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-rw-r--r--gnulib-m4/00gnulib.m422
1 files changed, 19 insertions, 3 deletions
diff --git a/gnulib-m4/00gnulib.m4 b/gnulib-m4/00gnulib.m4
index 301469b3..c7103ed5 100644
--- a/gnulib-m4/00gnulib.m4
+++ b/gnulib-m4/00gnulib.m4
@@ -1,12 +1,28 @@
-# 00gnulib.m4 serial 2
-dnl Copyright (C) 2009-2010 Free Software Foundation, Inc.
+# 00gnulib.m4 serial 3
+dnl Copyright (C) 2009-2015 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
dnl with or without modifications, as long as this notice is preserved.
dnl This file must be named something that sorts before all other
dnl gnulib-provided .m4 files. It is needed until such time as we can
-dnl assume Autoconf 2.64, with its improved AC_DEFUN_ONCE semantics.
+dnl assume Autoconf 2.64, with its improved AC_DEFUN_ONCE and
+dnl m4_divert semantics.
+
+# Until autoconf 2.63, handling of the diversion stack required m4_init
+# to be called first; but this does not happen with aclocal. Wrapping
+# the entire execution in another layer of the diversion stack fixes this.
+# Worse, prior to autoconf 2.62, m4_wrap depended on the underlying m4
+# for whether it was FIFO or LIFO; in order to properly balance with
+# m4_init, we need to undo our push just before anything wrapped within
+# the m4_init body. The way to ensure this is to wrap both sides of
+# m4_init with a one-shot macro that does the pop at the right time.
+m4_ifndef([_m4_divert_diversion],
+[m4_divert_push([KILL])
+m4_define([gl_divert_fixup], [m4_divert_pop()m4_define([$0])])
+m4_define([m4_init],
+ [gl_divert_fixup()]m4_defn([m4_init])[gl_divert_fixup()])])
+
# AC_DEFUN_ONCE([NAME], VALUE)
# ----------------------------