[PATCH] m4: Update invocation of AC_PROG_LEX

[Łukasz Stelmach]

Commit 73f1be5e42e3 to autoconf has introduced an argument
to AC_PROG_LEX. Invocation without the argument has been treated
as obsolete since then.

* m4/lex.m4: pass the required argument to AC_PROG_LEX

* NEWS: Mention it
---
 NEWS      | 2 ++
 m4/lex.m4 | 6 +++---
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/NEWS b/NEWS
index ced0fd640..78162b746 100644
--- a/NEWS
+++ b/NEWS
@@ -57,6 +57,8 @@ New in 1.17:
 
   - tests: avoid some declaration conflicts for lex et al. on SunOS.
 
+  - Pass options AC_PROG_LEX requires
+
 * Obsolescent features:
 
   - py-compile no longer supports Python 0.x or 1.x versions.  Python 2.0,
diff --git a/m4/lex.m4 b/m4/lex.m4
index 7b0511526..9c7e036a9 100644
--- a/m4/lex.m4
+++ b/m4/lex.m4
@@ -6,14 +6,14 @@
 # gives unlimited permission to copy and/or distribute it,
 # with or without modifications, as long as this notice is preserved.
 
-# AM_PROG_LEX
-# -----------
+# AM_PROG_LEX(OPTIONS)
+# --------------------
 # Autoconf leaves LEX=: if lex or flex can't be found.  Change that to a
 # "missing" invocation, for better error output.
 AC_DEFUN([AM_PROG_LEX],
 [AC_PREREQ([2.50])dnl
 AC_REQUIRE([AM_MISSING_HAS_RUN])dnl
-AC_REQUIRE([AC_PROG_LEX])dnl
+AC_PROG_LEX([$1])dnl
 if test "$LEX" = :; then
   LEX=${am_missing_run}flex
 fi])
-- 
2.39.2