>From 40d297de7502f93a546126ff69d3f687f3d3ca1a Mon Sep 17 00:00:00 2001
From: Pavel Raiskup <address@hidden>
Date: Fri, 18 Sep 2015 23:17:07 +0200
Subject: [PATCH] libtoolize: fix infinite recursion in m4

Some projects use this construct in configure.ac:

  m4_define([version], m4_include([version])
  pkg_version=version

When the m4_include builtin is undefined (as is done in libtoolize
and extract-trace scripts), the call to 'version' macro goes to
infinite recursion (until ENOMEM).  Due to theirs usual
semantics/evaluation, other undefined macros/builtins should not
cause troubles here.

References:
http://lists.gnu.org/archive/html/libtool/2015-09/msg00000.html

* gl/build-aux/extract-trace (_G_mini): Redefine m4_include to
empty string rather than undefine it completely.
* NEWS: Document.
* NO-THANKS: Mention Hiroyuki Sato.
---
 NEWS                       | 4 ++++
 NO-THANKS                  | 1 +
 gl/build-aux/extract-trace | 5 ++++-
 3 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/NEWS b/NEWS
index c5c9023..e68c38c 100644
--- a/NEWS
+++ b/NEWS
@@ -2,6 +2,10 @@ NEWS - list of user-visible changes between releases of GNU Libtool
 
 * Noteworthy changes in release ?.? (????-??-??) [?]
 
+** Bug fixes:
+
+  - Fix significant slowdown of libtoolize for certain projects (regression
+    introduced in 2.4.3 release).
 
 * Noteworthy changes in release 2.4.6 (2015-02-15) [stable]
 
diff --git a/NO-THANKS b/NO-THANKS
index 10de16b..51ec8eb 100644
--- a/NO-THANKS
+++ b/NO-THANKS
@@ -82,6 +82,7 @@ Donn Washburn			address@hidden
 Erik van Pienbroek		address@hidden
 Ethan Mallove			address@hidden
 Fred Cox			address@hidden
+Hiroyuki Sato			address@hidden
 Jakub Bogusz			address@hidden
 James Su			address@hidden
 Jay Krell			address@hidden
diff --git a/gl/build-aux/extract-trace b/gl/build-aux/extract-trace
index 315a32a..ebbf42a 100755
--- a/gl/build-aux/extract-trace
+++ b/gl/build-aux/extract-trace
@@ -336,10 +336,13 @@ func_extract_trace ()
 
         # Disable these macros.
         m4_undefine([m4_dnl])
-        m4_undefine([m4_include])
         m4_undefine([m4_m4exit])
         m4_undefine([m4_m4wrap])
         m4_undefine([m4_maketemp])
+        # Rather do not use undefine here because people tend to define
+        # macros of the same name as file included in their bodies - which
+        # results in infinite recursion.
+        m4_define([m4_include], [])
 
         # Copy and rename macros not handled by "m4 --prefix".
         m4_define([dnl],         [m4_builtin([dnl])])
-- 
2.1.0