diff --git a/configure b/configure
index d1f21b8a08529c..ec4b7febdb4e2f 100755
--- a/configure
+++ b/configure
@@ -819,6 +819,8 @@ DFLAGS
 DTRACE
 GDBM_LIBS
 GDBM_CFLAGS
+X11_LIBS
+X11_CFLAGS
 TCLTK_LIBS
 TCLTK_CFLAGS
 LIBSQLITE3_LIBS
@@ -1075,6 +1077,8 @@ LIBSQLITE3_CFLAGS
 LIBSQLITE3_LIBS
 TCLTK_CFLAGS
 TCLTK_LIBS
+X11_CFLAGS
+X11_LIBS
 GDBM_CFLAGS
 GDBM_LIBS
 ZLIB_CFLAGS
@@ -1875,6 +1879,8 @@ Some influential environment variables:
   TCLTK_CFLAGS
               C compiler flags for TCLTK, overriding pkg-config
   TCLTK_LIBS  linker flags for TCLTK, overriding pkg-config
+  X11_CFLAGS  C compiler flags for X11, overriding pkg-config
+  X11_LIBS    linker flags for X11, overriding pkg-config
   GDBM_CFLAGS C compiler flags for gdbm
   GDBM_LIBS   additional linker flags for gdbm
   ZLIB_CFLAGS C compiler flags for ZLIB, overriding pkg-config
@@ -12365,6 +12371,109 @@ if test "x$found_tcltk" = xno; then :
 
 fi
 
+case $ac_sys_system in #(
+  FreeBSD*) :
+
+
+pkg_failed=no
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for X11" >&5
+$as_echo_n "checking for X11... " >&6; }
+
+if test -n "$X11_CFLAGS"; then
+    pkg_cv_X11_CFLAGS="$X11_CFLAGS"
+ elif test -n "$PKG_CONFIG"; then
+    if test -n "$PKG_CONFIG" && \
+    { { $as_echo "$as_me:${as_lineno-$LINENO}: \$PKG_CONFIG --exists --print-errors \"x11\""; } >&5
+  ($PKG_CONFIG --exists --print-errors "x11") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }; then
+  pkg_cv_X11_CFLAGS=`$PKG_CONFIG --cflags "x11" 2>/dev/null`
+		      test "x$?" != "x0" && pkg_failed=yes
+else
+  pkg_failed=yes
+fi
+ else
+    pkg_failed=untried
+fi
+if test -n "$X11_LIBS"; then
+    pkg_cv_X11_LIBS="$X11_LIBS"
+ elif test -n "$PKG_CONFIG"; then
+    if test -n "$PKG_CONFIG" && \
+    { { $as_echo "$as_me:${as_lineno-$LINENO}: \$PKG_CONFIG --exists --print-errors \"x11\""; } >&5
+  ($PKG_CONFIG --exists --print-errors "x11") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }; then
+  pkg_cv_X11_LIBS=`$PKG_CONFIG --libs "x11" 2>/dev/null`
+		      test "x$?" != "x0" && pkg_failed=yes
+else
+  pkg_failed=yes
+fi
+ else
+    pkg_failed=untried
+fi
+
+
+
+if test $pkg_failed = yes; then
+   	{ $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
+$as_echo "no" >&6; }
+
+if $PKG_CONFIG --atleast-pkgconfig-version 0.20; then
+        _pkg_short_errors_supported=yes
+else
+        _pkg_short_errors_supported=no
+fi
+        if test $_pkg_short_errors_supported = yes; then
+	        X11_PKG_ERRORS=`$PKG_CONFIG --short-errors --print-errors --cflags --libs "x11" 2>&1`
+        else
+	        X11_PKG_ERRORS=`$PKG_CONFIG --print-errors --cflags --libs "x11" 2>&1`
+        fi
+	# Put the nasty error message in config.log where it belongs
+	echo "$X11_PKG_ERRORS" >&5
+
+	as_fn_error $? "Package requirements (x11) were not met:
+
+$X11_PKG_ERRORS
+
+Consider adjusting the PKG_CONFIG_PATH environment variable if you
+installed software in a non-standard prefix.
+
+Alternatively, you may set the environment variables X11_CFLAGS
+and X11_LIBS to avoid the need to call pkg-config.
+See the pkg-config man page for more details." "$LINENO" 5
+elif test $pkg_failed = untried; then
+     	{ $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
+$as_echo "no" >&6; }
+	{ { $as_echo "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
+$as_echo "$as_me: error: in \`$ac_pwd':" >&2;}
+as_fn_error $? "The pkg-config script could not be found or is too old.  Make sure it
+is in your PATH or set the PKG_CONFIG environment variable to the full
+path to pkg-config.
+
+Alternatively, you may set the environment variables X11_CFLAGS
+and X11_LIBS to avoid the need to call pkg-config.
+See the pkg-config man page for more details.
+
+To get pkg-config, see <http://pkg-config.freedesktop.org/>.
+See \`config.log' for more details" "$LINENO" 5; }
+else
+	X11_CFLAGS=$pkg_cv_X11_CFLAGS
+	X11_LIBS=$pkg_cv_X11_LIBS
+        { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+$as_echo "yes" >&6; }
+
+      TCLTK_CFLAGS="$TCLTK_CFLAGS $X11_CFLAGS"
+      TCLTK_LIBS="$TCLTK_LIBS $X11_LIBS"
+
+fi
+
+ ;; #(
+  *) :
+     ;;
+esac
+
 save_CFLAGS=$CFLAGS
 save_CPPFLAGS=$CPPFLAGS
 save_LDFLAGS=$LDFLAGS
diff --git a/configure.ac b/configure.ac
index 61be89645d30a8..e7d595b3b4907d 100644
--- a/configure.ac
+++ b/configure.ac
@@ -3519,6 +3519,16 @@ AS_VAR_IF([found_tcltk], [no], [
   TCLTK_LIBS=${TCLTK_LIBS-""}
 ])
 
+dnl FreeBSD has an X11 dependency which is not implicitly resolved.
+AS_CASE([$ac_sys_system],
+  [FreeBSD*], [
+    PKG_CHECK_MODULES([X11], [x11], [
+      TCLTK_CFLAGS="$TCLTK_CFLAGS $X11_CFLAGS"
+      TCLTK_LIBS="$TCLTK_LIBS $X11_LIBS"
+    ])
+  ]
+)
+
 WITH_SAVE_ENV([
   CPPFLAGS="$TCLTK_CFLAGS $CFLAGS"
   LIBS="$TCLTK_LIBS $LDFLAGS"