5