Fix for random failures in warnopts.test

[Pavel Roskin]

Hello!

warnopts.test fails randomly for me.  I have just applied this patch 
that fixes the problem:

        * tests/warnopts.test: Fix random failures by removing Autoconf
        cache directory when configure.in changes.  Use the code and the
        comment from tests/asm.test.

========================================================
--- tests/warnopts.test
+++ tests/warnopts.test
@@ -61,6 +61,14 @@
 # Only two lines of warnings.
 test `wc -l < stderr` = 2
 
+# On fast machines the autom4te.cache created during the above run of
+# $AUTOMAKE is likely to have the same time stamp as the configure.in
+# created below; thus causing traces for the old configure.in to be
+# used.  We could do `sleep 2', but it's faster to erase the
+# directory.  (Erase autom4te*.cache, not autom4te.cache, because some
+# bogus installations of Autoconf use a versioned cache.)
+rm -rf autom4te*.cache
+
 # If we add a global -Wnone, all warnings should disappear.
 cat >configure.in <<END
 AC_INIT([warnopts], [1.0])
===================================================

-- 
Regards,
Pavel Roskin