Use XORG_CHANGELOG to generate the changelog.

Steal the XORG_CHANGELOG macro from X.Org and stash it in acinclude.m4.

Makefile.am

@@ -8,6 +8,6 @@ EXTRA_DIST = vdpau.pc.in autogen.sh ChangeLog
 .PHONY: ChangeLog
 
 ChangeLog:
-	(GIT_DIR=$(top_srcdir)/.git git-log > .changelog.tmp && mv .changelog.tmp ChangeLog; rm -f .changelog.tmp) || (touch ChangeLog; echo 'git directory not found: installing possibly empty changelog.' >&2)
+	$(CHANGELOG_CMD)
 
 dist-hook: ChangeLog

acinclude.m4

+# XORG_CHANGELOG()
+# ----------------
+# Minimum version: 1.2.0
+#
+# Defines the variable CHANGELOG_CMD as the command to generate
+# ChangeLog from git.
+#
+# Arrange that distcleancheck ignores ChangeLog left over by distclean.
+#
+# Stolen from xorg-macros.m4, which has this license:
+# xorg-macros.m4.  Generated from xorg-macros.m4.in xorgversion.m4 by configure.
+#
+# Copyright 2005-2006 Sun Microsystems, Inc.  All rights reserved.
+#
+# Permission is hereby granted, free of charge, to any person obtaining a
+# copy of this software and associated documentation files (the
+# "Software"), to deal in the Software without restriction, including
+# without limitation the rights to use, copy, modify, merge, publish,
+# distribute, and/or sell copies of the Software, and to permit persons
+# to whom the Software is furnished to do so, provided that the above
+# copyright notice(s) and this permission notice appear in all copies of
+# the Software and that both the above copyright notice(s) and this
+# permission notice appear in supporting documentation.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+# OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT
+# OF THIRD PARTY RIGHTS. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
+# HOLDERS INCLUDED IN THIS NOTICE BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL
+# INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING
+# FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
+# NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
+# WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+#
+# Except as contained in this notice, the name of a copyright holder
+# shall not be used in advertising or otherwise to promote the sale, use
+# or other dealings in this Software without prior written authorization
+# of the copyright holder.
+#
+AC_DEFUN([XORG_CHANGELOG], [
+CHANGELOG_CMD="(GIT_DIR=\$(top_srcdir)/.git git log > .changelog.tmp && \
+mv .changelog.tmp ChangeLog) || (rm -f .changelog.tmp; touch ChangeLog; \
+echo 'git directory not found: installing possibly empty changelog.' >&2)"
+AC_SUBST([CHANGELOG_CMD])
+AC_SUBST([distcleancheck_listfiles], ['find . -type f ! -name ChangeLog -print'])
+]) # XORG_CHANGELOG

configure.ac

@@ -26,6 +26,8 @@ AC_CHECK_FUNC([dlopen], [],
         AC_CHECK_LIB([dl], [dlopen], DLOPEN_LIBS="-ldl"))
 AC_SUBST([DLOPEN_LIBS])
 
+XORG_CHANGELOG
+
 AC_OUTPUT([Makefile
            src/Makefile
            trace/Makefile