Merge branch 'fix-pr10470' into maint

* fix-pr10470:
  dist: avoid $(distdir) removal failure on MSYS/MinGW
  coverage: expose automake bug#10470 (distcheck-related)

3 files changed, 74 insertions, 5 deletions

diff --git a/lib/am/distdir.am b/lib/am/distdir.am
index a681101e0..cd2e4bf5f 100644
--- a/lib/am/distdir.am
+++ b/lib/am/distdir.am
@@ -1,6 +1,6 @@
 ## automake - create Makefile.in from Makefile.am
 ## Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009,
-## 2010, 2011 Free Software Foundation, Inc.
+## 2010, 2011, 2012 Free Software Foundation, Inc.
 
 ## This program is free software; you can redistribute it and/or modify
 ## it under the terms of the GNU General Public License as published by
@@ -23,10 +23,17 @@ distdir = $(PACKAGE)-$(VERSION)
 top_distdir = $(distdir)
 
 am__remove_distdir = \
-  { test ! -d "$(distdir)" \
-    || { find "$(distdir)" -type d ! -perm -200 -exec chmod u+w {} ';' \
-         && rm -fr "$(distdir)"; }; }
-
+  if test -d "$(distdir)"; then \
+    find "$(distdir)" -type d ! -perm -200 -exec chmod u+w {} ';' \
+      && rm -rf "$(distdir)" \
+## On MSYS (1.0.17) it is not possible to remove a directory that is in
+## use; so, if the first rm fails, we sleep some seconds and retry, to
+## give pending processes some time to exit and "release" the directory
+## before we remove it.  The value of "some seconds" is 5 for the moment,
+## which is mostly an arbitrary value, but seems high enough in practice.
+## See automake bug#10470.
+      || { sleep 5 && rm -rf "$(distdir)"; }; \
+  else :; fi
 endif %?TOPDIR_P%
 
 if %?SUBDIRS%
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 8817b64f8..e79c3beb4 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -352,6 +352,7 @@ distcheck-hook2.test \
 distcheck-missing-m4.test \
 distcheck-outdated-m4.test \
 distcheck-pr9579.test \
+distcheck-pr10470.test \
 distcheck-override-infodir.test \
 dmalloc.test \
 doc-parsing-buglets-colneq-subst.test \
diff --git a/tests/distcheck-pr10470.test b/tests/distcheck-pr10470.test
new file mode 100755
index 000000000..e774dd70d
--- /dev/null
+++ b/tests/distcheck-pr10470.test
@@ -0,0 +1,61 @@
+#! /bin/sh
+# Copyright (C) 2012 Free Software Foundation, Inc.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2, or (at your option)
+# any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+# Ensure "make distcheck" does not experience racy failures on
+# systems (like MinGW/MSYS) that cannot remove a directory "in use"
+# by a process (e.g., that is its "current working directory").
+# See automake bug#10470.
+
+parallel_tests=no
+. ./defs || Exit 1
+
+set -e
+
+mkdir foo.d
+sh -c "cd foo.d && sleep '4'" &
+# Without this sleep, the "rm -rf foo.d" below would reliably beat
+# the "cd foo.d" in the subshell above, and the test would be always
+# skipped, even on MinGW/MSYS.
+sleep '1'
+rm -rf foo.d && skip_ 'system is able to remove "in use" directories'
+
+echo AC_OUTPUT >> configure.in
+
+cat > Makefile.am <<END
+TESTS = foo.test
+EXTRA_DIST= foo.test
+END
+
+cat > foo.test <<END
+#!/bin/sh
+sleep '4' &
+exit 0
+END
+chmod a+x foo.test
+
+$ACLOCAL
+$AUTOCONF
+$AUTOMAKE
+./configure
+
+# We can build the distribution.
+$MAKE distcheck >output 2>&1 || { cat output; Exit 1; }
+cat output
+# Sanity check: verify that our code has hit a problem removing
+# the distdir, but has recovered from it.
+grep "rm:.*$destdir" output || fatal_ "expected code path not covered"
+
+: